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Total mesorectal excision

Total mesorectal excision (TME) is a standardized surgical technique for treating rectal cancer, characterized by the complete en bloc removal of the rectum along with its surrounding mesorectum—the lymph node-bearing fatty tissue encased in an intact fascial envelope—to ensure clear circumferential margins and drastically reduce the risk of local tumor recurrence.^[1] This approach, which emphasizes sharp dissection in the avascular "holy plane" between the mesorectal and presacral fascias, has become the cornerstone of curative rectal cancer surgery worldwide.^[2] Pioneered by British surgeon Richard J. (Bill) Heald in the early 1980s, TME evolved from earlier anatomical insights into the mesorectum's role in cancer dissemination, building on observations by researchers like Quirke who highlighted the prognostic importance of circumferential resection margins.^[3] In a landmark 1982 publication, Heald first articulated the concept of total mesorectal excision as a radical operation to address pelvic recurrence, which historically affected up to 30-38% of patients treated with conventional rectal resections.^[1] A prospective series from 1986 further demonstrated TME's efficacy, reporting local recurrence rates below 4% and 5-year survival rates exceeding 80% in a cohort of 101 patients, marking a paradigm shift from prior techniques like Miles' abdominoperineal resection.^[4] While traditionally performed via open laparotomy, advancements have integrated minimally invasive methods, including laparoscopic and robotic-assisted TME, which yield comparable oncologic results—such as equivalent rates of complete mesorectal excision and negative margins—while reducing postoperative pain, hospital stays, and recovery time, as evidenced by multicenter trials like COLOR II and COREAN.^[3] For mid- and low-rectal tumors, transanal TME (taTME) has emerged as a hybrid technique to improve visualization and resection quality in narrow pelvises; international registry data show low conversion rates (around 8-11%) and favorable short-term outcomes in experienced centers, though safety concerns have arisen, including a 2018 Norwegian moratorium due to elevated local recurrence rates in some implementations, prompting calls for rigorous training and patient selection.^[3]^[5] As the gold standard for rectal cancer management, TME—often combined with neoadjuvant chemoradiotherapy for locally advanced disease—has transformed prognosis, lowering local recurrence to under 10% and enhancing overall and disease-free survival across stages, as confirmed by systematic reviews and meta-analyses of thousands of patients.^[6] Quality assessment of the mesorectal specimen, graded as complete, near-complete, or incomplete based on pathological evaluation, directly correlates with outcomes, underscoring the technique's emphasis on surgical precision.^[2] Ongoing innovations, such as artificial intelligence-guided navigation and novel robotic platforms, aim to further standardize TME and address challenges in complex anatomies, potentially extending benefits to more patients while maintaining low complication rates like anastomotic leaks (5-10%).^[3]

Background

Anatomy of the rectum and mesorectum

The rectum is the terminal portion of the large intestine, extending from the sigmoid colon at the level of the sacral promontory (approximately 15 cm from the anal verge) to the anorectal junction, where it transitions into the anal canal. It measures about 12-15 cm in length and follows the anterior concavity of the sacrum and coccyx, forming an S-shaped curve. The upper third (approximately 10-15 cm from the anal verge) is intraperitoneal, covered by peritoneum on its anterior and lateral surfaces, while the middle third (6-10 cm) is partially intraperitoneal anteriorly and the lower third (≤5 cm) is entirely extraperitoneal, lacking peritoneal coverage.^[7]^[8] The arterial blood supply to the rectum arises from three main sources: the superior rectal artery, a direct continuation of the inferior mesenteric artery, which supplies the upper two-thirds; the middle rectal arteries, branches from the internal iliac artery that are present in 12-57% of individuals and supply the lower rectum; and the inferior rectal arteries, originating from the internal pudendal artery to vascularize the distal rectum and anal canal. Venous drainage parallels the arterial supply, with the superior rectal vein draining into the portal system via the inferior mesenteric vein, while the middle and inferior rectal veins contribute to the systemic circulation through the internal iliac and internal pudendal veins, respectively. Lymphatic drainage primarily follows the superior rectal artery to mesorectal and inferior mesenteric nodes, with lateral pathways along the middle rectal arteries to internal iliac and obturator nodes; the mesorectum typically contains 14-28 lymph nodes.^[7]^[9]^[10] The mesorectum is a fatty mesentery-like envelope that surrounds the rectum, containing lymph nodes, autonomic nerves, blood vessels, and lymphatic channels essential for its function. It forms a conical structure that is thickest posteriorly and laterally in the mid-rectum, bilobed posteriorly, and tapers distally toward the anorectal junction, becoming nearly absent about 2 cm above the puborectalis muscle. The mesorectum is encased by the fascia propria of the rectum (also known as the mesorectal fascia), a thin layer continuous with the peritoneal covering proximally; anteriorly, it is bounded by Denonvilliers' fascia, which separates the rectum from prostate/seminal vesicles in males or vagina/cervix in females; and posteriorly by the presacral fascia, which covers the sacrum and coccyx, fusing with the mesorectal fascia at S4 via the rectosacral ligament. Cross-sectional views, such as those obtained via MRI in axial, sagittal, and coronal planes, illustrate these boundaries clearly, highlighting the mesorectal fascia as a hypointense line surrounding the mesorectal fat.^[7]^[9]^[8] The "holy plane" refers to the avascular areolar tissue plane between the mesorectal fascia and the surrounding parietal pelvic fascia (including the presacral fascia posteriorly), which allows for complete excision of the rectum and its mesorectum while preserving adjacent structures. This plane's loose connective tissue minimizes vascular and neural disruption during dissection. The mesorectum's lymphatic pathways play a key role in the potential spread of rectal cancer.^[7]^[8]^[10]

Rectal cancer overview

Rectal cancer, a subtype of colorectal cancer, represents a significant global health burden, with an estimated 729,833 new cases diagnosed worldwide in 2022, ranking as the eighth most common cancer overall.^[11] Incidence rates are highest in developed regions such as Europe and Northern America, with age-standardized rates reaching up to 25.9 per 100,000 in males in some areas.^[11] The disease predominantly affects older adults, with over 90% of cases occurring in individuals aged 50 years or older, and exhibits a slight male predominance, with global rates approximately 1.5 times higher in men than women.^[12] Key risk factors include advanced age, diets low in fiber and fruits/vegetables but high in processed meats and red meat, obesity, smoking, excessive alcohol consumption, and genetic predispositions such as Lynch syndrome or familial adenomatous polyposis.^[12] Pathologically, the vast majority of rectal cancers—over 95%—are adenocarcinomas arising from glandular epithelial cells, often progressing from precancerous adenomas via the adenoma-carcinoma sequence.^[13] These tumors typically spread locally by direct extension through the rectal wall and via lymphatic channels within the mesorectum, which contains the primary regional lymph nodes; this pattern underscores the importance of complete lymphatic clearance in managing the disease.^[13] Staging employs the TNM system of the American Joint Committee on Cancer (AJCC), where T classification reflects tumor depth (T1: submucosa; T2: muscularis propria; T3: perirectal tissues; T4: adjacent organs or peritoneum), N indicates nodal involvement (N0: none; N1: 1-3 regional nodes; N2: 4 or more), and M denotes distant metastasis (M0: absent; M1: present).^[14] Early-stage tumors (T1-2, N0) have favorable prognoses, while advanced stages (T3-4 or N+) correlate with higher risks of recurrence and metastasis.^[14] Patients often present with symptoms such as rectal bleeding (hematochezia), changes in bowel habits including diarrhea or constipation, a sensation of incomplete evacuation, abdominal pain, or, in advanced low rectal tumors, bowel obstruction.^[13] Diagnosis begins with colonoscopy for visualization and biopsy confirmation, followed by magnetic resonance imaging (MRI) of the pelvis for precise local staging, particularly to assess tumor depth and nodal status, while computed tomography (CT) scans evaluate for distant metastases.^[13] Endorectal ultrasound may supplement MRI for early-stage tumors.^[13] Prognostic factors include tumor location within the rectum—low rectal tumors (within 5 cm of the anal verge) pose greater challenges due to anatomical constraints and higher likelihood of margin involvement, compared to mid (5-10 cm) or high (10-15 cm) lesions—and the circumferential resection margin (CRM), defined as the radial distance from the deepest tumor invasion to the mesorectal fascia.^[15] A CRM of 1 mm or less is associated with increased local recurrence rates (up to 10-20% higher) and poorer overall survival, serving as a critical predictor independent of TNM stage.^[16] Other influencers include histologic grade, lymphovascular invasion, and perineural invasion, with poorly differentiated tumors indicating worse outcomes.^[13]

History

Development and key pioneers

Prior to the development of total mesorectal excision (TME), rectal cancer surgery typically involved blunt dissection of the rectum, which often left residual mesorectal tissue containing microscopic tumor deposits, resulting in high local recurrence rates of 15-45%.^[17] This approach failed to address the lateral spread of tumor cells beyond the rectal wall, contributing to poor oncologic outcomes and emphasizing the need for more precise excision techniques.^[18] The foundational work on lymphatic spread in rectal cancer, conducted by Russell S. Grinnell in the 1950s, provided critical anatomical insights that later informed TME. Grinnell's studies demonstrated the extensive radial lymphatic drainage within the mesorectum, highlighting the importance of en bloc resection to capture potential metastatic sites and reduce local failure.^[19] These findings underscored the limitations of conventional surgery and set the stage for targeted improvements in the 1980s. TME was pioneered by British surgeon Richard J. (Bill) Heald, who introduced the technique in 1982 at Basingstoke District Hospital in the United Kingdom, advocating for sharp dissection along the mesorectal fascia to achieve complete removal of the mesorectum.^[1] Heald's first formal description appeared in a 1986 publication, where he detailed the procedure's emphasis on preserving autonomic nerves while ensuring oncologic clearance.^[4] Concurrently, pathologist Philip Quirke's histopathological analyses in the mid-1980s revealed that local recurrences were primarily due to inadequate lateral margins from non-anatomic dissections, further validating the need for TME through meticulous pathological assessment of resection specimens.^[20] Initial evidence from Heald's prospective series at Basingstoke demonstrated the efficacy of TME, with local recurrence rates dropping to less than 5% in patients undergoing curative resections by the late 1980s, a marked improvement over prior standards.^[4] This early success, based on over 50 cases with minimal pelvic failures, established TME as a transformative approach grounded in anatomical precision.^[21]

Adoption and global standardization

Following the initial description of total mesorectal excision (TME) by Richard Heald in the early 1980s, its adoption accelerated in Europe through structured teaching programs and workshops led by Heald at the Basingstoke clinic, which trained surgeons from across the continent and emphasized meticulous sharp dissection to achieve optimal oncologic outcomes.^[3] This dissemination was bolstered by seminal clinical trials in the 1990s and 2000s that provided high-level evidence for TME's efficacy when combined with adjuvant therapies. The Dutch TME trial, a multicenter randomized study initiated in 1996 by the Dutch Colorectal Cancer Group, enrolled over 1,800 patients with resectable rectal cancer and compared preoperative short-course radiotherapy followed by TME against TME alone, demonstrating a significant reduction in local recurrence rates (2.4% versus 8.2% at 2 years) without compromising overall survival.^[17] Long-term follow-up from this trial confirmed sustained benefits, with 5-year local recurrence rates of 5.6% in the radiotherapy arm compared to 11.4% in the surgery-only group.^[22] Building on these findings, the UK-based MRC CR07 trial, launched in the early 2000s and reported in 2009, further refined TME's role by randomizing 1,355 patients to either preoperative short-course radiotherapy or selective postoperative chemoradiotherapy based on pathological risk factors, both paired with TME surgery.^[23] The trial established that preoperative radiotherapy achieved superior local control (local recurrence of 14.7% versus 4.4% at 3 years), influencing the shift toward routine preoperative strategies in operable rectal cancer while highlighting TME's foundational importance in minimizing recurrence regardless of timing.^[23] These trials collectively drove widespread European implementation, with TME becoming the standard surgical approach by the mid-1990s through national audits and quality improvement programs that audited surgical plane achievement and recurrence patterns.^[24] In the United States, TME integration occurred more gradually but was formalized by the early 2000s through updates to the National Comprehensive Cancer Network (NCCN) guidelines for rectal cancer, which by 2000 explicitly recommended TME as the optimal technique for mid- and low-rectal tumors to ensure complete mesorectal removal and reduce local failure.^[25] This alignment with European evidence facilitated broader adoption, supported by multidisciplinary training initiatives; in the UK, programs such as the national training initiative for advanced rectal procedures emphasized proctored cases and competency assessment to standardize TME execution.^[26] Standardization efforts extended to pathological evaluation, pioneered by Philip Quirke's work on circumferential resection margin (CRM) assessment, which since the 1990s has served as a key quality metric for TME specimens—CRM involvement predicts higher local recurrence (up to 25% in involved cases versus <5% in clear margins)—prompting routine macroscopic and microscopic auditing in surgical pathology.^[27] By the 2000s, international guidelines solidified TME's status: the European Society for Medical Oncology (ESMO) endorsed it as the gold standard for rectal cancer surgery in its 2003 minimum clinical recommendations, strongly recommending total mesorectal excision [II, A evidence level], while the American Society of Clinical Oncology (ASCO) similarly incorporated TME into recommendations for early-stage and locally advanced disease by the mid-2000s.^[28] These endorsements, coupled with global training and audit systems, marked key milestones in TME's dissemination, culminating in a dramatic decline in local recurrence rates from approximately 25-30% in the pre-TME era (1970s-1980s conventional surgery) to 5-10% worldwide by 2010, even in unselected populations undergoing TME with or without radiotherapy.^[29]^[30] This improvement underscored TME's transformative impact on rectal cancer outcomes, shifting focus from palliation to curative intent on a global scale.

Indications and preparation

Patient selection criteria

Total mesorectal excision (TME) is primarily indicated for patients with mid- to low-rectal cancers, typically those located within 10 cm from the anal verge, where complete removal of the mesorectum is essential to minimize local recurrence.^[31] For upper rectal tumors (beyond 10-15 cm from the anal verge), partial mesorectal excision is often sufficient instead of full TME, as the lymphatic drainage is primarily upward toward the sigmoid mesocolon.^[32] Tumor staging plays a critical role in selection; TME is recommended for clinical stages T2-T3 N0-N1 without high-risk features, while high-risk locally advanced disease (e.g., cT4, N2, extramural vascular invasion, or threatened circumferential resection margin) typically requires neoadjuvant therapy prior to TME for downstaging.^[31] Early-stage tumors (cT1N0) without adverse features such as poor differentiation or lymphovascular invasion may be suitable for local excision rather than TME to preserve sphincter function and avoid major surgery. Patient-specific factors significantly influence suitability for TME, particularly in assessing operative risk and potential for sphincter preservation. Comorbidities, such as severe cardiopulmonary disease or high American Society of Anesthesiologists (ASA) scores (≥4), represent relative contraindications, as they increase perioperative morbidity and mortality; in such cases, less invasive options like local excision or non-operative management may be considered after multidisciplinary evaluation.^[33] For elderly patients (>70 years), comprehensive geriatric assessment is advised to evaluate frailty, nutritional status, and functional reserve, as these can predict postoperative complications and guide toward tailored approaches.^[31] Sphincter preservation feasibility is a key consideration for low rectal tumors (<5 cm from anal verge), depending on tumor location, size, and response to neoadjuvant therapy, with abdominoperineal resection incorporating TME reserved when low anterior resection is not possible without compromising margins or function. Absolute contraindications to curative-intent TME include distant metastases (M1 disease) or unresectable local invasion, such as direct extension to the sacrum, pelvic sidewall, or prostate in males, where palliative approaches are prioritized over radical resection.^[34] Additionally, tumors with mismatch repair deficiency (dMMR)/microsatellite instability-high (MSI-H) status may warrant immunotherapy over upfront surgery in select advanced cases, altering the pathway to TME.^[31] Overall, selection emphasizes a multidisciplinary approach to balance oncologic efficacy with patient quality of life, ensuring TME is pursued only when it offers clear survival benefit without excessive risk.^[35]

Preoperative assessment and neoadjuvant therapy

Preoperative assessment for total mesorectal excision (TME) in rectal cancer involves a multidisciplinary team (MDT) review, including surgeons, medical and radiation oncologists, radiologists, and pathologists, to determine staging, resectability, and treatment planning.^[36] This evaluation ensures optimal patient selection and integration of neoadjuvant strategies to improve surgical outcomes.^[31] Staging relies on imaging modalities to assess tumor depth (T stage), nodal involvement (N stage), and circumferential resection margin (CRM) involvement, which predicts local recurrence risk. Endorectal ultrasound (EUS) is recommended for evaluating superficial or early-stage tumors (T1-T2), offering accuracy comparable to MRI for nodal assessment (sensitivity 67%, specificity 78%), though it is operator-dependent and less reliable for bulky or proximal lesions.^[36] Pelvic MRI is the preferred method for local staging, providing high-resolution assessment of T and N stages, extramural vascular invasion, and CRM (clear CRM >1 mm; threatened CRM ≤1 mm), guiding neoadjuvant decisions and TME feasibility.^[31]^[36] Positron emission tomography-computed tomography (PET-CT) is not routine but is used for equivocal findings on CT or to detect distant metastases in potentially curable cases, with sensitivity of 94% and specificity of 77% for elevated CEA levels.^[36] Chest/abdomen CT complements these for systemic staging.^[31] Neoadjuvant therapy is standard for locally advanced rectal cancer (T3-T4 or node-positive) to downstage tumors, enhance sphincter preservation, and reduce local recurrence prior to TME. Long-course chemoradiotherapy (CRT) delivers 45-50.4 Gy in 25-28 fractions over 5-6 weeks with concurrent fluoropyrimidine sensitization (5-fluorouracil at 225 mg/m²/day or capecitabine at 825 mg/m² twice daily), recommended for cases threatening CRM or requiring downstaging.^[36]^[31] Short-course radiotherapy (SCRT), at 25 Gy in 5 fractions over 5 days without chemotherapy, is an alternative for resectable T3N0 or T1-3N1-2 tumors, particularly when immediate surgery is feasible or in resource-limited settings, showing equivalent local control to long-course CRT without overall survival differences.^[36]^[31] Total neoadjuvant therapy (TNT), incorporating induction chemotherapy (e.g., FOLFOX or CAPOX for 12-16 weeks) before CRT or SCRT, is increasingly preferred for high-risk cases to boost pathologic complete response rates (up to 36%).^[36] Response to neoadjuvant therapy is evaluated 5-12 weeks post-CRT or 4-8 weeks post-SCRT using MRI, endoscopy, and digital rectal examination to identify clinical complete response (cCR), defined as no residual tumor on imaging or exam.^[36]^[31] For complete responders, a watch-and-wait strategy—active surveillance without immediate TME—has gained acceptance since the 2010s in experienced centers, offering rectal preservation with 5-year overall survival of 100% and disease-free survival of 92%, though it requires rigorous MDT-monitored follow-up due to regrowth risk (up to 25%).^[36]^[31] Surgery is typically scheduled 6-8 weeks post-therapy to allow maximal tumor regression while minimizing fibrosis.^[36] Patient optimization includes mechanical bowel preparation combined with oral antibiotics to reduce surgical site infections (from 16% to 7.2%), administered the day before surgery.^[37] Preoperative stoma site marking by an enterostomal therapist is standard for patients likely needing a temporary or permanent ostomy, assessing optimal abdominal sites in multiple positions to minimize complications and improve quality of life.^[38]^[39] Nutritional support targets malnourished patients (e.g., via oral supplements providing 1.2-1.5 g/kg/day protein for 1-2 weeks), as low prognostic nutritional index correlates with higher postoperative morbidity, ensuring better tolerance of therapy and surgery.^[37]00179-3/fulltext)

Surgical technique

Principles of mesorectal excision

Total mesorectal excision (TME) is grounded in the principle of sharp dissection along the holy plane, an avascular fascial plane between the visceral mesorectal fascia and the parietal endopelvic fascia, to remove the rectum and its surrounding mesorectum as an intact, envelope-covered unit. This approach, first articulated by Heald, minimizes disruption to the mesorectal fascia, thereby reducing the risk of tumor cell spillage and local recurrence by preserving the natural anatomical boundaries of the mesorectum.^[40] The holy plane dissection ensures complete mobilization of the mesorectum while avoiding entry into the mesorectal fat, which could compromise oncologic outcomes.^[40] The quality of the excised mesorectal specimen is evaluated using the Quirke classification, a standardized pathological grading system that assesses the integrity of the mesorectum based on its macroscopic appearance. Specimens are graded as complete (Grade 3) if the mesorectum is intact with smooth or only minor surface irregularities and no defects deeper than 5 mm; near-complete (Grade 2) if the mesorectum has a moderate but irregular surface with some coning and defects greater than 5 mm but without visible muscularis propria except at the levator insertion; or incomplete (Grade 1) if the mesorectum has a small bulk with very irregular surface, significant defects extending to the muscularis propria or beyond, and severe coning. This grading correlates directly with local recurrence rates, with complete excisions associated with the lowest risk.^[41] The primary goals of TME are to achieve a negative CRM, defined as at least 1 mm clearance between the tumor and the mesorectal fascia, and a distal resection margin of greater than 1 cm to ensure oncologic adequacy. TME refers to total excision of the entire mesorectum down to the pelvic floor for mid and low rectal tumors, whereas partial mesorectal excision (PME) involves removing only the portion of the mesorectum distal to the tumor for upper rectal cancers, preserving more proximal mesorectum to facilitate anastomosis.^[42] These margins aim for R0 resection status, indicating no microscopic residual tumor at any resection edge. Pathological examination of the TME specimen includes meticulous assessment for lymph node retrieval, with a minimum of 12 nodes recommended to accurately stage the disease and guide adjuvant therapy decisions, as fewer nodes may lead to understaging. The examination confirms R0 status by verifying negative proximal, distal, and circumferential margins, alongside evaluation of tumor penetration and lymphovascular invasion, which collectively inform prognosis and recurrence risk.^[43]

Open and minimally invasive approaches

Total mesorectal excision (TME) can be performed via an open approach, which involves a traditional midline laparotomy incision to access the abdominal cavity and mobilize the rectum from above. The procedure begins with exploration of the peritoneal cavity, followed by high ligation of the inferior mesenteric artery (IMA) at its origin to ensure adequate lymph node dissection and blood supply to the proximal colon. The inferior mesenteric vein (IMV) is then ligated, the splenic flexure is mobilized to facilitate tension-free anastomosis, and the descending or sigmoid colon is divided using a stapling device. Dissection proceeds in the mesorectal plane, encircling the rectum while preserving the autonomic nerves and achieving complete mesorectal excision. This approach allows direct visualization and palpation, particularly beneficial in cases with adhesions or bulky tumors, though it is associated with greater postoperative pain and longer recovery times compared to minimally invasive methods.^[3] Laparoscopic TME represents a minimally invasive alternative, utilizing 4-5 trocars for port placement, typically in a semicircular arrangement around the umbilicus, with establishment of pneumoperitoneum at 12-15 mmHg to create working space. The technique mirrors open TME in vascular ligation and mobilization but employs instruments like the harmonic scalpel or energy devices for dissection, starting medially at the IMA root and progressing to splenic flexure takedown. Advantages include reduced intraoperative blood loss (mean 203 mL) and lower rates of wound infections relative to open surgery, alongside shorter hospital stays and improved cosmesis. However, challenges arise in narrow male pelvises or after neoadjuvant therapy, leading to conversion rates of 10-20%, often due to technical difficulties in achieving the holy plane dissection. Seminal studies, such as the prospective series by Liang et al., demonstrated feasibility with a 12% conversion rate and comparable oncologic outcomes to open TME.^[44]^[45]^[46] Robotic-assisted TME further refines minimally invasive access, leveraging systems like the da Vinci platform for three-dimensional visualization, tremor filtration, and articulated instruments that enhance dexterity in the deep pelvis. Introduced in the early 2010s, it facilitates precise dissection in low rectal tumors, with docking of the robot after initial laparoscopic exploration and port placement similar to standard laparoscopy. Key benefits include lower conversion rates (1.4% versus 8.8% for laparoscopic TME) and higher rates of complete mesorectal excision, particularly in obese patients or those with a narrow pelvis. Evidence from multicenter trials, such as the REAL study, supports non-inferiority to laparoscopic TME in short-term outcomes, with advantages in circumferential resection margin negativity (4.0% positive rate versus 7.2%) and reduced complications. Operative times are longer due to setup, but adoption has grown for its ergonomic benefits to surgeons.^[47]^[48]^[49] Following mesorectal mobilization in any approach, restoration of bowel continuity typically involves a colorectal or coloanal anastomosis, depending on tumor location and rectal stump length. A stapled colorectal anastomosis joins the descending colon to the rectal remnant above the peritoneal reflection, while a hand-sewn coloanal anastomosis is used for very low tumors, often requiring partial or total mesorectal excision down to the levators. To mitigate anastomotic leakage rates (up to 10-15%), a temporary diverting loop ileostomy is routinely created, diverting fecal stream for 6-12 weeks until reversal, thereby reducing severe sepsis risk. This protective strategy is standard in low anterior resections, with evidence showing decreased clinical leak severity without impacting long-term oncologic results.^[50]^[51]

Transanal total mesorectal excision

Transanal total mesorectal excision (taTME) is a hybrid surgical technique developed to address limitations in accessing and resecting low-lying rectal tumors, first reported in 2010 by Sylla et al. as a natural orifice transluminal endoscopic surgery (NOTES)-inspired approach combining transanal endoscopic microsurgery with laparoscopic assistance. This method involves coordinated bottom-up dissection from the transanal approach meeting top-down mobilization from the abdominal side, enabling precise excision in anatomically challenging cases. Indications for taTME primarily include mid- and low rectal cancers, particularly distal tumors located less than 5 cm from the anal verge, where traditional abdominal approaches may be hindered by limited visibility, narrow pelvic anatomy, or obesity. It is especially suited for cases where achieving adequate distal margins and preserving sphincter function are critical, often in patients who would otherwise require abdominoperineal resection.^[52] The procedure begins with the patient in a modified Lloyd-Davis position, where a transanal access platform, such as the GelPoint Path or similar gel-sealed port, is inserted into the anus to establish pneumorectum via CO2 insufflation at low pressures (typically 8-12 mmHg) to maintain rectal distension without excessive billowing.^[53] A purse-string suture is placed proximal to the tumor to isolate the distal rectum, followed by circumferential dissection of the mesorectum using endoscopic instruments, starting from the distal end and proceeding proximally to meet the abdominal team's mobilization in a "meet-in-the-middle" fashion.^[54] The abdominal component typically involves laparoscopic or robotic assistance for vascular control and proximal dissection, with specimen extraction often transanally to minimize incisions.^[55] Key advantages of taTME include enhanced visualization of the distal mesorectum, allowing for more accurate determination of resection margins and reduced risk of inadvertent tumor perforation.^[56] This approach has been associated with higher rates of sphincter preservation, potentially avoiding permanent colostomy in up to 80-90% of suitable low rectal cancer cases, compared to traditional methods.^[57] Evidence from the COLOR III trial, a multicenter randomized comparison of taTME versus laparoscopic TME for mid- and low rectal cancer, supports improved short-term outcomes such as lower conversion rates and comparable specimen quality, with the 2025 report demonstrating noninferiority in 3-year disease-free survival (82.1% for taTME vs. 79.4% for laparoscopic TME) and local recurrence rates (3.6% vs. 4.4%).^[58] Technical considerations for taTME emphasize the use of rigid platforms, such as the transanal endoscopic microsurgery (TEM) proctoscope, for stable access in select cases, alongside flexible laparoscopic towers equipped with high-definition cameras for optimal depth perception.^[59] Dual insufflators—one for the abdomen and one for the rectum—help manage pressure gradients and prevent collapse during dissection.^[60] The procedure carries a steep learning curve, with proficiency typically achieved after 40-50 cases to optimize operative times, margin negativity, and complication rates, underscoring the need for supervised training in high-volume centers.^[61]

Intraoperative and postoperative management

Nerve preservation and surgical planes

The pelvic autonomic nervous system plays a critical role in preserving sexual and urinary functions during total mesorectal excision (TME) for rectal cancer. The superior hypogastric plexus, originating from the lumbar sympathetic chain (L1-L2), descends anterior to the sacral promontory and bifurcates into left and right hypogastric nerves, which provide sympathetic innervation primarily responsible for ejaculation and bladder neck closure. The pelvic splanchnic nerves (nervi erigentes), arising from S2-S4, deliver parasympathetic fibers that facilitate erection and bladder detrusor contraction. These structures course along the pelvic sidewalls and mesorectal fascia, making them vulnerable to iatrogenic injury during dissection.^[62] Preservation of these nerves is integral to the TME with autonomic nerve preservation (TME-ANP) technique, which emphasizes meticulous identification and sharp dissection within the "holy plane"—the avascular mesofascial plane between the mesorectum and pelvic sidewall—to avoid lateral margins where nerves are adherent. Surgeons begin by exposing the superior hypogastric plexus at the sacral promontory, mobilizing the hypogastric nerves laterally while preserving their continuity to the inferior hypogastric plexuses at the pelvic floor. Pelvic splanchnic nerves are safeguarded during posterior and lateral mesorectal mobilization by maintaining a 5-mm margin from the rectal wall and using gentle traction to visualize nerve roots entering the plexuses. This approach, pioneered in the 1990s, integrates nerve-sparing principles into standard TME without compromising oncologic radicality.^[63] Certain risk factors heighten the challenge of nerve preservation, particularly in low rectal tumors requiring extended dissection near the pelvic floor, where anatomical distortion increases injury risk. Neoadjuvant chemoradiotherapy further complicates identification by inducing perineural fibrosis and inflammation, potentially obscuring nerve planes. Despite these efforts, postoperative dysfunction remains notable; with nerve preservation, sexual dysfunction rates are typically 10-35% and urinary dysfunction 0-30% in males, while rates can reach 40-50% without preservation.^[64]^[65] Intraoperative neuromonitoring has emerged since the 2010s as an adjunct to enhance nerve preservation, using bioimpedance or electromyographic signals to map and confirm integrity of the pelvic autonomic nerves in real time. This technology allows dynamic feedback during dissection, reducing inadvertent damage and improving functional outcomes, as demonstrated in prospective trials where neuromonitoring correlated with lower rates of anoneorectal dysfunction compared to standard TME. Recent advancements include artificial intelligence-assisted recognition systems for pelvic autonomic nerves, showing promise in further reducing dysfunction rates during laparoscopic TME.^[66]^[67]^[68]

Recovery protocols and complications

Recovery from total mesorectal excision (TME) often incorporates enhanced recovery after surgery (ERAS) protocols, which emphasize multimodal strategies to accelerate postoperative rehabilitation and reduce hospital length of stay.^[69] These protocols promote early mobilization, with patients encouraged to be out of bed for at least 2 hours on the day of surgery and 6 hours thereafter, alongside fluid and carbohydrate loading preoperatively to minimize catabolic effects. Pain management within ERAS focuses on opioid minimization through multimodal analgesia, including regional blocks, nonsteroidal anti-inflammatory drugs, and acetaminophen, which has been shown to decrease opioid requirements and associated side effects like ileus.^[70] For patients with a temporary diverting ileostomy, reversal is typically scheduled 8 to 12 weeks postoperatively, allowing time for anastomotic healing and adjuvant therapy completion while optimizing functional outcomes.^[71] Common complications following TME include anastomotic leak, occurring in 5% to 15% of cases, particularly with low rectal anastomoses, and is influenced by factors such as neoadjuvant radiation and surgical technique.^[72] Wound infections affect approximately 5% to 10% of patients, often managed conservatively with antibiotics but contributing to prolonged recovery in some instances.^[73] Stoma-related issues, such as high-output ileostomy, prolapse, parastomal hernia, and skin irritation, arise in over 50% of cases with temporary ileostomies and may necessitate readmission or revision.^[74] Sexual and urinary dysfunction, primarily due to autonomic nerve damage during pelvic dissection, manifests temporarily in up to 25% of patients for urinary issues and 10% to 35% for sexual dysfunction, though nerve-preserving techniques can mitigate long-term rates to under 5% for urinary problems.^[75] Management of complications begins with vigilant monitoring; anastomotic leaks are detected via computed tomography (CT) with rectal contrast, which enhances sensitivity for extraluminal fluid or air collections.^[76] Severe leaks or dehiscence often require reoperation in about 63% of cases, involving drainage, resection, or creation of a permanent stoma to control sepsis.^[77] Postoperative surveillance includes serial carcinoembryonic antigen (CEA) level measurements every 3 to 6 months initially, alongside colonoscopy at 1 year post-resection to evaluate for metachronous lesions or recurrence.^[78] Perioperative mortality remains low at under 2% to 3% in high-volume centers, reflecting improvements in surgical expertise and supportive care.^[79]

Outcomes and evidence

Survival and recurrence rates

Total mesorectal excision (TME) has significantly reduced local recurrence rates in rectal cancer compared to historical conventional surgery techniques. Prior to widespread adoption of TME, local recurrence rates after 3 years were approximately 30% with conventional methods, whereas TME achieved rates of 11% in comparative studies.^[80] In the landmark Dutch TME trial, 5-year local recurrence rates were 10.9% with TME alone and further decreased to 5.6% when combined with preoperative short-course radiotherapy, demonstrating TME's efficacy in enhancing local control.^[81] Overall, modern TME series report 5-year local recurrence rates of 3-8%, a marked improvement from the 20-30% seen historically without standardized mesorectal excision.^[80] For stages II and III rectal cancer, 5-year overall survival rates following TME typically range from 60% to 80%, with disease-free survival also benefiting from complete mesorectal excision.^[82] In the Dutch TME trial, 5-year overall survival was 63.5% with TME alone and 64.2% with added preoperative radiotherapy, reflecting no significant survival difference between arms but underscoring TME's role in stabilizing outcomes.^[81] Improvements in disease-free survival are particularly associated with high-quality TME, where complete excision minimizes residual disease risk.^[81] Key factors influencing these outcomes include circumferential resection margin (CRM) status and lymph node yield. A positive CRM, defined as tumor within 1 mm of the resection margin, is a strong independent predictor of poorer survival, distant metastasis, and local recurrence, often halving 5-year survival rates in affected patients compared to negative margins.^[83] Adequate nodal harvest (at least 12 nodes) further correlates with improved staging accuracy and survival, as supported by meta-analyses confirming TME's superiority over non-TME approaches in reducing recurrence and enhancing long-term oncologic results.^[83] Comparative data from randomized trials affirm TME's consistency across approaches. The COREAN trial demonstrated equivalent 10-year overall survival (74.1% open TME vs. 76.8% laparoscopic TME) and disease-free survival (59.3% vs. 64.3%) for mid- or low-rectal cancers after neoadjuvant chemoradiotherapy, indicating that minimally invasive TME maintains oncologic efficacy comparable to open surgery.^[84] Recent meta-analyses from the 2020s reinforce TME's established benefits, with local recurrence rates remaining low (under 6%) and survival advantages persisting over historical benchmarks.^[85]

Quality of life and long-term impacts

Total mesorectal excision (TME) for rectal cancer, while effective for oncological control, often leads to functional impairments that affect patients' quality of life. Studies using validated instruments like the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30 and QLQ-CR29) indicate that while global health-related quality of life (HRQoL) generally returns to near-baseline levels within one year post-surgery, domain-specific deficits in bowel, sexual, and urinary functions persist, influencing daily activities and emotional well-being.^[86] These impacts are more pronounced in sphincter-preserving procedures like low anterior resection (LAR) compared to abdominoperineal resection (APR) with permanent stoma, though both approaches present unique challenges.^[87] Bowel dysfunction, commonly manifesting as low anterior resection syndrome (LARS), affects 40-60% of patients undergoing sphincter-preserving TME, with major LARS occurring in up to 54% and involving symptoms such as fecal incontinence (3-79%), urgency (0-69%), and increased stool frequency (10-60%).^[88] These issues typically stabilize within 1-2 years but can endure long-term, impacting social participation and requiring interventions like biofeedback therapy to improve continence and reduce symptom severity.^[86] Sexual and urinary dysfunctions are frequent complications of TME, with rates varying by nerve preservation techniques. In males, impotence occurs in 30-70% of cases, while females experience dyspareunia in 20-40%; urinary dysfunction affects approximately 19-30% overall, often presenting as frequency or incontinence.^[89] Nerve-sparing approaches, such as preservation of the pelvic autonomic nerves, significantly mitigate these risks, reducing sexual dysfunction incidence by up to 50% compared to non-sparing surgery, though complete avoidance remains challenging in advanced tumors.^[90] Psychosocial effects of TME include altered body image, particularly in patients with permanent stomas after APR, leading to embarrassment and reduced social functioning as measured by the EORTC QLQ-CR29 scale, where stoma-related items score higher for distress.^[87] Return to work and daily roles is often delayed, with 20-40% of patients reporting ongoing psychological burden from functional changes and stoma management, though adaptation improves emotional well-being over time.^[86] Long-term follow-up data, including 10-year assessments, reveal that while many patients adapt to functional deficits, 20-30% experience persistent LARS or urogenital issues, resulting in sustained HRQoL reductions in physical and role functioning domains on the EORTC scales.^[86] These enduring effects underscore the need for multidisciplinary support, with studies showing gradual improvement in overall adaptation but highlighting the importance of preoperative counseling on potential lifelong impacts.^[91]

Future directions

Emerging variations and technologies

Refinements in transanal total mesorectal excision (taTME) have focused on optimizing safety and efficacy through variations such as pure transanal approaches versus hybrid techniques that combine transanal and abdominal access. Pure taTME involves complete dissection from below without abdominal assistance, while hybrid taTME incorporates laparoscopic or robotic elements from above to mitigate risks like urethral injury or incomplete mesorectal excision.^[92]^[93] In 2018, Norwegian authorities imposed a moratorium on taTME following reports of elevated local recurrence rates, prompting global scrutiny and refinements in training protocols and patient selection to address technical pitfalls.^[94] Subsequent international registry data and trials, including the 2025 TaLaR study, have demonstrated comparable disease-free survival between taTME and laparoscopic TME, supporting cautious resumption and refinement of the technique in select centers.^[58]^[95] Advancements in robotic surgery for TME, particularly using the da Vinci system, have enhanced precision in pelvic dissection and nerve preservation due to improved visualization and maneuverability in confined spaces.^[96] In the 2020s, integration of artificial intelligence (AI) has further evolved robotic TME through tools for preoperative planning, such as AI-assisted MRI segmentation to delineate the mesorectal fascia and identify optimal surgical planes.^[97] For instance, deep learning models have achieved high accuracy in segmenting loose connective tissue on MRI, aiding surgeons in visualizing safe dissection margins and reducing positive circumferential resection margin rates.^[98] These AI enhancements, demonstrated in robotic-assisted procedures, have shown promise in real-time guidance during surgery, potentially lowering complication rates in complex rectal cancers.^[99]^[100] Organ preservation strategies represent a significant evolution in TME-era management, particularly non-operative approaches for patients achieving complete clinical response to neoadjuvant therapy. The watch-and-wait protocol defers surgery in favor of close surveillance, preserving sphincter function and quality of life for complete responders.^[101] The International Watch & Wait Database (IWWD), aggregating data from over 1,000 patients across multiple institutions by 2023, reports 5-year local regrowth rates of approximately 25% but overall organ preservation in about 75% of cases, with non-inferior oncologic outcomes compared to standard TME.^[102]^[103] This approach, supported by trials like OPRA, emphasizes rigorous endoscopic and imaging follow-up to detect regrowth early, enabling salvage TME when needed.^[104] Fluorescence-guided surgery using indocyanine green (ICG) has emerged as an intraoperative tool to assess bowel perfusion during TME anastomoses, aiming to reduce anastomotic leaks—a common complication in low rectal resections.^[105] ICG, injected intravenously, allows real-time visualization of vascular supply via near-infrared imaging, enabling surgeons to adjust resection margins or reinforce anastomoses based on perfusion adequacy.^[106] Studies in laparoscopic and robotic TME have shown ICG angiography lowers leak rates from 10-15% to under 5% in high-risk cases, with no adverse effects from the dye.^[107] This technology integrates seamlessly with minimally invasive platforms, enhancing decision-making during the critical anastomotic phase.^[108]

Ongoing research and controversies

One significant controversy surrounding total mesorectal excision (TME) involves the safety of transanal TME (taTME), particularly regarding local recurrence rates. Early implementation series reported higher locoregional recurrence rates, such as 12.5% in initial multicenter experiences, which decreased to 3.4% with greater surgeon experience.^[109] However, recent meta-analyses from 2023 to 2025 have demonstrated equivalence in oncologic outcomes between taTME and laparoscopic TME, with 3-year disease-free survival rates of 82.1% for taTME versus 79.4% for laparoscopic approaches in randomized trials.^[58]^[110] Another debate concerns potential overtreatment with TME in early-stage rectal cancer, where radical resection may expose patients to unnecessary morbidity without survival benefits. For stage I disease, neoadjuvant chemoradiation followed by TME is often viewed as excessive, as TME alone achieves excellent outcomes with lower risks of functional impairment.^[111]^[112] Active clinical trials are addressing neoadjuvant strategies to refine TME indications. The PROSPECT trial, reporting primary results in 2023, established noninferiority of neoadjuvant chemotherapy with selective chemoradiation omission compared to standard chemoradiation, favoring TME alone in low-risk locally advanced cases to reduce toxicity while maintaining 5-year disease-free survival.^[113] Updates to ESGAR guidelines in 2024 emphasize standardized MRI protocols for rectal cancer staging, incorporating high-resolution T2-weighted and diffusion-weighted imaging to better assess tumor response and guide TME planning.^[114] Research gaps persist in long-term taTME outcomes, with the COLOR III trial's interim analyses as of 2022 highlighting the need for extended follow-up to confirm durability beyond 3 years, as enrollment continues.^[115] Disparities in low-resource settings exacerbate challenges, where limited access to specialized surgical facilities and multidisciplinary care hinders TME adoption, leading to higher recurrence and poorer survival compared to high-resource environments.^[116] In personalized medicine, genomic predictors such as microsatellite instability and TP53 mutations are underexplored for tailoring TME candidacy, with studies calling for integrated profiling to identify responders to neoadjuvant therapies.^[117] Future challenges include adapting TME to an aging population and rising obesity rates, which complicate feasibility; obese patients face higher intraoperative complications and conversion rates during TME, while older adults experience elevated 30-day mortality post-resection.^[118]^[119] Integration of immunotherapy with TME for MSI-high tumors represents a promising frontier, as immune checkpoint inhibitors in mismatch repair-deficient rectal cancers enable nonoperative management in select cases, potentially sparing TME in up to 50% of responders when combined with total neoadjuvant therapy.^[120]^[121]

References

[1]
The mesorectum in rectal cancer surgery--the clue to pelvic ...
Total excision of the mesorectum has, therefore, been carried out as a part of over 100 consecutive anterior resections. Fifty of these, which were classified ...
[2]
Techniques in Total Mesorectal Excision Surgery - PMC
Advances in the surgical management of rectal cancer have placed the quality of total mesorectal excision (TME) as the major predictor in overall survival.
[3]
Total Mesorectal Excision Technique—Past, Present, and Future - NIH
However, Professor Richard (Bill) Heald popularized and promoted the TME. TME removes the rectal cancer with its primary lymphovascular drainage as an intact ...
[4]
Recurrence and survival after total mesorectal excision for rectal ...
A 7 1/2-year consecutive series is presented from a district hospital with a policy of referring all rectal carcinomas to one surgical firm.Missing: 1982 | Show results with:1982
[5]
A Systematic Review and Meta-Analysis - ScienceDirect.com
Aug 23, 2025 · Total mesorectal excision (TME) with or without neoadjuvant chemoradiotherapy remains the gold standard treatment for rectal cancer.
[6]
Surgical anatomy of the rectum, mesorectum, and pelvic fascia and ...
The rectum is surrounded with the mesorectum that is in turn wrapped by the perirectal fascia. The intraperitoneal part of the rectum is related to the uterine ...
[7]
Detailed and applied anatomy for improved rectal cancer treatment
As part of the alimentary tract, the rectum is surrounded by an adipocyte envelope called “meso”, in which vessels, nerves and lymph nodes are embedded. This ...
[8]
MRI anatomy of the rectum: key concepts important for rectal cancer ...
Jan 18, 2023 · The rectum and surrounding mesorectal fat (the mesorectum) are enveloped by the mesorectal fascia (MRF) and are fixed to the sacrum by the ...
[9]
Essential Anatomy of the Anorectum for Colorectal Surgeons ...
The mesorectum is a fatty tissue encircling the rectum and is a very important structure in a total mesorectal excision for rectal cancer.
[10]
[PDF] Incidence 8 729 833 7.1 Mortality 10 343 817 3.1
Age standardized (World) incidence rates, Rectum, males, all ages ... GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries.
[11]
Colorectal Cancer Risk Factors - CDC
Oct 17, 2024 · Lack of regular physical activity. · A diet low in fruit and vegetables. · A low-fiber and high-fat diet, or a diet high in processed meats.Missing: authoritative | Show results with:authoritative
[12]
Rectal Cancer - StatPearls - NCBI Bookshelf - NIH
Risk factors include: personal or family history of colorectal cancer, adenomatous polyps, and polyps with villous or tubulovillous dysplasia. Patients with ...Missing: authoritative sources
[13]
Colorectal Cancer Stages - American Cancer Society
Jan 29, 2024 · The earliest stage of colorectal cancers is called stage 0 (a very early cancer), and then range from stages I (1) through IV (4).
[14]
Rectal cancer (staging) | Radiology Reference Article
Oct 30, 2025 · Staging of rectal cancer uses the TNM staging system and strongly predicts the success, and rate, of local recurrence following rectal cancer resection.
[15]
Circumferential resection margin | Radiology Reference Article
May 16, 2024 · A margin of ≤1 mm is considered by some to be a negative prognostic factor for local recurrence 2. The prognostic value of the circumferential ...
[16]
Preoperative Radiotherapy Combined with Total Mesorectal ...
The rate of local recurrence at two years was 5.3 percent in the population of 1748 patients who underwent a macroscopically complete local resection. The rates ...
[17]
Local recurrence of rectal adenocarcinoma due to inadequate ...
Nov 1, 1986 · In rectal adenocarcinoma, local recurrence is mainly due to lateral spread of the tumour and has previously been underestimated.
[18]
https://www.sciencedirect.com/science/article/pii/S0140673686926127
[19]
Local recurrence of rectal adenocarcinoma due to inadequate ...
Local recurrence of rectal adenocarcinoma due to inadequate surgical resection. Histopathological study of lateral tumour spread and surgical ...
[20]
The Basingstoke Experience of Total Mesorectal Excision, 1978-1997
ObjectiveTo examine the role of total mesorectal excision in the management of rectal cancer.DesignA prospective consecutive case series.SettingA district.
[21]
12-year follow-up of the multicentre, randomised controlled TME trial
Background: The TME trial investigated the value of preoperative short-term radiotherapy in combination with total mesorectal excision (TME).Missing: neoadjuvant radiation
[22]
Preoperative radiotherapy versus selective postoperative ... - PubMed
Mar 7, 2009 · Our findings provide convincing and consistent evidence that short-course preoperative radiotherapy is an effective treatment for patients with operable rectal ...Missing: therapy | Show results with:therapy
[23]
Patterns of local recurrence in rectal cancer; a study of the ... - PubMed
Aim of the study: In patients from the Dutch TME trial patterns of local recurrence (LR) in rectal cancer were studied. The purpose was to reconstruct the ...Missing: radiation | Show results with:radiation
[24]
Rectal Cancer, Version 2.2018: Clinical Practice Guidelines in ...
The TME approach is designed to radically remove lymphatic drainage regions of tumors located above the level of the levator muscles. The NCCN panel does not ...
[25]
Development and early outcomes of the national training initiative ...
Feb 17, 2020 · This exploratory study demonstrates acceptable early outcomes in a small cohort suggesting that a competency-based multi-modal training programme for TaTME can ...Missing: PROSPECTOR | Show results with:PROSPECTOR
[26]
Rates of circumferential resection margin involvement vary between ...
Methods: In a study involving 608 patients who underwent surgery for rectal cancer in Leeds during the 12-year period 1986 to 1997, the authors examined the ...
[27]
Management of Locally Advanced Rectal Cancer: ASCO Guideline
Aug 8, 2024 · To provide evidence-based guidance for clinicians who treat patients with locally advanced rectal cancer.
[28]
The evolution of rectal cancer treatment: the journey to total ... - NIH
The advent of TME in 1986 significantly reduced the rate of local recurrence in patients with LARC [2]. Around this same time, the Gastrointestinal Tumor Study ...
[29]
Total mesorectal excision - 40 years of standard of rectal cancer ...
The purpose of this article is to point out importance of this surgical procedure. Starting from first attempts to surgically cure rectal carcinoma in the ...Missing: Bill | Show results with:Bill
[30]
https://pubmed.ncbi.nlm.nih.gov/32200705/
[31]
Surgery - ESMO
Partial mesorectal excision and total mesorectal excision are the recommended surgical procedures for rectal cancer [III, A]. Open surgery and minimally ...Missing: 2000 | Show results with:2000
[32]
Multidisciplinary management of elderly patients with rectal cancer
Jul 2, 2021 · Frailty should not be considered a contraindication to surgery in elderly patients with rectal cancer. It is instead a condition that requires a ...
[33]
Rectal Cancer Treatment & Management - Medscape Reference
Sep 30, 2025 · Local excision is increasingly used to treat stage I rectal cancers despite its inferiority to total mesorectal excision, which is the current ...
[34]
Rectal Cancer - Guidelines Detail - NCCN
NCCN Guidelines in Practice™. Earn CME/CE and MOC credits for using the NCCN Guidelines to research your patient care decisions and clinical questions by ...Missing: TME 2000
[35]
Clinical Practice Guidelines for Enhanced Recovery After Colon and ...
Mechanical bowel preparation combined with preoperative oral antibiotics is typically recommended prior to elective colorectal resection. Grade of ...
[36]
Preoperative Preparation | Fundamentals of Rectal Cancer Surgery
Jun 30, 2025 · This planning includes both preoperative counseling and stoma marking by an ostomy nurse (Figure 1). Often, it is helpful for the patient to ...
[37]
[PDF] WOCN Society and ASCRS Position Statement - Colorectal Surgery
Nov 12, 2014 · Preoperatively marking the stoma site allows assessment of the patient's abdomen in multiple positions, which promotes selection of the optimal ...
[38]
https://www.ascrsu.com/ascrs/view/Fundamentals-of-Rectal-Cancer-Surgery/2831010/all/Preoperative_Preparation
[39]
The total mesorectal excision specimen for rectal cancer - NIH
This article reviews the pathological assessment of the TME specimen, including basic definitions, current international guidelines, an approach to evaluating ...
[40]
Pathologic Processing of the Total Mesorectal Excision - PMC - NIH
Quirke P, Steele R, Monson J. et al. MRC CR07/NCIC ... The total mesorectal excision specimen for rectal cancer: a review of its pathological assessment.Missing: original paper
[41]
Review Total mesorectal excision (TME) with laparoscopic approach
Mean operative time 245.3±58.4 min, mean blood loss 203±176 mL. Conversion rate 6.1%. Thirty-days morbidity rate 31.8% without mortality. Anastomotic leaks rate ...
[42]
Laparoscopic versus open total mesorectal excision in rectal cancers
At first, the higher successful resection rate by both approaches and only 8.33% conversion rate for laparoscopic approach reveal the high quality of the ...
[43]
Laparoscopic Total Mesorectal Excision: A Consecutive Series ... - NIH
The conversion rate of 12% compares favorably with the results of laparoscopic colon resections and is superior to the results of laparoscopic TME ...Missing: challenges | Show results with:challenges
[44]
Robotic Total Mesorectal Excision for Rectal Cancer - PMC - NIH
It was considered that the technological advantages of the robotic surgical system can make RTME easier and prevent conversion to open surgery. Conversion rate ...
[45]
Robotic, transanal, and laparoscopic total mesorectal excision ... - NIH
May 28, 2024 · Total mesorectal excision (TME) is the standard surgery for low/mid locally advanced rectal cancer. The aim of this study was to compare three ...
[46]
Comparison of short- and long-term outcomes among laparoscopic ...
Aug 18, 2025 · The REAL trial found robotic TME superior to LapTME in achieving negative CRM margins (4.0% versus 7.2%; difference −3.2%, 95% CI −6.0% to −0.4 ...
[47]
Ileostomy or colostomy for temporary decompression of colorectal ...
The best available evidence for decompression of colorectal anastomosis, either use of loop ileostomy or loop colostomy, could not be clarified from this ...
[48]
Transanal total mesorectal excision (TaTME) in rectal cancer ...
Oct 10, 2023 · This study showed that the TaTME procedure is an effective and safe method for the minimally invasive treatment of middle and low rectal cancers.
[49]
Transanal Total Mesorectal Excision: Description of the Technique
Table 3. Steps of the transanal phase. · 1. Transanal platform insertion and pneumorectum to 12–15 mm Hg · 2. Purse-string distal to the rectal tumor · 3.
[50]
Transanal total mesorectal excision (TaTME): tips and tricks of a new ...
Jul 12, 2017 · Review Article. Transanal total mesorectal excision (TaTME): tips and tricks of a new surgical technique. Elisa Cassinotti1, Giorgio Palazzini ...Missing: 2010 paper
[51]
Clinical Status and Future Prospects of Transanal Total Mesorectal ...
Jan 2, 2022 · In 1982, the first TME was advocated by Bill Heald, which was labeled as a milestone in the history of rectal cancer surgery (1). In 2007, ...
[52]
Transanal total mesorectal excision (taTME) for rectal cancer
Jul 4, 2016 · Since the first taTME resection assisted by laparoscopy was reported in 2010 [13], taTME performed on patients with rectal cancer has showed ...Oncological Outcomes · Subgroup Analyses · Discussion<|control11|><|separator|>
[53]
[PDF] The role of transanal total mesorectal excision (TaTME) in the ...
Nov 18, 2024 · Transanal total mesorectal excision (TaTME) is an innovative surgical approach for treating mid- and low-rectal cancers.
[54]
Transanal vs Laparoscopic Total Mesorectal Excision and 3-Year ...
Jan 23, 2025 · This randomized, open-label, phase 3 clinical trial investigates whether transanal total mesorectal excision is noninferior to laparoscopic ...
[55]
Transanal Endoscopic Platforms: TAMIS versus Rigid Platforms
Feb 28, 2022 · For rigid platforms, the surgeon operates through a rigid 4-cm diameter steel proctoscope of varying lengths that is clamped to the operating ...Missing: GelPort | Show results with:GelPort
[56]
The use of double CO 2 insufflators in transanal total mesorectal ...
In the TaTME procedure, the small surgical field enhances the nuisance problem of rectal billowing. Even minimum changes in pressure are remarkable and ...Missing: GelPort | Show results with:GelPort
[57]
Transanal total mesorectal excision (taTME) for rectal cancer
Transanal total mesorectal excision (taTME) is a surgical approach for low rectal cancer with a learning curve estimated at 40-50 cases.
[58]
Pelvic autonomic nerve preservation in radical rectal cancer surgery
Jul 31, 2016 · This review attempts to evaluate current understanding of the anatomy of pelvic nerves and the differences in outcomes of the various techniques.
[59]
Autonomic nerve preserving total mesorectal excision - PubMed
These changes evolved to include deliberate autonomic nerve preservation as a part of the operation that was ultimately reported as TME with ANP [1]. While it ...
[60]
A prospective study of sexual and urinary function before ... - PubMed
Background: Oncologic resection of rectal cancer has been reported to be associated with a significant (10%-60%) rate of sexual and urinary dysfunction. We ...Missing: incidence | Show results with:incidence
[61]
Urinary and Sexual Disorders After Laparoscopic TME for Rectal ...
... incidence of urinary dysfunction 10–30% and erectile dysfunction 40–60%. Urinary and sexual functions are controlled by the sympathetic nerves that ...<|separator|>
[62]
Neuromonitoring Prevents Anoneorectal Dysfunction in Patients
This trial assessed whether pelvic intraoperative neuromonitoring (pIONM) could improve functional outcomes in patients that underwent total mesorectal ...
[63]
Intraoperative pelvic neuromonitoring based on bioimpedance signals
Aug 3, 2024 · This single-arm prospective study included 30 patients who underwent rectal resection performed with intraoperative neuromonitoring by recording the change in ...
[64]
The effect of the introduction of the ERAS protocol in laparoscopic ...
These results suggest that the introduction of the ERAS protocol in laparoscopic TME leads to a further reduction in length of hospital stay. Keywords: ERAS, ...
[65]
Pain Management in Enhanced Recovery after Surgery (ERAS ...
Multimodal analgesia as part of an ERAS protocol improves postoperative pain control while reducing opiate use.
[66]
Loop Ileostomy Reversal After Colon and Rectal Surgery
Our practice approach is, in general, to reverse diverting ileostomy no less than 12 weeks after the primary operation. General surgery residents and colorectal ...
[67]
Anastomotic leak: are we closer to eliminating its occurrence?
Aug 6, 2018 · Historically anastomotic leak rates are estimated at approximately 1–3% for ileocolic reconstructions, 6–12% for left colon reconstructions, and ...
[68]
Risk factors for early complications after laparoscopic total ...
The overall postoperative complication rate was 22.3%, and the complications included wound infection (5.2%), pneumonia (4.5%), urethritis (3.9%), anastmosis ...
[69]
Impact of a diverting ileostomy in total mesorectal excision with ... - NIH
Oct 18, 2022 · Stoma-related complications such as dermatitis, stoma dysfunction or high output stoma occur in more than half of the cases and result in more ...
[70]
Sexual and urinary dysfunction after proctectomy for rectal cancer
With the adoption of the technique of TME, the rate of sexual dysfunction has decreased to the range of 10 to 35% and that of urinary dysfunction, 0 to 5%, ...
[71]
Management of anastomotic leakage after rectal surgery - NIH
Contrast medium at the site of the anastomosis is crucial in detecting anastomotic leakage with CT imaging after colorectal surgery. Int J Colorectal Dis ...Missing: TME | Show results with:TME
[72]
Incidence and Mortality of Anastomotic Dehiscence Requiring ... - NIH
A total of 1309 patients were confirmed in this analysis, indicating that 63.1% (1309 of 2075) of ADs after resection for rectal carcinoma require reoperation.Results · Included Studies · Discussion
[73]
Surveillance and Survivorship Care of Patients After Curative ...
Mar 18, 2025 · Surveillance colonoscopy is typically recommended 1 year after completing treatment for stage II/III colon or rectal cancer. In patients with an ...
[74]
Nationwide in‐hospital mortality rate following rectal resection for ...
The crude in‐house mortality rate ranged from 5·3 per cent in hospitals in the lowest volume category to 2·6 per cent in the highest‐volume centres (P < 0·001) ...
[75]
Recurrence and survival after mesorectal excision for rectal cancer
Results: The cumulative 3-year local recurrence rate was 11 per cent after mesorectal excision compared with 30 per cent after conventional surgery (hazard ...Missing: comparison | Show results with:comparison
[76]
The TME trial after a median follow-up of 6 years: increased local ...
Five-year local recurrence risk of patients undergoing a macroscopically complete local resection was 5.6% in case of preoperative radiotherapy compared with ...
[77]
A Prognostic Nomogram for T3N0 Rectal Cancer After Total ...
The 5-year OS of T3N0 patients after surgery is 74–84%, and such a high survival rate means that not all patients (especially those who underwent complete ...
[78]
Circumferential resection margin as a prognostic factor after rectal ...
This study aimed to investigate circumferential resection margin (CRM) as a prognostic factor for long‐term oncologic survival after rectal cancer surgery.Missing: 1980s | Show results with:1980s
[79]
COREAN trial: long-term clinical impact of laparoscopic surgery in ...
Mar 30, 2022 · With a median follow-up of 143 (IQR, 122–156) months, data analysis showed similar rates of overall survival (74.1% for the open surgery group ...
[80]
A systematic review and meta‐analysis of oncological outcomes ...
Apr 8, 2024 · Functional complaints and quality of life after transanal total mesorectal excision: a meta-analysis. Br J Surg. 2020; 107(5): 489–498.Abstract · INTRODUCTION · METHOD · RESULTS
[81]
Is my life going to change?—a review of quality of life after rectal ...
Long term follow-up studies showed that the symptoms present 1 year after surgery ... Quality of life after total mesorectal excision for rectal cancer.
[82]
Quality of Life After “Total Mesorectal Excision (TME)” for Rectal ...
Quality of Life After “Total Mesorectal Excision (TME)” for Rectal ... Quality of life in long-term survivors of adult-onset cancers. J Natl Cancer ...
[83]
Low anterior resection syndrome - PMC - NIH
The reported prevalence of major LARS is about 40%–60%. , The LARS ... The incidence and risk factors of low anterior resection syndrome (LARS) after ...
[84]
Assessment of sexual and voiding function after total mesorectal ...
Multiple regression analysis of factors affecting postoperative sexual dysfunction showed that age older than 60 years (sexual desire, P = 0.019), within six ...
[85]
Prospective study of sexual dysfunction in men with rectal cancer
Our data show that nerve sparing technique can reduce the incidence of sexual dysfunction. Unfortunately, the technique is not applicable in every patient.
[86]
Long-term Quality of Life and Functional Outcome of Patients With ...
May 1, 2023 · Long-term Quality of Life and Functional Outcome of Patients With ... total mesorectal excision. In general, patients observed by a ...
[87]
Comparison of transanal total mesorectal excision (TaTME) versus ...
A total of 20 patients (12 males and 8 females) were analyzed in this study, including 11 cases (55 %) of pure TaTME and 9 cases (45 %) of hybrid TaTME.
[88]
Limitations and Concerns with Transanal Total Mesorectal Excision ...
Better visualization of the lower rectum could lead to a more complete total mesorectal excision (TME) and less circumferential resection margin (CRM) positive ...Technical Aspects · Urologic Lesions · Oncological Outcomes
[89]
Norwegian moratorium on transanal total mesorectal excision
Norwegian moratorium on transanal total mesorectal excision. Br J Surg. 2019 Aug;106(9):1120-1121. doi: 10.1002/bjs.11287. Authors. S G Larsen , F Pfeffer ...
[90]
Transanal vs Laparoscopic Total Mesorectal Excision and 3-Year ...
Jan 23, 2025 · The TaLaR trial indicates that transanal TME is as safe and effective as laparoscopic TME for patients with mid-low rectal cancers, measured by ...
[91]
Total Mesorectal Excision with New Robotic Platforms - MDPI
Oct 25, 2024 · This scoping review aimed to assess the role and adoption of these emerging robotic systems in performing TME for rectal cancer surgery.
[92]
Artificial Intelligence-Based Total Mesorectal Excision Plane ...
May 1, 2022 · We successfully developed a total mesorectal excision plane image-guided navigation system based on an areolar tissue segmentation approach with high accuracy.
[93]
Automated segmentation by deep learning of loose connective ...
Oct 27, 2021 · We aimed to develop an AI model that achieves LCTF predictions which are highly convincing to expert surgeons and help surgeons visualize safe ...
[94]
Use of artificial intelligence in total mesorectal excision in rectal ...
Dec 8, 2023 · AI has the potential to revolutionize TME surgery by providing real-time surgical guidance, preventing complications, and improving training.
[95]
Technical implementation and feasibility of the world's first artificial ...
Oct 22, 2025 · Its application in colorectal surgery has already been demonstrated in robotic total mesorectal excision for rectal cancer, where AI ...Missing: 2020s | Show results with:2020s
[96]
International consensus recommendations on key outcome ... - Nature
Aug 4, 2021 · Organ preservation constitutes a paradigm shift in the management of patients with rectal cancer. One of the main reasons for exploring ...
[97]
Watch and wait after neoadjuvant treatment in rectal cancer ...
Mar 27, 2023 · A total of 1010 patients were identified. At first reassessment, 608 patients had a cCR; 402 had a cCR at later reassessment. Median follow-up ...
[98]
The Risk of Distant Metastases in Patients With Clinical Complete ...
Patients: A total of 793 patients (47 institutions) with rectal cancer and clinical complete response to neoadjuvant treatment from the International Watch & ...
[99]
Non-operative management for rectal cancer - PMC - NIH
Finally, the recently published OPRA trial demonstrated impressive 3-year colostomy-free survival of 53% with their watch-and-wait strategy. As we become more ...
[100]
Indocyanine Green Fluorescence Guided Surgery in Colorectal ...
The terms 'colorectal', 'colon', 'rectal', 'indocyanine green', 'ICG', and 'fluorescence' were used combined with the Boolean operators AND/OR in order to ...
[101]
Perfusion outcomes with near-infrared indocyanine green imaging ...
May 9, 2024 · Perfusion outcomes with near-infrared indocyanine green imaging system in laparoscopic total mesorectal excision for mid-rectal or low-rectal ...
[102]
Indocyanine Green Fluorescence Imaging in Prevention of ...
Mar 5, 2025 · Importance Performing a bowel anastomosis is a critical step in colorectal resection. Assessing the risk of anastomotic leakage remains ...
[103]
Intraoperative fluorescence angiography with indocyanine green to ...
Jul 18, 2025 · IntAct: intra-operative fluorescence angiography to prevent anastomotic leak in rectal cancer surgery: a randomized controlled trial. Colorectal ...Missing: TME | Show results with:TME
[104]
The learning curve of transanal total mesorectal excision for rectal ...
Transanal total mesorectal excision (TaTME) was introduced to improve both clinical and long‐term outcomes for patients with low and mid rectal cancer [1].
[105]
Multidisciplinary treatment strategy for early rectal cancer
Dec 27, 2021 · Neoadjuvant CRT in patients with stage I rectal cancer is considered an overtreatment. This is due to the fact that TME surgery alone is ...
[106]
Early Rectal Cancer: Advances in Diagnosis and Management ...
For patients with early-stage rectal cancer, rectal resection with TME may represent overtreatment in certain cases [47]. Radical resection procedures, such ...Early Rectal Cancer... · 2. Staging Of Rectal Cancer · 5. Management Options
[107]
https://jamanetwork.com/journals/jamasurgery/fullarticle/2830866
[108]
MRI for Rectal Cancer: Updates and Controversies—AJR Expert ...
Rectal MRI is a critical tool in the care of patients with rectal cancer, having established roles for primary staging, restaging, and surveillance.
[109]
Transanal total mesorectal excision for rectal cancer: it's come a ...
Aug 29, 2022 · The Norwegian moratorium on TaTME in 2019 singlehandedly led to a temporary ban on TaTME in that region. In that paper, Larsen et al. [24] ...Missing: resolved | Show results with:resolved
[110]
Colon and Rectal Cancer Management in Low-Resource Settings
Sep 13, 2022 · In this article, we will review barriers to care, screening and treatment approaches, and ongoing developments in CRC care in low-resource settings.
[111]
Genomic and transcriptomic determinants of response to ... - NIH
Feb 15, 2023 · In summary, we have presented a comprehensive genomic analysis of rectal cancer in a large cohort of patients with detailed clinicopathological ...Missing: personalized | Show results with:personalized
[112]
The Impact of Obesity on Intraoperative Complications in Rectal ...
May 30, 2025 · Obese patients experienced significantly higher intraoperative complication rates, a greater need for conversion to open surgery, and increased ...
[113]
Controversies of total mesorectal excision for rectal cancer in elderly ...
After major resectional treatment, elderly patients with rectal cancer have an increased 30-day and 6-month mortality compared with younger patients.Missing: contraindications | Show results with:contraindications
[114]
Integrating Immune Checkpoint Inhibitors With Total Neoadjuvant ...
Aug 24, 2025 · Although immune checkpoint inhibitors (ICIs) show remarkable efficacy in mismatch repair-deficient/MSI-H colorectal cancer, their role in ...
[115]
Nonoperative Management of Mismatch Repair–Deficient Tumors
Apr 27, 2025 · As neoadjuvant therapy, immune checkpoint blockade has resulted in elimination of the primary tumor in patients with colorectal cancers, and for ...