Transabdominal Total Mesorectal Excision Research Articles

Customized Denonvilliers' Fascia Excision: An Advanced Total Mesorectal Excision Technique for Anteriorly Located Rectal Cancer.

The role of Denonvilliers' fascia in achieving a negative circumferential resection margin during anterior total mesorectal excision has been controversial. Opinions on whether to dissect in the anterior or posterior surgical plane varies among researchers. We performed total mesorectal excision with selective en bloc resection of Denonvilliers' fascia based on preoperative MRI staging, preoperative clinical tumor stage, and tumor level in selected patients with anterior rectal tumors adherent to Denonvilliers' fascia. Between March and August 2021, 5 patients who underwent robotic (n = 4) and laparoscopic (n = 1) total mesorectal excision for anteriorly located low rectal adenocarcinomas after neoadjuvant chemoradiotherapy were enrolled in this study. Transabdominal total mesorectal excision dissection is performed by changing to a plane anterior to Denonvilliers' fascia, with partial or total excision tailored to the tumor level and depth of invasion as a further step in circumferential resection margin clearing. Customized excision of Denonvilliers' fascia was performed by dissecting through the extramesorectal plane. This anterior plane permits resection of Denonvilliers' fascia, exposing the prostate and seminal vesicles. Two tumors were located at the seminal vesicle level and 3 were found at the prostate level. The mean distance from the anal verge to the distal margin of the tumor was 4.8 ± 0.9 cm. Denonvilliers' fascia was preserved in 1 patient and partially excised in 4. Customized Denonvilliers' fascia excision was performed in 3 robotic ultralow anterior resections with coloanal anastomosis, 1 laparoscopic ultralow anterior resection with coloanal anastomosis, and 1 robot-assisted abdominoperineal resection. The circumferential resection margins in all patients were negative. Anterior dissection in front of Denonvilliers' fascia can be selectively performed during total mesorectal excision based on preoperative planning, tumor location, and clinical tumor stage. Preoperative MRI and magnified operative views in minimally invasive platforms provide access to more precise surgical planes for clear circumferential resection, achieving optimal functional outcomes and oncological safety.

Quality of life and functional outcomes after transanal total mesorectal excision for rectal cancer-results from the implementation period in Denmark.

The standard operation for mid- and low rectal cancer total mesorectal excision (TME) is routinely performed as minimally invasive surgery. TME is associated with temporary or permanent functional impairment of pelvic organs, causing reduced quality of life (QoL). Concerns have been raised that the newest minimally invasive approach, transanal TME (TaTME), may further reduce urogenital and anorectal functions. To determine if functional outcomes affecting QoL are altered after TaTME. Primary end-point is the impact of TaTME on QoL and functional outcomes. Secondary end-point is assessing differences in QoL and functional outcomes after TME surgery from below (TaTME) or above (transabdominal TME). Observational study consisting of prospectively registered self-reported questionnaire data collected at baseline and follow-ups after TaTME. All patients who underwent TaTME during the Danish national implementation phase were included. Central surveillance of the implementation included questionnaires concerning QoL and functional outcomes. Analyses of functional results from the Danish cohort of the ROLARR trial (Jayne et al. in JAMA 318:1569-1580,(2017) are reported separately for perspective, representing the transabdominal approach to TME, i.e., laparoscopic- or robotic-assisted TME (LaTME/RoTME). Applied questionnaires include EORTC QLQ-C30, SF-36, LARS, ICIQ-MLUTS, ICIQ-FLUTS, IPSS, IIEF, SVQ, and FSFI. A total of 115 TaTME procedures were registered August 2016 to April 2019. LaTME/RoTME patients (n = 92) were operated on January 2011 to September 2014. A temporary postoperative decrease of QoL (global health status and functional scales) was observed, yet long-term results were unaffected by surgery in both groups. In TaTME patients, the anorectal dysfunction increased significantly (p < 0.001) from preoperative baseline to 13.5months follow-up, where 67.5% (n = 52) reported major LARS symptoms. Urinary function was not significantly impaired after TME regardless of technique. The paucity of responses concerning sexual function precludes conclusions. Although an initial reduction in QoL after TME occurs, it normalizes within the first year postoperatively. In concurrence with international results, we found that significant anorectal dysfunction is common after TaTME. No data on anorectal function was available for LaTME/RoTME patients for comparison. We found no indications that transanal TME is inferior to transabdominal TME surgery concerning urogenital functions or health-related QoL.

The "terminal line": a novel sign for the identification of distal mesorectum end during TME for rectal cancer.

BackgroundAlthough the clinical importance of complete, intact total mesorectal excision (TME) is the widely accepted standard for decreasing local recurrence of rectal cancer, the residual mesorectum still represents a significant component of resection margin involvement. This study aimed to use a visible intraoperative sign to detect the distal mesorectal end to ensure complete inclusion of the mesorectum and avoid unnecessary over-dissection.MethodsThe distal mesorectum end was investigated retrospectively through a review of 124 operative videos at the Union Hospital of Fujian Medical University (Fujian, China) and Cleveland Clinic (Ohio, USA) by two independent surgeons who were blinded to each other. Furthermore, 28 cadavers and 44 post-operative specimens were prospectively examined by hematoxylin and eosin (H&E) staining and Masson's staining to validate and confirm the findings of the retrospective part. Univariate and multivariate analyses were carried out to detect the independent factors that can affect the visualization of the distal mesorectal end.ResultsThe terminal line (TL) is the distal mesorectal end of the transabdominal and transanal TME (taTME) and appears as a remarkable pearly white fascial structure extending posteriorly from 2 to 10 o'clock. Histopathological examination revealed that the fascia propria of the rectum merges with the presacral fascia at the TL, beyond which the mesorectum ends, with no further downward extension. In the retrospective observation, the TL was seen in 56.6% of transabdominal TME and 56.0% of taTME operations. Surgical approach and tumor distance from the anal verge were the independent variables that directly influenced the detection of the TL (P = 0.03 and P = 0.01).ConclusionThe TL is a visible sign where the transabdominal TME should end and the taTME should begin. Recognition of the mesorectal end may impact the certainty of complete mesorectum inclusion. Further clinical trials are needed to confirm the preliminary findings.

A systematic review and meta-analysis of robotic-assisted transabdominal total mesorectal excision and transanal total mesorectal excision: which approach offers optimal short-term outcomes for mid-to-low rectal adenocarcinoma?

Resection of low rectal adenocarcinoma can be challenging in the narrow pelvis of male patients. Transanal total mesorectal excision (TaTME) appears to offer technical advantages for distal rectal tumours, and robotic-assisted transabdominal TME (rTME) was introduced in effort to improve operative precision and ergonomics. However, no study has comprehensively compared these approaches. The aim of the present study was to perform a systematic review of the literature to compare postoperative short-term outcomes in rTME and TaTME. A systematic online search (1974-July 2020) of MEDLINE, Embase, web of science and google scholar was conducted for trials, prospective or retrospective studies involving rTME, or TaTME for rectal cancer. Outcome variables included: hospital stay; operation duration, blood loss; resection margins; proportion of histologically complete resected specimens; lymph nodes; overall complications; anastomotic leak, and 30-day mortality. Sixty-two articles met the inclusion criteria, including 37 studies (3835 patients) assessing rTME resection, 23 studies (1326 patients) involving TaTME and 2 comparing both (165 patients). Operating time was longer in rTME (309.2min, 95% CI 285.5-332.8) than in TaTME studies (256.2min, 95% CI 231.5-280.9) (p = 0.002). rTME resected specimens had a larger distal resection margin (2.62cm, 95% CI 2.35-2.88) than in TaTME studies (2.10cm, 95% CI 1.83-2.36) (p = 0.007). Other outcome variables did not significantly differ between the two techniques. rTME provides similar pathological and short-term outcomes to TaTME and both are reasonable surgical approaches for patients with mid-to-low rectal cancer. To definitively answer the question of the optimal TME technique, we suggest a prospective trial comparing both techniques assessing long-term survival as a primary outcome.

Prediction of transabdominal total mesorectal excision difficulty according to the angle of pelvic floor muscle.

Total mesorectal excision (TME) is challenging to perform in a deep, narrow pelvis. While previous studies used pelvimetry to assess bony pelvic structures, there is no consensus on exact definition of deep, narrow pelvis. We hypothesized that the shape of pelvic floor muscle may impact the performance of transabdominal pelvic dissection. We aimed to evaluate which parameters of the shape of pelvic floor muscle impact the difficulty of TME and present a predictive reference value for TME difficulty. From January 2015 to December 2015, 85 consecutive patients who had undergone curative resection for middle to lower rectal cancer were retrospectively studied. Pelvimetry was performed using preoperative T2-weighted magnetic resonance imaging. Predictive factor analysis for surgical duration was studied using linear regression. Mann-Whitney U test, comparing surgical duration between two groups classified by predictive factor, was used for the analysis of reference value. Multivariate analysis revealed that body mass index, protective stoma, number of surgeon, and incline angle of pelvic floor muscle (β) were independent predictors of surgical duration. Test statistics of Mann-Whitney U for the difference in surgical duration between groups above and below a β of 54° were maximized. The incline angle of pelvic floor muscle is an independent predictor of surgical duration. In patients with steeper incline of PFM, transabdominal TME is expected to be difficult. This index is novel, but needs to be further validated.

Last critical step for transanal total mesorectal excision: anastomosis

Colorectal anastomosis remains a key aspect in mid- and lower-rectal surgery, particularly in patients who are male, obese, status post neoadjuvant chemoradiation, or possess narrow pelvic anatomy. Transanal total mesorectal excision (taTME) and transabdominal total mesorectal excision (TME) both primarily allow position of the tumor to dictate whether circular stapling or hand-sewing is utilized to achieve anastomosis. Given that taTME only requires a single circular stapler to achieve anastomosis, it consequently decreases the risk of jeopardizing blood supply to the anastomotic site. Should transanal hand-sewing be pursued, numerous points in performing the purse-string suture warrant particular attention: (1) Before suturing, separate the distal rectum to be anastomosed from the surrounding tissues, and ensure the full-layer suture of the distal purse-stitched suture. (2) It is recommended that beginners complete the suturing process under direct visualization without removing the transanal platform. (3) Commonly used anastomosis designs include end-to-end, side-to-end, J-pouch, or coloplasty, depending on patient characteristics and surgeon preferences. Our single-institution clinical experience suggests that taTME patients who underwent neoadjuvant chemoradiation or transanal hand-sewn anastomosis should still have a temporary colostomy created. To date, literature has yet to demonstrate the superiority of taTME anastomosis outcomes. This publication aims to point out anastomosis techniques and safety pointers, as well as clinical experiences.

Transanal Endoscopic and Transabdominal Robotic Total Mesorectal Excision for Mid-to-Low Rectal Cancer: Comparison of Short-term Postoperative and Oncologic Outcomes by Using a Case-Matched Analysis.

PurposeThis study aimed to compare short-term postoperative and oncologic outcomes of a transanal endoscopic total mesorectal excision (TME) to those of a transabdominal robotic TME.MethodsA total of 62 patients with rectal cancer underwent transanal (n = 26) or robotic (n = 36) TME between June 2013 and December 2014. After case-matching by tumor location and TNM stage, 45 patients were included for analysis. The median follow-up period was 21.3 months. Operative, histopathologic and postoperative outcomes and recurrences were analyzed.ResultsPatients younger than 60 years of age were more frequently observed in the robotic TME group (75.0% vs. 47.6%, P = 0.059), but tumor location, cT and cN category, and preoperative chemoradiotherapy were not different between the 2 groups. Estimated blood loss was greater in the transanal group (283 mL vs. 155 mL, P = 0.061); however, the operation time and the rate of a diverting ileostomy and subsequent ileostomy repair were not different between the groups. The proximal resection margin was longer in the transanal TME group (20.8 cm ± 16.0 cm, P = 0.030), but the distal resection margins, involvements of the circumferential resection margin, TME quality, numbers of retrieved lymph nodes, postoperative complications, including anastomotic leak and voiding difficulty, and recurrence rates for the 2 groups were not statistically different.ConclusionTransanal endoscopic and transabdominal robotic TME showed similar histopathologic and postoperative outcomes with the exception of the estimated blood loss and the proximal resection margin for a select group of patients.

Whether the transanal total mesorectal excision can achieve a real total mesorectal excision

The total mesorectal excision (TME) developed by Heald in 1982, is the present gold standard treatment of middle and low rectal cancer. However, traditional transabdominal TME remains a technically demanding procedure in patients with a narrow pelvis, bulky tumors, or obesity. To overcome the technical difficulties associated with transabdominal rectal dissection, transanal total mesorectal excision (TaTME) has recently been introduced. However, can TaTME achieve comparable outcomes in comparison with transabdominal TME? Is the distal margin of the mesorectum sufficient? Where is the sign of distal margin of mesorectum? Can the circumferential margin (CRM) and specimen quality be guaranteed? The aim of this comment was to discuss whether the TaTME can achieve a real TME from the following aspects: the principles of transabdominal TME, current published TaTME clinical trials, and the anorectal and pelvic anatomy. Key words: Rectal neoplasms; Total mesorectal excision; Transanal total mesorectal excision; Terminal line

Short- and Mid-Term Outcomes after Endoscopic Transanal or Laparoscopic Transabdominal Total Mesorectal Excision for Low Rectal Cancer: A Single Institutional Case-Control Study

Transabdominal laparoscopic proctectomy (LAP) for rectal cancer was associated with postoperative recovery improvement. Early studies showed favorable short-term results of endoscopic transanal proctectomy (ETAP), with low conversion rates to open procedures. We aimed to compare efficacy, morbidity, and functional outcomes of ETAP to standard LAP for low rectal cancer. From 2008 to 2013, 72 consecutive patients received proctectomy and coloanal manual anastomosis for low rectal adenocarcinoma. Thirty-four patients had transanal endoscopic proctectomy, and 38 patients underwent the standard laparoscopic procedure. When compared with the LAP group, the ETAP group demonstrated a lower conversion rate to open procedures (23.7% vs 2.9%, respectively; p= 0.015), shorter in-hospital stays (9 vs 8 days, respectively; p= 0.04), and a lower readmission rate (13.2% vs 0%; p= 0.03). Overall postoperative morbidity rates for the LAP and the ETAP groups (36.8% vs 32.4%, respectively; p= 0.69) and functional results (Kirwan score 1/2, 73.7% vs 73.5%, respectively; p=0.85) were comparable; additionally, we found similar oncologic quality criteria (R1 resection 10.5% vs 5.9%, respectively; p= 0.68; grade 3 mesorectal integrity 52.6% vs 55.9%, respectively; p= 0.66). Disease-free survival of 24 months (Kaplan-Meier estimation) was comparable in the 2 groups: 86% in the ETAP group vs 88% in the LAP group; p= 0.91. At the date of last follow-up, 91.2% of ETAP patients and 92.1% of LAP patients were free of stoma. The endoscopic transanal approach could facilitate mesorectal excision and improve short-term outcomes without impairing the oncologic quality of the resection or mid-term functional and oncologic results.

Transanal total mesorectal excision (taTME) for cancer located in the lower rectum: Short- and mid-term results

BackgroundLaparoscopic trans-abdominal total mesorectal excision is technically demanding. Transanal Total Mesorectal Excision (taTME) is a new technique which seems to provide technical advantages. This study describes the results of taTME in a consecutive series of patients with low rectal cancer. MethodsFrom January 2012 to December 2013, a consecutive series of 26 patients with low rectal cancer underwent laparoscopic taTME with coloanal anastomosis. cT4 or Type II-III rectal cancer (according to Rullier's classification) were contraindications to taTME. After anal sleeve mucosectomy, the rectal wall was transected at the ano-rectal junction. A single-access multichannel port was inserted in the anal canal. taTME was performed from down to up until the sacral promontory posteriorly and the Pouch of Douglas anteriorly were reached. A laparoscopic trans-abdominal approach was used to complete the left colon mobilization. ResultsSixteen patients (61.5%) were male. The mean distance of the rectal cancer from the anal verge was 4.4 cm (range 3–6). Nineteen patients (73.1%) received long-course neoadjuvant radiotherapy. At final pathology, resection margins were negative in all the patients: the mean distal and radial resection margins were 19 mm and 11.2 mm, respectively. TME was complete in 23 patients (88.5%) and nearly complete in three. Postoperative mortality was 3.8%. The overall morbidity rate was 26.9% (7 patients): two patients (7.7%) had an anastomotic leakage (Dindo I-d). After a mean follow up of 23 months, no patients have developed a local recurrence. Conclusionslaparoscopic taTME allow wide resection margins and good quality TME.

The Red Rectum (Carpet villous adenoma of the rectum)

Carpeted villous adenomas of rectum may be extensive and not suitable for transanal excision or Endoscopic mucosal resection. We present a case of such lesion extending from anorectal junction to rectosigmoid region. After biopsy and staging, this was managed by a sphincter saving procedure, i.e. a combination of transabdominal total mesorectal excision and transanal intersphincteric dissection, with acceptable functional outcome with 8 years of follow up.

Combination of trans-anal intersphincteric resection and trans-abdominal total mesorectal excision for anus-retained ultra-low rectal tumors

To study the combination of trans-anal intersphincteric resection and transabdominal total mesorectal excision for anus-retained ultra-low rectal tumors. Clinical data of 34 ultra-low rectal tumor patients without external anal sphincter involved, who underwent the combination surgery, were retrospectively analyzed. The distance from the distal incisal margin of the rectum to the inferior margin of the tumor ranged from 1.8 cm to 3.0 cm on an average of 2.1 cm. For pathological types, there were 23 cases of adenocarcinoma (9 well differentiated and 14 moderately differentiated), 1 papillary carcinoma, 2 rectal stromal tumor, 5 rectal villous adenoma with neoplasia and 3 giant villous adenoma. For pathological stages, there were 18 cases at stage pTNM I, 5 at IIA, 1 at IIB, 4 at IIIA, 1 at III and for T grading, there were 15 cases at stage T1, 5 at T2, 8 at T3, 1 at T4. In these 34 patients, there were 3 cases with postoperative anastomotic stenosis, 2 with postoperative anastomotic rupture, 2 with rectovaginal fistula and no operative death. Because of the dysfunction of bowel control, bowel frequency varied from 3 to 12 in the early stage after operation, but with the recovery of anus function, bowel frequency decreased and ranged form 1 to 5 times a day and the time of formed bowel control could be more than 5 min in 6-12 months after operation. However, patients underwent total resection of internal anal sphincter still suffered from incontinence of loose stool after 1 year. After operation, anastomotic recurrence was found in 1 case in 5 months, liver metastasis in 1 case in 10 months and 28 months respectively, cardiac sudden death in 1 case in 26 months. The combination of trans-anal ISR and trans-abdominal TME for anus-retained ultra low rectal tumor is not only coincident with radical tumor principle but also retains the function of anus, on the premise of the strict indication.