Anatomical considerations for transanal minimal-invasive surgery: the caudal to cephalic approach

A novel perspective on constipation secondary to sigmoidocele: a retrospective study

PURPOSE

Sigmoidocele, which is a type of obstructed defecation syndrome (ODS), is a peritoneal hernia of the pelvic floor that has been seldom studied individually. This study investigated the anatomic characteristics of sigmoidocele based on imaging features.

METHODS

This retrospective cohort population comprised adult patients with ODS who underwent defecography between December 2017 and July 2020. Sigmoidocele was classified based on existing criteria. Novel radiological parameters including the vertical distance descended by the sigmoid colon from rest to maximum straining (RMS) and from the inferior border of the sigmoid colon to the superior border of the rectum at maximum straining (MSR) were measured.

RESULTS

Among 275 patients with sigmoidocele, 251 (91.6%) were female. The mean age was 51.53±12.99 years. We classified 26, 205, and 44 cases as grades I, II, and III, respectively. Patients with more severe sigmoidocele had greater sigmoid colon mobility (RMS: 19.13±8.54 mm, 34.45±14.51 mm, and 48.70±20.05 mm for grades I, II, and III, respectively; p < 0.001) and more pronounced compression of the rectum by the sigmoid colon at maximum straining (MSR: 35.23±8.44 mm, 26.33±13.29 mm, and 15.18±18.00 mm, respectively; p < 0.001). We regrouped the patients based on sigmoid colon alignment. Type L patients had the most severe constipation.

CONCLUSION

Our study presents a novel sigmoidocele classification. The anatomic appearance and location of the herniated sigmoid colon observed using fluoroscopy during defecation may help improve the clinical awareness of ODS caused by sigmoidocele.

Incidence and Risk Factors of Surgical Complications and Anastomotic Leakage After Transanal Total Mesorectal Excision for Middle and Low Rectal Cancer

PURPOSE

Transanal total mesorectal excision (taTME) is a promising surgical procedure for middle and low rectal cancer; however, it is linked to significant morbidity. This study aimed to determine the incidence of postoperative surgical complications and anastomotic leakage following taTME and to identify their associated risk factors.

METHODS

The prospective clinical data of 114 patients, who underwent taTME and primary anastomosis for mid-low rectal cancer between November 2016 and June 2022, were retrospectively analyzed. Univariate and multivariate analyses were performed to identify clinical characteristics and risk factors for predicting surgical complications and anastomotic leakage.

RESULTS

Surgical complications occurred in 40 (35.1%) patients within the first 30 days following surgery. Based on the Clavien-Dindo classification, minor complications (Clavien-Dindo grades I + II) accounted for 30.7%, while major complications (Clavien-Dindo grades III + IV) accounted for only 4.4%. None of the patients died within 30 days. The incidence of anastomotic leakage was 15.8%: 4.4% as grade A (5 cases), 9.6% as grade B (11 cases), and 1.8% as grade C (2 cases). Preoperative T3-4 was identified as an independent risk factor for surgical complications (p = 0.031) by multivariate analysis. American Society of Anesthesiology score ≥ 3 (P = 0.021) and incomplete total mesorectal excision specimens (P = 0.030) were significantly associated with the risk of anastomotic leakage.

CONCLUSIONS

In this study, the incidence of surgical complications and anastomotic leakage in taTME aligned with previously reported rates. Preoperative T3-4 was significantly associated with surgical complications. American Society of Anesthesiology score ≥ 3 and incomplete TME specimens independently increased the risk of anastomotic leakage.

Transanal versus laparoscopic total mesorectal excision: a comparative study of long-term oncological outcomes

BACKGROUND

Transanal total mesorectal excision (TaTME) is the most recent approach developed to improve pelvic dissection in surgery for mid and low rectal tumors. There are still inconsistencies regarding the technique's oncological results. The aim of this study was to analyze clinical and oncological outcomes of the learning curve of TaTME in comparison to laparoscopic TME (lapTME).

METHODS

Rectal cancer patients who had TaTME and lapTME in two Portuguese colorectal units between March 2016 and December 2018 were eligible. Primary endpoints were 5-year overall survival, disease-free survival, and local recurrence. Secondary endpoints were clinical and pathological outcomes.

RESULTS

Forty-four patients underwent TaTME (29 men) and 39 lapTME (27 men) with a median age of 69 and 66 (p = 0.093), respectively. No differences were observed concerning baseline characteristics, emphasizing their comparability. In the TaTME group, there were more hand-sewn anastomosis (0 lapTME versus 7 TaTME, p = 0.018) with significantly less distance to the dentate line (40 mm lapTME versus 20 mm TaTME, p = 0.005) and significantly more loop ileostomies performed (28 lapTME versus 41 TaTME, p = 0.001). There were no differences in post-operative mortality, morbidity, readmissions, and stoma closure. Groups were similar in relation to specimen quality, margins, and resectability; however, TaTME had a significantly higher node yield (14 lapTME versus 20 TaTME, p = 0.002). Finally, no disparities were noted in oncological outcomes, namely local and distant recurrence, 5-year overall survival, and disease-free survival.

CONCLUSIONS

Even with the disadvantage of the learning curve of a new technique, TaTME appears to be comparable to lapTME, with similar long-term oncological outcomes. It has, however, a demanding learning curve, significant risk for morbidity and should be used only for selected patients.

Re-exploring the pelvic neuroanatomy from a new perspective and a potential guidance for TaTME: a "bottom-up" approach

Neuro-anatomy of the perineum has gained renewed attention due to its significance in the transanal procedures for rectal cancer (eg TaTME). Surgeons embarking on this technique must have sophisticated knowledge and a precise anatomical understanding of the perineum before proceeding with this reversed rectal approach. We report anatomical observations deriving from a relevant experience in the colorectal surgery field. The collective multicenter experience of the present study is clinically relevant and based on the rectal and transanal resections performed in colorectal centers of excellence from Greece, UK, and Italy over the last 10 years (2011-2020). From the original anatomical and intraoperative observations derived from collective cases operated by this multicenter group of colorectal surgical centers in three European countries, data were retrieved and analyzed in collaboration with specialist researchers of human anatomy and interpreted for their clinical significance and potential use for preoperative planning and intraoperative guidance during TaTME. This descriptive article demonstrates in detail the neurogenic pathways encountered in the perineum and pelvic cavity during transanal procedures. Specific anatomical and topographic implications are also included serving as a guide for colorectal surgeons to perform a nerve-sparing procedure. transanal approach for rectal excision offers new insights into the complex pelvic and perineal neuroanatomy while the procedure itself remains a challenge for surgeons. Preoperative anatomical planning and 3D reconstruction may help in anticipating technical difficulties, resulting in more precise surgical dissections and decreased postoperative complications.

Perirectal Fascial Anatomy: New Insights Into an Old Problem

BACKGROUND

The architecture of perirectal fasciae is complex as mirrored by different anatomical concepts.

OBJECTIVE

This study aimed to perform a comprehensive visualization of perirectal fasciae to facilitate strategies of rectal surgery such as total mesorectal excision, intersphincteric resection, and transanal total mesorectal excision.

DESIGN

Macroscopic dissection and histologic studies of perirectal fasciae and autonomic pelvic nerves were performed.

SETTINGS

This study was conducted in a university laboratory of macroscopic and microscopic anatomy.

PATIENTS

Thirteen (5 female) pelvic specimens were obtained from body donors (67-92 years of age).

MAIN OUTCOME MEASURES

The primary outcomes measured were the photodocumentation of perirectal fasciae, spaces and fusion zones, and histologic and immunohistochemical analysis of key structures.

RESULTS

The retrorectal space is a mesofascial interface between the mesorectal fascia and the parietal pelvic fascia. The parietal pelvic fascia is composed of 2 lamellae ensheathing the autonomic pelvic nerves. The outer lamella of the parietal pelvic fascia and the presacral fascia confine the presacral space. The presacral fascia covers the median sacral blood vessels. Approximately at the fourth sacral vertebra, all fascial layers fuse in the midline and are densely connected to the posterior rectal wall via the rectosacral ligament. The parietal pelvic fascia fuses with the pubococcygeal and longitudinal rectal muscles at the anorectal junction. Anterolaterally, the neurovascular bundles are closely related to this fascial fusion zone and the rectogenital septum.

LIMITATIONS

Because of the increased age of the body donors, the findings may be subjected to age-related degenerative processes.

CONCLUSIONS

The 2 lamellae of the parietal pelvic fascia and the fascial fusion zones are key structures of perirectal anatomy. For autonomic nerve preservation, the recognition of the inner lamella of the parietal pelvic fascia is crucial. To avoid inadvertent rectal perforation or accidental presacral dissection, the rectosacral ligament must be identified and transected for complete rectal mobilization. See Video Abstract at http://links.lww.com/DCR/B389. ANATOMÍA FASCIAL PERIRRECTAL: NUEVOS CONCEPTOS SOBRE UN ANTIGUO PROBLEMA: La arquitectura de las fascias perirrectales es compleja, reflejada por distintos conceptos anatómicos.Integración de conceptos sobre las fascias perirrectales para facilitar las estrategias de cirugía rectal, como la escisión mesorrectal total, la resección interesfintérica y la escisión mesorrectal total transanal.Disección macroscópica y estudios histológicos de fascias perirrectales y nervios pélvicos autonómicos.Laboratorio universitario de anatomía macroscópica y microscópica.Trece (5 mujeres) muestras pélvicas obtenidas de donantes de cuerpo (67-92 años).Foto documentación de fascias perirrectales, espacios y zonas de fusión, análisis histológico e inmunohistoquímico de estructuras claves.El espacio retrorectal es una interfaz mesofascial entre la fascia mesorrectal y la fascia pélvica parietal. Este último se compone de dos láminas que envuelven los nervios pélvicos autonómicos. La lámina externa de la fascia pélvica parietal y la fascia presacra definen el espacio presacro. La fascia presacra cubre los vasos sanguíneos sacros medianos. Aproximadamente en la cuarta vértebra sacra, todas las capas fasciales se unen en la línea media y están densamente conectadas a la pared rectal posterior a través del ligamento rectosacro. La fascia pélvica parietal se une con los músculos rectal pubococcígeo y longitudinal en la unión anorrectal. Anterolateralmente, los haces neurovasculares están estrechamente relacionados con esta zona de fusión fascial y el tabique rectogenital.Debido al aumento de la edad de los donantes de cuerpos, los hallazgos pueden estar sujetos a procesos degenerativos relacionados con la edad.Las dos láminas de la fascia pélvica parietal y las zonas de fusión fascial son estructuras claves de la anatomía perirrectal. Para la preservación del nervio autónomo de nervios pélvicos autonómicos, el reconocimiento de la lámina interna de la fascia pélvica parietal es importante. Para evitar la perforación rectal inadvertida o la disección presacra accidental, el ligamento rectosacro debe ser identificado y seccionado para una movilización rectal completa. Consulte Video Resumen en http://links.lww.com/DCR/B389.

Gastrointestinal stromal tumor of the rectum resected by transanal total mesorectal excision after neoadjuvant imatinib treatment: A case report

This report describes the combination of a transanal total mesorectal excision (TaTME) and neoadjuvant therapy with Imatinib mesylate (IM) for a gastrointestinal stromal tumor (GIST) of the lower rectum. A 49-year-old man presented with a submucosal tumor with ulcer located 3 cm above the anal verge. Histopathologically, a biopsy showed spindle-shape cells, positive for C-kit and CD34, negative for smooth muscle actin, desmin and S-100 protein. Genetically, this GIST had the mutation in KIT exon 11. IM (400 mg/d) was administered as neoadjuvant therapy for 80 days. The GIST shrank from 4.7 to 3.3 cm in diameter. Abdominal and transanal approach were started at the same time. The tumor was resected by TaTME successfully. The manometric pressure data and anal function were preserved before and after surgery. TaTME and neoadjuvant therapy with IM provide a treatment option which can preserve anal function for the lower rectal GIST.

Future Directions

Transanal total mesorectal excision (taTME) is a novel technique that has evolved over the years to address the challenges of low rectal cancer surgery by applying the principles and benefits of laparoscopic surgery to more historic transanal techniques. It has been popularized through its use in rectal cancer, but the transanal approach is slowly being expanded to tackle different clinical scenarios including benign conditions such as inflammatory bowel disease and endometriosis. For all of these new indications, it is the desire to access and begin the dissection in native tissue beyond the pathology which makes this approach applicable to other diseases where anatomy can be challenging. Training pathways to safely introduce taTME in a standardized manner are being developed and implemented in a bid to ensure adequate training to all the surgeons using this technique and thus minimize complications and patient morbidity. The future directions of this promising technique include the use of image and optical technological enhancement to aid navigation, the use of pneumorectum stabilization, and perhaps the use of fluorescence as a safety improvement. Developments have come also from the field of robotics. After a demonstration of feasibility in cadaver models, a growing experience has been gathered in the robotic approach to taTME, covered in the last part of this chapter.

Are We Underdiagnosing Hirschsprung Disease?

Hirschsprung disease (HSCR) is conventionally defined as aganglionosis of the distal rectum and a variable length of proximal contiguous bowel with a transition zone of ganglionic, but neuroanatomically abnormal, bowel located immediately upstream. Recent improvement in our understanding of the pathology and genetics of HSCR and relevant animal models indicates highly variable expressivity. The spectrum of intestinal neuropathology includes patients with very short-segment aganglionosis, limited to the distal 1 to 2 cm of the rectum, and possibly patients with no true aganglionic segment, but nonphysiological transition zone pathology in their distal rectums. The presence or absence of submucosal ganglion cells in a rectal biopsy is not sufficient to exclude these patients, in whom submucosal nerve hypertrophy and/or abnormal cholinergic mucosal innervation may be the only diagnostic clues. In addition, diagnosis or exclusion of HSCR by rectal biopsy now relies in part on mucosal patterns of calretinin immunohistochemistry, with less emphasis on submucosal tissue adequacy and assessment of cholinergic innervation. These recent trends in the surgical pathology approach to rectal biopsies may miss patients at the phenotypically milder end of the malformation spectrum, with profound implications for subsequent management, prognosis, and genetic counseling.

[Transanal total mesorectal excision-a critical appraisal]

INTRODUCTION

Total mesorectal excision (TME) is the international standard for rectal cancer surgery. In addition to laparoscopic TME (lapTME), transanal TME (taTME) was developed in recent years to reduce the rate of incomplete TME, conversion to open surgery and postoperative functional impairment. Despite limited evidence, this technique is becoming increasingly more popular and is already routinely used by many hospitals for rectal cancer in varying tumor level locations. The aim of this review was to evaluate the taTME compared to anterior rectal resection with lapTME as the standard of care in rectal cancer surgery based on currently available evidence.

METHOD

The databases PubMed and Medline were systematically searched for publications on transanal total mesorectal excision (taTME) and transanal minimally invasive surgery (TAMIS). Relevant studies were selected and further research based on the reference lists was undertaken.

RESULTS

A total of 16 studies analyzing 3782 patients were identified. The taTME does not lead to a higher rate of complete TME-resected specimens compared to the standard procedure. So far, superiority could not be demonstrated for complication rates or for functional or oncological results. Serious complications secondary to dissection in incorrect planes were observed. The anastomotic level generally seems to be closer to the sphincter after taTME versus anterior lapTME.

CONCLUSION

Considering current evidence, taTME failed to show superiority compared to conventional anterior lapTME. Although taTME has some potential advantages, it carries substantial risks. If performed outside of clinical trials, it should therefore only be used in carefully selected patients with a high possibility of conversion, following adequate patient informed consent and after intense and systematic training of the surgeon.

Anastomotic leak after transanal total mesorectal excision: grading of severity and management aimed at preservation of the anastomosis

AIM

The transanal approach to total mesorectal excision (TaTME) as an alternative to conventional anterior resection offers an improved view to otherwise restricted anatomical regions in obese and narrow male pelves and unfavourable tumour locations. Guidelines for the management of anastomotic leakage (AL) following low rectal resections are scarce.

PATIENTS AND METHODS

Prospectively collected data of all consecutive patients undergoing TaTME between December 2014 and April 2017 in our centre were analysed retrospectively. Existing classification systems for AL were modified with regard to transanal anastomotic-preserving management.

RESULTS

TaTME was performed in 66 patients with a median age of 56.2 years. The overall incidence of AL was 12.1% (n = 8). AL grading was differentiated in Grades I to V according to the severity of necrosis and abscess development. Two patients suffered from AL Grade II, one patient from Grade III, three patients from Grade IV and two patients from Grade V. Preservation of the anastomosis following AL was achieved by the damage control concept in six of eight patients (75%) with a median duration of hospital stay of 36 days. Two patients received a Hartmann procedure (Grades IV and V).

CONCLUSION

Our study demonstrates that management of AL following TaTME is challenging but definitely amenable to strategies aimed at preserving the anastomosis by appropriate damage control. The modified classification system might serve as guidance for anastomosis-preserving management.

To what extent is the low anterior resection syndrome (LARS) associated with quality of life as measured using the EORTC C30 and CR38 quality of life questionnaires?

PURPOSE

Treatment of rectal cancer often results in disturbed anorectal function, which can be quantified by the Low Anterior Resection Syndrome (LARS) score. This study investigates the association of impaired anorectal function as measured with the LARS score with quality of life (QoL) as measured with the EORTC-QLQ-C30 and CR38 questionnaires.

METHODS

All stoma-free patients who had undergone sphincter-preserving surgery for rectal cancer from 2000 to 2014 in our institution were retrieved from a prospective database. They were contacted by mail and asked to return the questionnaires. QoL was evaluated in relation to LARS and further patient- and treatment factors using univariate and multivariate analysis.

RESULTS

Of the eligible patients (n = 331), 261 (78.8%) responded with a complete LARS score. Mean score for global QoL according to the EORTC-QLQ-C30 questionnaire was 63 ± 21 for all patients. If major LARS was present, mean score decreased to 56 ± 19 in contrast to 67 ± 20 in patients with no/minor LARS (p < 0.001). In regression analysis, major LARS was furthermore associated with reduced physical, role, emotional, cognitive and social functioning as well as impaired body image, more micturition problems and poorer future perspective. It was not related to sexual function. The variance explained by major LARS in the differences of QoL was approximately 10%.

CONCLUSION

The presence of major LARS after rectal resection for cancer is negatively associated with global health as well as many other aspects of QoL. Preserving anorectal function and treatment of LARS are potential measures to improve QoL in this patient group.

Short- and long-term outcomes of transanal versus laparoscopic total mesorectal excision for mid-to-low rectal cancer: a meta-analysis

BACKGROUND AND OBJECTIVES

Transanal total mesorectal excision (TaTME) is positioned at the cutting edge of minimally invasive approach to mid- and low rectal cancer. This meta-analysis was to compare the short- and long-term outcomes of TaTME versus laparoscopic total mesorectal excision (LTME) and to evaluate the safety, efficacy, and possible superiority of TaTME.

METHODS

A comprehensive search was conducted for randomized controlled trials (RCTs) and non-RCTs (NRCTs) comparing TaTME with LTME. Inter-group differences were evaluated via standardized mean differences and relative risks (RRs). All outcomes were analyzed using fixed effects or random effects models according to the heterogeneity. Statistical analysis was performed using Stata/SE 12.0 software.

RESULTS

Eleven studies (1 RCT and 10 NRCTs) with involving 757 patients were included. Among which, 361 patients underwent TaTME and 396 patients underwent LTME. Comparing the surgical and oncological quality of resection of TaTME with that of LTME, reports of TaTME indicated favorable outcomes considering mesorectal resection quality, circumferential resection margin involvement, intraoperative blood loss, conversions, and postoperative complications, while the differences between the two groups had no statistical significance in terms of distal resection margin, harvested lymph node, operation time, hospital stay, recurrence, 2-year overall survival (OS), and 2-year disease-free survival.

CONCLUSION

TaTME is a promising surgical technique and is fully a safe, efficacious, and diffusible alternative to LTME in managing mid- and distal rectal cancer. Larger scale, national, multicentric RCTs are warranted to further verify these results and the possible superiority of TaTME.

Internal anal sphincter nerves - a macroanatomical and microscopic description of the extrinsic autonomic nerve supply of the internal anal sphincter

AIM

The internal anal sphincter (IAS) contributes substantially to anorectal functions. While its autonomic nerve supply has been studied at the microscopic level, little information is available concerning the macroscopic topography of extrinsic nerve fibres. This study was designed to identify neural connections between the pelvic plexus and the IAS, provide a detailed topographical description, and give histological proof of autonomic nerve tissue.

METHODS

Macroscopic dissection of pelvic autonomic nerves was performed under magnification in seven (five male, two female) hemipelvises obtained from body donors (67-92 years). Candidate structures were investigated by histological and immunohistochemical staining protocols to visualize nerve tissue.

RESULTS

Nerve fibres could be traced from the anteroinferior edge of the pelvic plexus to the anorectal junction running along the neurovascular bundle anterolaterally to the rectum and posterolaterally to the prostate/vagina. Nerve fibres penetrated the longitudinal rectal muscle layer just above the fusion with the levator ani muscle (conjoint longitudinal muscle) and entered the intersphincteric space to reach the IAS. Histological and immunohistochemical findings confirmed the presence of nerve tissue.

CONCLUSIONS

Autonomic nerve fibres supplying the IAS emerge from the pelvic plexus and are distinct to nerves entering the rectum via the lateral pedicles. Thus, they should be classified as IAS nerves. The identification and precise topographical location described provides a basis for nerve-sparing rectal resection procedures and helps to prevent postoperative functional anorectal disorders.

Long-term outcomes by a transanal approach to total mesorectal excision for rectal cancer

BACKGROUND

The challenge of performing a good total mesorectal excision (TME) dissection, particularly in the distal 1/3 of the rectum, has spurred interest in new techniques. Robotic surgery is advocated by some, and more recently, a "new" approach, the transanal total mesorectal excision, has been popularized to address this problem. While great interest in this technique exists, little long-term outcome data are available. We have been utilizing a transanal abdominal transanal approach to TME in order to facilitate the distal dissection, and here, we provide our long-term outcomes using this approach in the management of rectal cancer.

METHODS

From a prospectively maintained rectal cancer database, we identified 373 consecutive rectal cancers treated with sphincter preservation surgery through a combined transanal and abdominal approach to TME. Perioperative, pathological, and oncologic outcomes were analyzed.

RESULTS

Three hundred and seventy-three patients with rectal cancer underwent a transanally initiated TME with mean follow-up of 5.5 years. 91% of cancers were in the distal rectum. 68.9% were men and 53.2% of cancers were tethered or fixed on presentation. 97.7% received neoadjuvant radiotherapy (mean 5405 cGy, 5-fluorouracil based); average time from completion of neoadjuvant therapy to surgery was 11 weeks. 180 and 193 patients underwent completion of their operation through open and laparoscopic abdominal approaches. 96% of TME specimens were complete/near complete, 94% had a negative circumferential resection margin, and 98.6% had a negative distal margin. Perioperative morbidity and mortality rates were 13.4 and 0.3%. Overall local recurrence (LR), DM, and Kaplan-Meier 5-year actuarial survival were 7.4, 19.5, and 90%, respectively.

CONCLUSION

This is the first report of long-term data using a transanal approach to TME supporting this approach for rectal cancer. Our data with 5-year follow-up show that adequate distal and circumferential margins with very good-quality TME specimens, and a low risk for LR with excellent overall survival can be achieved using this technique. Our long-term results support the promising reports of early experiences in the literature.

A multicentre randomised controlled trial to evaluate the efficacy, morbidity and functional outcome of endoscopic transanal proctectomy versus laparoscopic proctectomy for low-lying rectal cancer (ETAP-GRECCAR 11 TRIAL): rationale and design

BACKGROUND

Total mesorectal excision is the standard surgical treatment for mid- and low-rectal cancer. Laparoscopy represents a clear leap forward in the management of rectal cancer patients, offering significant improvements in post-operative measures such as pain, first bowel movement, and hospital length of stay. However, there are still some limits to its applications, especially in difficult cases. Such cases may entail either conversion to an open procedure or positive resection margins. Transanal endoscopic proctectomy (ETAP) was recently described and could address the difficulties of approaching the lower third of the rectum. Early series and case-control studies have shown favourable short-term results, such as a low conversion rate, reduced hospital length of stay and oncological outcomes comparable to laparoscopic surgery. The aim of the proposed study is to compare the rate of positive resection margins (R1 resection) with ETAP versus laparoscopic proctectomy (LAP), with patients randomly assigned to each arm.

METHODS/DESIGN

The proposed study is a multicentre randomised trial using two parallel groups to compare ETAP and LAP. Patients with T3 lower-third rectal adenocarcinomas for whom conservative surgery with manual coloanal anastomosis is planned will be recruited. Randomisation will be performed immediately prior to surgery after ensuring that the patient meets the inclusion criteria and completing the baseline functional and quality of life tests. The study is designed as a non-inferiority trial with a main criterion of R0/R1 resection. Secondary endpoints will include the conversion rate, the minimal invasiveness of the abdominal approach, postoperative morbidity, the length of hospital stay, mesorectal macroscopic assessment, functional urologic and sexual results, faecal continence, global quality of life, stoma-free survival, and disease-free survival at 3 years. The inclusion period will be 3 years, and every patient will be followed for 3 years. The number of patients needed is 226.

DISCUSSION

There is a strong need for optimal evaluation of the ETAP because of substancial changes in the operative technique. Assessment of oncological safety and septic risk, as well as digestive and urological functional results, is particularily mandatory. Moreover, benefits of the ETAP technique could be demonstrated  in post-operative outcome.

TRIAL REGISTRATION

ClinicalTrial.gov: NCT02584985 . Date and version identifier: Version n°2 - 2015 July 6.

[Hybrid TAMIS total mesorectal excision. A new perspective in treatment of distal rectal cancer - Technique and results]

BACKGROUND

Transanal minimally invasive surgery (TAMIS) represents a promising technique for total mesorectal excision (TME) with respect to radicalness and preservation of function. There are only few publications in the literature describing results in patients with distal rectal cancer.

METHODS

Between May 2013 and March 2015, 24 selected patients with a rectal carcinoma < 6 cm from the anal verge underwent a laparoscopically assisted TAMIS TME (Hybrid-TAMIS TME) procedure. This prospective observational study was conducted to examine the safety of the technique and the quality of TME surgery in distal rectal cancer and to assess the short-term postoperative outcome.

RESULTS

The median age of patients (18 male and 6 female) at the time of surgery was 57 years (range 35-77 years) and 7 patients (29 %) had a body mass index (BMI) > 30 kg/m(2). Specimen excision was carried out transanally in 19 patients. Pathological grading of TME specimens was good in 22 (92 %) and moderate in 2 cases. After neoadjuvant radiochemotherapy a complete pathological remission was identified in five patients. The median distal resection margin was 7 mm (range 2-30 mm), the median circumferential resection margin was 6 mm (range <1 mm-30 mm) and in 2 patients the tumor was ≤ 1 mm from the positive circumferential margin. A colonic reservoir was created in 19 patients (79 %) and no 30-day mortalities occurred. Morbidity was 29 %, including 1 anastomotic leak, 2 hematomas and 1 neurogenic bladder.

CONCLUSION

Hybrid-TAMIS TME for distal rectal cancer is safe and can provide a sphincter-preserving high-quality TME in difficult cases. Studies with long-term follow-up assessing oncological and functional results are mandatory.

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

BACKGROUND

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.

STUDY DESIGN

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.

RESULTS

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.

CONCLUSIONS

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.

Surgeons' assessment of internal anal sphincter nerve supply during TaTME - inbetween expectations and reality

Background: Intraoperative identification of nerve fibers heading from the inferior rectal plexus (IRP) to the internal anal sphincter (IAS) is challenging. The transanal total mesorectal excision (TaTME) is said to better preserve pelvic autonomic nerves. The aim of this study was to investigate the nerve identification rates during TaTME by transanal visual and electrophysiological assessment.

Material and methods: A total of 52 patients underwent TaTME for malignant conditions. The IRP with its posterior branches to the IAS and the pelvic splanchnic nerves (PSN) were visually assessed in 20 patients (v-TaTME). Electrophysiological nerve identification was performed in 32 patients using electric stimulation under processed electromyography of IAS (e-TaTME).

Results: The indication profile for TaTME was comparable between the v-TaTME and the e-TaTME group. The identification of IRP was more meaningful under electrophysiological assessment than under visual assessment for the left pelvic side (81% vs. 45%, p = 0.008) as well as the right pelvic side (78% vs. 45%, p = 0.016). The identification rates for PSN did not significantly differ between both groups, respectively (81% vs. 75%, p = 0.420 and 84% vs. 70%, p = 0.187).

Conclusions: The transanal approach facilitated visual identification of IAS nerve supply. In combination with electrophysiological nerve assessment the identification rate almost doubled. For further insights functional data are needed.

Transanal total mesorectal excision: Towards standardization of technique

AIM: To describe the role of Transanal total mesorectal excision (TaTME) in minimally invasive rectal cancer surgery, to examine the differences in patient selection and in reported surgical techniques and their impacts on postoperative outcomes and to discuss the future of TaTME.

METHODS: MEDLINE (PubMed), EMBASE, and The Cochrane Library were systematically searched through the 1^st of March 2015 using a predefined search strategy.

RESULTS: A total of 20 studies with 323 patients were included. Most studies were single-arm prospective studies with fewer than 100 patients. Multiple transanal access platforms were used, and the laparoscopic approach was either multi- or single port. The procedure was initiated transanally or transabdominally. If a simultaneous approach with 2 operating surgeons was chosen, the operative time was significantly reduced.

CONCLUSION: TaTME was also associated with better TME specimens and a longer distal resection margin. TaTME is thus feasible in expert hands, but the learning curve and safety profile are not well defined. Long-term follow-up regarding anal function and oncological outcomes should be performed in the future.