Transanal endoscopic microsurgery in rectal adenomas: experience of six Italian centres

Transanal endoscopic microsurgical submucosal dissection (TEM-ESD) for rectal adenomas: a retrospective cohort study of 145 consecutive cases

PURPOSE

Transanal endoscopic microsurgery (TEM) and endoscopic submucosal dissection (ESD) are currently the two most popular methods for resecting large rectal adenomas en bloc. However, damage to the mesorectum in the case of TEM, plus the technical challenges and long procedure times of flexible ESD, are major disadvantages of these procedures. Transanal endoscopic microsurgical submucosal dissection (TEM-ESD) is a new technique, combining the ergonomic features of TEM with the minimally invasive approach of ESD. The aim of our study was to assess the feasibility and safety of TEM-ESD for resection of large rectal adenomas.

METHODS

We retrospectively analyzed all TEM-ESD procedures performed in Karlsruhe Municipal Hospital between 2012 and 2019, isolated all cases of adenomas, and analyzed the perioperative and follow-up data of the patients.

RESULTS

We identified 145 cases matching our criteria. The median size of the lesions was 4.2 cm, and the median operating time was 45 min. The en bloc resection rate was 100%, and the complete en bloc resection rate was 78.6%. The overall morbidity rate was 6.9%. In a median follow-up period of 24 months, there was a local recurrence in 4.8% of the cases.

CONCLUSIONS

TEM-ESD is a safe and feasible therapeutic option for resecting large rectal adenomas, offering high en bloc resection and low recurrence rates combined with short operating time and low morbidity. TRIAL REGISTRATION NUMBER (CLINICALTRIALS.GOV): NCT04870931.

[Transanal endoscopic rectal resection: immediate and long-term results]

OBJECTIVE

To analyze the results of transanal endoscopic microsurgery in patients with rectal tumors.

MATERIAL AND METHODS

We analyzed 87 transanal endoscopic resections of rectal benign tumors (35 patients) and rectal cancer cT1N0M0 (52 patients) for the period since 2012.

RESULTS

There were 2 (3.8%) intraoperative intestinal wall perforations into abdominal cavity and 2 (3.8%) postoperative bleedings among patients with rectal cancer. Four (7.7%) patients developed recurrent rectal cancer (pT1N0M0 - 1 patient, pT2N0M0 - 3 patients; by tumor grades: G1 - 2 patients, G2 - 2 patients) within 1.6-5.2 years. All recurrent tumors were located on anterior rectal wall. In patients with rectal cancer, cumulative relapse-free survival was 0.923 (standard error 0.037), cumulative overall survival - 0.926 (standard error 0.043). There was 1 (4.3%) intraoperative intestinal wall perforation among patients with benign rectal tumors. Postoperative anastomotic leakage occurred in 1 (4.3%) patient. Recurrent benign tumors occurred in 2 (8.7%) patients with villous rectal tumors. No relapses were observed in patients with rectal adenomas (p=1.0).

CONCLUSION

Transanal endoscopic rectal resection is effective for benign rectal tumors and rectal cancer pT1N0M0 with high relapse-free and overall survival and low complication rate. Risk factors of recurrence are tumor stage pT2N0M0, tumor location on anterior wall and distance from the anus over 10 cm.

Transanal endoscopic microsurgical submucosal dissection: Are there advantages over conventional ESD?

INTRODUCTION

Transanal endoscopic microsurgical submucosal dissection (TEM-ESD) is a technique that has been recently described for the treatment of large rectal adenomas and early rectal cancer. The purpose of our study is to compare TEM-ESD with flexible endoscopic submucosal dissection (ESD) in an experimental, ex vivo porcine model.

MATERIAL AND METHODS

We used TEM-ESD and flexible ESD to resect a total of 100 standardized 4 × 4cm lesions in an ex vivo porcine stomach model, performing 50 resections with each technique. Total procedure time, en bloc resection rate, injuries of the muscularis propria, perforation rate and learning curve were analysed.

RESULTS

TEM-ESD was associated with a significantly shorter total procedure time in comparison to ESD (19 min vs. 33 min, p < .001). The rates of en bloc resection, injury of the muscularis propria layer, and perforation were the same in both groups. The learning curve of TEM-ESD was shallower than that of ESD.

CONCLUSION

TEM-ESD showed an advantage over ESD in terms of procedure time and learning curve, with similar en bloc resection rates and safety profile in our experimental model.

Transanal endoscopic microsurgery for rectal villous tumours: Can we rely solely on preoperative biopsies and the surgeon’s experience?

Background

Transanal endoscopic microsurgery has become the standard of treatment for rectal villous adenomas. However, the role of preoperative imaging for these lesions is not clear. The aim of this study was to compare the value of preoperative imaging and surgeon clinical staging in the preoperative evaluation of patients with rectal villous adenomas having transanal endoscopic microsurgery resection.

Methods

We conducted a single-centre comparative retrospective cohort study of patients who underwent transanal endoscopic microsurgery surgery for rectal villous adenomas from 2011 to 2013. The intervention was preoperative imaging versus surgeon clinical staging. The primary outcome was the accuracy of clinical staging by preoperative imaging and surgeon clinical staging according to the histopathologic staging.

Results

A total of 146 patients underwent transanal endoscopic microsurgery surgery for rectal villous adenomas. One hundred and twelve (76.7%) of those patients had no preoperative imaging while 34 patients (23.3%) had either endorectal ultrasound (22 patients) or magnetic resonance imaging (12 patients). Surgeon staging was accurate in 89.3% of cases whereas staging by endorectal ultrasound was accurate in 40.9% cases and magnetic resonance imaging was accurate in 0% of cases. In the imaging group, inaccurate staging would have led to unnecessary radical surgery in 44.0% of patients.

Conclusion

This study was subject to selection bias because of its retrospective nature and the limited number of patients with imaging. Patients with rectal villous tumours without invasive carcinoma on biopsies and without malignant characteristics on appearance in the judgment of an experienced colorectal surgeon might not benefit from preoperative imaging before undergoing transanal endoscopic microsurgery procedures.

Transanal endoscopic microsurgery for rectal lesions in a specialist regional early rectal cancer centre: the Mersey experience

AIM

Organ-preserving local excision by transanal endoscopic microsurgery (TEM) for early rectal cancer offers significantly lower morbidity as compared to formal rectal cancer resection with acceptable outcomes. This study presents our 6-year experience of TEM for rectal lesions referred to a specialist early rectal cancer centre in the UK.

METHOD

Data were collected for all patients referred for TEM of suspected early rectal cancer to a regional specialist early rectal cancer multidisciplinary team (MDT) over a 6-year period.

RESULTS

One hundred and forty-one patients who underwent full-thickness TEM for suspected or confirmed early rectal cancer were included. Thirty patients were referred for TEM following incomplete endoscopic polypectomy. Final pathology was benign in 77 (54.6%) cases and malignant in 64 (45.4%). Of the 61 confirmed adenocarcinomas, TEM resections were pT0 in 17 (27.9%), pT1 in 32 (51.7%), pT2 in 11 (18.0%) and pT3 in 1 (1.6%). Thirty-eight of 61 patients (62.3%) had one or more poor histological prognostic features and these patients were offered further treatment. Twenty-three of 61 (37.7%) patients with rectal adenocarcinoma required no further treatment following TEM. Forty-three cases of rectal adenocarcinoma were available for establishing recurrence rates. Two of 43 patients (4.7%) developed a recurrence at a median follow-up of 28.7 months (12.1-66.5 months). The overall estimated 5-year overall survival rate was 87.9% and the disease-free survival rate was 82.9%.

CONCLUSION

Acceptable outcomes are possible for TEM surgery with appropriate patient selection, effective technique, expert histopathology, appropriate referral for adjuvant treatment and meticulous follow-up. This can be achieved through an early rectal cancer MDT in a dedicated specialist regional centre.

Assessing the safety and outcomes of repeat transanal endoscopic microsurgery

BACKGROUND

Transanal endoscopic microsurgery (TEM) is the treatment of choice for benign rectal tumors and select early rectal cancers. This surgical approach has become ubiquitous and surgeons are seeing recurrent lesions after TEM resection. This study aims to outline the safety and outcomes of repeat TEM when compared to primary TEM procedures.

METHODS

At St. Paul's Hospital, demographic, surgical, pathologic, and follow-up data for patients treated by TEM are maintained in a prospectively populated database. Two groups were established for comparison: patients undergoing first TEM procedure (TEM-P) and patients undergoing repeat TEM procedure (TEM-R).

RESULTS

Between 2007 and 2017, 669 patients had their first TEM procedure. Over this time frame, 57 of these patients required repeat TEM procedures, including 15 of these patients treated by 3 or more TEMs. Indications for repeat TEM included recurrence (78%), positive margins (15%), and metachronous lesions (7%). There were no differences between the groups in patient age, gender, or tumor histology. Compared to TEM-P, TEM-R had shorter operative times (38 vs. 52 min, p < 0.001), more distal lesions (5 vs. 7 cm, p < 0.004), and smaller lesions (3 vs. 4 cm, p < 0.0003). The TEM-R group had similar length of hospital stay (0.45 vs. 0.56 days, p = 0.65), rates of clear margins on pathology (81% vs. 88%, p = 0.09), and 30-day readmission rates (7% vs. 4%, p = 0.27) when compared to TEM-P group. TEM-R was more likely to be managed without suturing the surgical defect (72% vs. 32%, p < 0.0001). Repeat TEM was associated with similar post-operative complications as primary TEM graded on the Clavien-Dindo classification scale (Grade 1: 5% vs. 5%, Grade 2: 5% vs. 4%, Grade 3: 5% vs. 1%, p = 0.53). No 30-day mortality occurred in either group.

CONCLUSIONS

The St. Paul's Hospital TEM experience suggests repeat TEM is a safe and feasible procedure with similar outcomes as patients undergoing first TEM.

Is Previous Transanal Endoscopic Microsurgery for Early Rectal Cancer a Risk Factor of Worse Outcome following Salvage Surgery A Case-Matched Analysis

Introduction

Transanal endoscopic microsurgery (TEM) is a minimally invasive procedure which allows local excision of early-stage rectal cancer and can be used as an alternative treatment to radical surgery. Patients can undergo salvage total mesorectal excision (sTME) following TEM after finding of unfavourable histological features. This study aimed to compare results and possible complications of sTME following TEM and primary TME (pTME) procedures.

Methods

Between 2010 and 2017, early sTME was performed in 9 patients at the National Cancer Institute in Vilnius, Lithuania. These patients were compared with 18 patients who underwent pTME, matched according to gender, age, cancer stage, and operative procedure. Data were obtained from the patients' charts and reviewed prospectively. We recorded the demographics, tumour specifications, treatment, operation time, postoperative results complications, and oncological outcome. Fisher's exact test and student's T test was used to compare both groups.

Results

A total of 130 patients underwent TEM at our institution during the study period, of which 9 (6.92%) had to undergo sTME. The average age of the patients was 62.7 ± 7.07 years; 44.4% of the patients were male and 55.6% female. The average tumour size in the sTME group was 2.8 ± 1.05 cm (range 1.5-5) and 2.61 ± 1.36 cm (range 1-5) in the pTME group (p = 0.696). When comparing postoperative complications, statistically significant results were not found in either of the groups (p = 0.55). Operation time of pTME was significantly shorter on average, i.e. 43 min, compared to sTME (p < 0.0267). The average number of harvested lymph nodes was 12.44 ± 7.126 in the sTME and 12.5 ± 8.06 in the pTME group (p = 0.986). The circumferential resection margin (CRM) was negative in 92.6% (25/27) of specimens, while the CRM was positive in 2 cases (7.4%), both of which were from the sTME group. The average follow-up time was 22.8 months (8-80 months) for patients undergoing sTME and 19.33 months (2-88 months) for patients after pTME (p = 0.71).

Conclusions

TEM is a relatively safe method for treating patients with early rectal cancer without high-risk features. It can be used in exceptional cases with high-risk features when the patient is not fit for radical surgery.

Transanal Endoscopic Microsurgery for Patients With Rectal Tumors: A Single Institution's Experience

PURPOSE

The purpose of this study was to look at our complication rates and recurrence rates, as well as the need for further radical surgery, in treating patients with benign and early malignant rectal tumors by using transanal endoscopic microsurgery (TEM).

METHODS

Our study included 130 patients who had undergone TEM for rectal adenomas and early rectal cancer from December 2009 to December 2015 at the Department of Surgical Oncology, National Cancer Institute, Lithuania. Patients underwent digital and endoscopic evaluation with multiple biopsies. For preoperative staging, pelvic magnetic resonance imaging or endorectal ultrasound was performed. We recorded the demographics, operative details, final pathologies, postoperative lengths of hospital stay, postoperative complications, and recurrences.

RESULTS

The average tumor size was 2.8 ± 1.5 cm (range, 0.5-8.3 cm). 102 benign (78.5%) and 28 malignant tumors (21.5%) were removed. Of the latter, 23 (82.1%) were pT1 cancers and 5 (17.9%) pT2 cancers. Of the 5 patients with pT2 cancer, 2 underwent adjuvant chemoradiotherapy, 1 underwent an abdominoperineal resection, 1 refused further treatment and 1 was lost to follow up. No intraoperative complications occurred. In 7 patients (5.4%), postoperative complications were observed: urinary retention (4 patients, 3.1%), postoperative hemorrhage (2 patients, 1.5%), and wound dehiscence (1 patient, 0.8%). All complications were treated conservatively. The mean postoperative hospital stay was 2.3 days.

CONCLUSION

TEM in our experience demonstrated low complication and recurrence rates. This technique is recommended for treating patients with a rectal adenoma and early rectal cancer and has good prognosis.

Transanal endoscopic surgery: past, present and future

Transanal endoscopic surgery is a safe, established technique to remove lesions in the rectum via the anus. This article reviews its evolution, approaches, indications and evidence for its role in treating benign rectal polyps. The future of transanal endoscopic surgery in rectal cancer and inflammatory bowel disease is also explored.

Transanal endoscopic microsurgery for rectal adenomas: single center experience

INTRODUCTION

Transanal endoscopic microsurgery (TEM) is a method of choice for the local treatment of rectal adenomas. Though generally considered as a safe method, some authors have expressed skepticism about the anorectal function following TEM.

AIM

To review our experience in using TEM for removal of rectal adenomas. We focused on morbidity, local recurrence rates, and anorectal function following the operation.

MATERIAL AND METHODS

The study included 72 patients who underwent TEM for rectal adenomas from December 2009 to November 2014 at the Department of Surgical Oncology, National Cancer Institute. Of the 72 patients, 31 (43.1%) were lost in the follow-up. We recorded the demographics, operative details, final pathology, post-operative length of stay, post-operative complications, recurrences and functional outcome for each of the 41 (56.9%) remaining participants.

RESULTS

Of the 41 eligible patients, 19 (46.3%) were male and 22 (53.7%) were female. The mean age of our patients was 66.8 years. There were no intraoperative complications. In 4 (9.8%) cases, postoperative complications were observed - urinary retention (2 cases, 4.9%) and postoperative hemorrhage (2 cases, 4.9%). All complications were treated conservatively. There was a single case (2.4%) of adenoma recurrence during the follow-up period. The mean score of the FISI questionnaire was 7.6 ±9.2 (ranging from 0 to 36), and the mean Wexner score was 2.3 ±3.4 (ranging from 0 to 17).

CONCLUSIONS

Transanal endoscopic microsurgery in our experience demonstrated low complication and recurrence rates, and good functional results. We conclude that TEM is an effective and safe method for the treatment of rectal adenomas.

Anorectal function and outcomes after transanal minimally invasive surgery for rectal tumors

BACKGROUND:

Transanal endoscopic microsurgery is a minimally invasive technique that allows full-thickness resection and suture closure of the defect for large rectal adenomas, selected low-risk rectal cancers, or small cancers in patients who have a high risk for major surgery. Our aim, in the given prospective study was to report our initial clinical experience with TAMIS, and to evaluate its effects on postoperative anorectal functions.

MATERIALS AND METHODS:

In 10 patients treated with TAMIS for benign and malignant rectal tumors, preoperative and postoperative anorectal function was evaluated with anorectal manometry and Cleveland Clinic Incontinence Score.

RESULTS:

The mean distance of the tumors from the anal verge was 5.6 cm, and mean tumor diameter was 2.6 cm. All resection margins were tumor free. There was no difference in preoperative and 3-week postoperative anorectalmanometry findings; only mean minimum rectal sensory volume was lower at 3 weeks after surgery. The Cleveland Clinic Incontinence Score was normal in all patients except one which resolved by 6 weeks after surgery.The mean postoperative follow-up was 28 weeks without any recurrences.

CONCLUSION:

Transanal minimally invasive surgery is a safe and effective procedure for treatment of rectal tumors and can be performed without impairing anorectal functions.

Impact of technology on indications and limitations for transanal surgical removal of rectal neoplasms

Transanal surgery has and continues to be well accepted for local excision of benign rectal disease not amenable to endoscopic resection. More recently, there has been increasing interest in applying transanal surgery to local resection of early malignant disease. In addition, some groups have started utilizing a transanal route in order to accomplish total mesorectal excision (TME) for more advanced rectal malignancies. We aim to review the role of various transanal and endoscopic techniques in the local resection of benign and malignant rectal disease based on published trial data. Preliminary data on the use of transanal platforms to accomplish TME will also be highlighted. For endoscopically unresectable rectal adenomas, transanal surgery remains a widely accepted method with minimal morbidity that avoids the downsides of a major abdomino-pelvic operation. Transanal endoscopic microsurgery and transanal minimally invasive surgery offer improved visualization and magnification, allowing for finer and more precise dissection of more proximal and larger rectal lesions without compromising patient outcome. Some studies have demonstrated efficacy in utilizing transanal platforms in the surgical management of early rectal malignancies in selected patients. There is an overall higher recurrence rate with transanal surgery with the concern that neither chemoradiation nor salvage surgery may compensate for previous approach and correct the inferior outcome. Application of transanal platforms to accomplish transanal TME in a natural orifice fashion are still in their infancy and currently should be considered experimental. The current data demonstrate that transanal surgery remains an excellent option in the surgical management of benign rectal disease. However, care should be used when selecting patients with malignant disease. The application of transanal platforms continues to evolve. While the new uses of transanal platforms in TME for more advanced rectal malignancy are exciting, it is important to remain cognizant and not sacrifice long term survival for short term decrease in morbidity and improved cosmesis.

[Is it radical enough? Transanal endoscopic microsurgery for the treatment of rectal neoplasia -- clinicopathological viewpoint]

The transanal endoscopic microsurgery (TEM) provides lower relapse and complication rate for the the surgical treatment of the neoplasms of the middle and lower third of the rectum in selected cases. Hence, it can be an alternative method of the conventional approaches, if it does not compromise oncological radicality. The TEM procedure has been started at the 1st Department of Surgery, Semmelweis University in the fall of 2013. In this short study we have evaluated the clinicopathological characteristics of patients undergoing TEM between September 2013 and September 2014. Fourty-four patients were included in our retrospective analysis. 12 patients had low grade adenoma, 14 patients had high grade adenoma, 17 patients had invasive adenocarcinoma, while one was operated for a neuroendocrine tumor. There was no difference in the size of neoplasms between the low and high grade adenomas or adenocarcinomas (p = 0.210), tumors below the size of 30 mm or over 30 mm displayed no significant difference either (p = 0.424). The surgical margins were free of tumor in 41 cases (95.3%). In 13 out of 44 cases the preoperative histology proposed a lower grade neoplasm than the final report (p < 0.001). These results demonstrate that the surgical treatment of large adenomas with TEM technique, which involves excision of the whole bowel wall, is more appropriate than the fractionated removal or polypectomy supplemented by mucosectomy. The pT2 stage tumours might be subjected to the TEM method in selected cases (e.g. following neoadjuvant treatment or palliative care), but this has to be confirmed with prospecively evaluated large series clinical studies which are currently ongoing.

Transanal endoscopic microsurgery: a review

Rectal adenomas and cancers occur frequently. Small adenomas can be removed colonoscopically, whereas larger polyps are removed via conventional transanal excision. Owing to technical difficulties, adenomas of the mid- and upper rectum require radical resection. Transanal endoscopic microsurgery (TEM) was first designed as an alternative treatment for these lesions. However, since its development TEM has been also used for a variety of rectal lesions, including carcinoids, rectal prolapse and diverticula, early stage carcinomas and palliative resection of rectal cancers. The objective of this review is to describe the current status of TEM in the treatment of rectal lesions. Since the 1980s, TEM has advanced substantially. With low recurrence rates, it is the method of choice for resection of endoscopically unresectable adenomas. Some studies have shown benefits to its use in treating early T1 rectal cancers compared with radical surgery in select patients. However, for more advanced rectal cancers TEM should be considered palliative or experimental. This technique has also been shown to be safe for the treatment of other uncommon rectal tumours, such as carcinoids. Transanal endoscopic microsurgery may allow for new strategies in the treatment of rectal pathology where technical limitations of transanal techniques have limited endoluminal surgical innovations.

Transanal endoscopic microsurgery

Transanal endoscopic microsurgery (TEMS) is a well established method of accurate resection of specimens from the rectum under binocular vision. This review examines its role in the treatment of benign conditions of the rectum and the evidence to support its use and compliment existing endoscopic treatments. The evolution of TEMS in early rectal cancer and the concepts and outcomes of how it has been utilised to treat patients so far are presented. The bespoke nature of early rectal cancer treatment is changing the standard algorithms of rectal cancer care. The future of TEMS in the organ preserving treatment of early rectal cancer is discussed and how as clinicians we are able to select the correct patients for neoadjuvant or radical treatments accurately. The role of radiotherapy and outcomes from combination treatment using TEMS are presented with suggestions for areas of future research.

Repeated transanal endoscopic microsurgery is feasible and safe

BACKGROUND

The benefits of transanal endoscopic microsurgery (TEM) for the excision of benign and low-grade malignant lesions in the low and middle rectum are well recognized. This study examined the feasibility and safety of a repeated TEM procedure.

PATIENTS AND METHODS

Patients who underwent a repeat TEM for excision of rectal lesions, either for involved resection margins or for local recurrence, between the years 2000 and 2010, were identified. Rectal lesion characteristics were retrieved. Mean operative times, length of hospital stay, and intra- and postoperative complications were compared between primary and repeated procedures. The postoperative histopathology reports were reviewed, and the adequacy of resection was determined. All patients completed a questionnaire based on the Wexner score for anal sphincter function evaluation.

RESULTS

Fourteen patients (3 female, 11 male) underwent a repeat TEM operation during the study period. All procedures were completed endoscopically. Indications for repeated TEM were involved margins in 12 patients and recurrence of benign tumor in 2. Mean operative time, mean length of hospital stay, and rate of postoperative complications were similar for primary and repeated TEM procedures (62.5 ± 17 versus 55 ± 23 minutes, P=.181; 1.7 ± 1.3 versus 1.7 ± 1.12 days, P=.99; and 35.7% versus 21.4%, P=.66, respectively). The Wexner score was comparable at baseline and after the first and the second TEM procedures (1.5 ± 2.3, 1.5 ± 2.3, and 3.3 ± 3.1, respectively; P=.188). No cases of fecal incontinence following a repeat TEM were documented.

CONCLUSIONS

Repeated TEM is feasible and safe and may be appropriate for selected patients.

Treatment of preoperatively diagnosed colorectal adenomas by transanal endoscopic microsurgery: the experience in China

INTRODUCTION

Colorectal adenoma is a recognized precancerous lesion that has the potential for malignant transformation. Surgical resection of colorectal adenomas is required for exact diagnosis and treatment. The aim of this study is to assess the safety and therapeutic effect of transanal endoscopic microsurgery for preoperatively diagnosed colorectal adenomas.

METHODS

From September 2006 to February 2011, 45 patients with preoperatively diagnosed colon and rectal adenomas underwent transanal endoscopic microsurgery. The clinical data of these patients were reviewed.

RESULTS

The mean tumor diameter was 2.2 cm, mean operative time was 65 min, and the mean estimated blood loss was less than 10 mL. There was no conversion to transabdominal procedure. The mean tumor distance from the anal verge was 8.2 cm. Four patients had perforation into the peritoneal cavity during full-thickness resection; these were repaired by continuous suturing, and there was no postoperative leakage after 1 week of fasting. The surgical margins of specimens were negative in 44 patients. Complications included rectal bleeding in one patient, acute urinary retention in one patient and pulmonary infection in one patient. The mean postoperative hospital stay was 4.5 days. Only one patient experienced incontinence of hard stool 6 months after surgery. The patients were followed up for a median period of 42 months, with four cases of tumor recurrence observed.

CONCLUSION

Transanal endoscopic microsurgery is a safe and effective technique for excising large adenomas in the mid and upper rectum and in the lower sigmoid colon. It is also an oncologically preferred method for T1 focal carcinomas that develop from villous adenomas.

Transanal endoscopic microsurgery: what indications in 2013?

Thanks to major advances in the field of surgical techniques and neoadjuvant chemoradiation therapy, along with more accurate pre-operative staging tools and the widespread introduction of population-based screening programs, treatment of rectal cancer has been evolving over the past few decades, moving towards a more tailored approach. This has brought a shift in the treatment algorithm of benign rectal lesions and selected early rectal cancers, for which today transanal endoscopic microsurgery (TEM) is accepted as an effective alternative to abdominal surgery.

In 2013, topics of controversy are the role of TEM in the treatment of more advanced rectal cancers, in cases of complete pathological response after chemoradiation therapy and the role of TEM as a platform for single-port surgery and NOTES. This article reviews the current indications for TEM and the future perspectives of this approach in the treatment of rectal tumors.

Transanal endoscopic microsurgery after neoadjuvant radiochemotherapy for locally advanced extraperitoneal rectal cancer: short-term morbidity and functional outcome

BACKGROUND

Transanal endoscopic microsurgery (TEM) after radiochemotherapy (RCT) has been reported in selected cases of locally advanced rectal cancer as an alternative to traditional radical resection with total mesorectal excision with a curative intent or as diagnostic tool to confirm a pathological complete response of the primary tumor. No study has evaluated functional outcome after TEM in preoperatively irradiated patients.

METHODS

This study was designed to evaluate short-term morbidity (according to Clavien's classifications) and establish (by a questionnaire) continence and evacuative function after RCT and TEM, at 1 year from surgery, analyzing the impact of RCT on postoperative outcomes. Patients with locally advanced rectal cancer treated by RCT and TEM (group 1) or with early T1 or adenomas treated only by TEM (group 2) entered this cohort comparative study.

RESULTS

Twenty-two patients entered the study as group 1 and 25 as group 2. No postoperative mortality occurred. The morbidity rate was 36.4 % in group 1 vs. 16 % in group 2 (p = 0.114). The rate of suture dehiscence was 22.7 % in group 1 vs. 4 % in group 2 (p = 0.068). No grade III complications, reoperation, or hospital readmission within 30 days was recorded in either group. One year after surgery, continence and evacuative scores in group 1 were 1.05 ± 1.25 and 24.72 ± 2.79, respectively, which were similar to group 2 (p = 0.081 and 0.288, respectively).

CONCLUSIONS

TEM after RCT in selected rectal cancer patients has an acceptable morbidity and functional results at 1 year from surgery. Preoperative irradiation could increase postoperative short-term morbidity, but it does not seem to influence evacuative or sphincter function after 1 year from surgery.

Transanal endoscopic microsurgery

The aim of oncologic surgery is radical cancer treatment with preservation of function and quality of life. Almost 30 years ago, transanal endoscopic microsurgery (TEM) revolutionised the technique and outcomes of transanal surgery, first becoming the standard of treatment for large rectal adenomas, then offering a possibly curative treatment for early rectal cancer, and finally generating discussion on its potential role in combination with neoadjuvant therapies for the treatment of more invasive cancer. TEM afforded the advantage of combining a less invasive transanal approach with low recurrence rates thanks to enhanced visualization of the surgical field, which allows more precise dissection. We describe the current indications, the preoperative work-up, the surgical technique (with the aid of a video), postoperative management and results obtained in an over 20-year-long experience. Designed as an accurate means to allow excision of benign rectal neoplasms with a very low morbidity rate, TEM today is indicated as a curative treatment of malignant neoplasms that are histologically confirmed as pT1 sm1 carcinomas. T1 sm2-3 and T2 lesions should at present be included in prospective trials. Accurate preoperative staging is essential for optimal selection of patients. Patients with clear indication for TEM should be referred to specialized medical centres experienced with the technique.

Transanal endoscopic microsurgery for rectal tumors: a review

Since its introduction in 1983, transanal endoscopic microsurgery (TEM) has emerged as a safe and effective method to treat rectal lesions including benign tumors, early rectal cancer, and rectal fistulas and strictures. This minimally invasive technique offers the advantages of superior visualization of the lesion and greater access to proximal lesions with lower margin positivity and specimen fragmentation and lower long-term recurrence rates over traditional transanal excision. In addition, over two decades of scientific data support the use of TEM as a viable alternative to radical excision of the rectum with less morbidity, faster recovery, and greater potential cost savings when performed at specialized centers.

Transanal endoscopic microsurgery is superior to transanal excision of rectal adenomas

AIM

Comparison of transanal excision (TE) and transanal endoscopic microsurgery (TEM) of rectal adenomas (RA) has rarely been performed.

METHOD

From 1990 to 2007, the results of TE (43 RA) and TEM (216 RA) were compared. Rectal adenomas were matched for diameter and distance from the anal verge.

RESULTS

Operation time was 47.5 min for TE and 35 min for TEM (P < 0.001). Morbidity was 10% after TE and 5.3% after TEM (P < 0.001). Negative resection margins were observed in 50% after TE and 88% after TEM (P < 0.001). Fragmentation of the excised specimen was observed in 23.8% after TE and 1.4% after TEM (P < 0.001). In cases of fragmentation, positive resection margins were observed more frequently. Recurrence was 28.7% after TE and 6.1% after TEM (P < 0.001). After TE, RA with a negative resection margin had a local recurrence rate of 0%, compared with 59.6% with a positive margin (P < 0.001), and after TEM these rates were 3.2 and 7.7% (P = 0.3), respectively.

CONCLUSION

Transanal endoscopic microsurgery is superior to transanal excision of RA.

Transanal endoscopic microsurgery for residual rectal cancer after neoadjuvant chemoradiation therapy is associated with significant immediate pain and hospital readmission rates

BACKGROUND

Transanal endoscopic microsurgery may represent appropriate diagnostic and therapeutic procedure in selected patients with distal rectal cancer following neoadjuvant chemoradiation. Even though this procedure has been associated with low rates of postoperative complications, patients undergoing neoadjuvant chemoradiation seem to be at increased risk for suture line dehiscence. In this setting, we compared the clinical outcomes of patients undergoing transanal endoscopic microsurgery with and without neoadjuvant chemoradiation.

METHODS

Thirty-six consecutive patients were treated by transanal endoscopic microsurgery at a single institution. Twenty-three patients underwent local excision after neoadjuvant chemoradiation therapy for rectal adenocarcinoma, and 13 patients underwent local excision without any neoadjuvant treatment for benign and malignant rectal tumors. Chemoradiation therapy included 50.4 to 54 Gy and 5-fluorouracil-based chemotherapy. All patients underwent transanal endoscopic microsurgery with primary closure of the rectal defect. Complications (immediate and late) and readmission rates were compared between groups.

RESULTS

Overall, median hospital stay was 2 days. Immediate (30-d) complication rate was 44% for grade II/III complications. Patients undergoing neoadjuvant chemoradiation therapy were more likely to develop grade II/III immediate complications (56% vs 23%; P = .05). Overall, the 30-day readmission rate was 30%. Wound dehiscence was significantly more frequent among patients undergoing neoadjuvant chemoradiation therapy (70% vs 23%; P = .03). Patients undergoing neoadjuvant chemoradiation therapy were at significantly higher risk of requiring readmission (43% vs 7%; P = .02).

CONCLUSION

Transanal local excision with the use of endoscopic microsurgical approach may result in significant postoperative morbidity, wound dehiscence, and readmission rates, in particular, because of rectal pain secondary to wound dehiscence. In this setting, the benefits of this minimally invasive approach either for diagnostic or therapeutic purposes become significantly restricted to highly selected patients that can potentially avoid a major operation but will still face a significantly morbid and painful procedure.

Functional and clinical results of transanal endoscopic microsurgery combined with endoscopic posterior mesorectum resection for the treatment of patients with t1 rectal cancer

BACKGROUND

Rectum-sparing transanal endoscopic microsurgery (TEM) is a well-established treatment for T1 carcinomas of the rectum. However, it is associated with an increased rate of local recurrence compared with extended resection. In most cases, this failure is linked to the presence of clinically nondetectable metastases in the regional lymph nodes. Endoscopic posterior mesorectal resection (EPMR) makes it possible to remove the relevant lymphatic drainage of the lower third of the rectum in the minimally invasive way, which can help with adequate tumor staging. The study evaluated the influence of combined TEM and EPMR treatment on the anorectal functions of this group of patients.

METHODS

Six consecutive patients (3 women and 3 men; mean age, 71.3 years) with T1 cancer of the rectum were operated on using TEM in combination with EPMR as a two-stage procedure between 2007 and 2009.

RESULTS

After a median follow-up of 19 (range, 8-30) months, none of our patients complained of symptoms of incontinence during the postoperative period apart from one woman with gas incontinence, who was diagnosed preoperatively. There was no statistically significant difference in BAP, SAP, HPZL, or in fecal continence control assessed using the Fecal Incontinence Severity Index before and 1, 3, and 6 months after the procedure. We observed one case of intraoperative complication (perforation) and one case of minor postoperative complication (hematoma formation). There was no evidence of locoregional recurrence.

CONCLUSIONS

EPMR in combination with TEM seems to be safe, feasible, and with no impact on the basic anorectal functions.

Synchronous colorectal neoplasias: our experience about laparoscopic-TEM combined treatment

Synchronous colorectal neoplasias are defined as 2 or more primary tumors identified in the same patient and at the same time. The most voluminous synchronous cancer is called "first primitive" or "index" cancer. The aim of this work is to describe our experience of minimally invasive approach in patients with synchronous colorectal neoplasias.Since January 2001 till December 2009, 557 patients underwent colectomy for colorectal cancer at the Department of General and Emergency Surgery of the University of Perugia; 128 were right colon cancers, 195 were left colon cancers while 234 patients were affected by rectal cancers. We performed 224 laparoscopic colectomies (112 right, 67 left colectomies and 45 anterior resections of rectum), 91 Transanal Endoscopic Microsurgical Excisions (TEM) and 53 Trans Anal Excisions (TAE). In the same observation period 6 patients, 4 males and 2 females, were diagnosed with synchronous colorectal neoplasias. Minimal invasive treatment of colorectal cancer offers the opportunity to treat two different neoplastic lesions at the same time, with a shorter post-operative hospitalization and minor complications. According to our experience, laparoscopy and TEM may ease the treatment of synchronous diseases with a lower morbidity rate.

The Ferguson Operating Anoscope as a Minimally Invasive Option for the Treatment of Rectal Tumors

Transanal excision of rectal tumors may be performed using the Ferguson Operating Anoscope (FOA). This retrospective case series evaluates the effectiveness of FOA for the excision of selected benign and malignant rectal tumors. The office records of 97 patients with rectal tumors who underwent FOA transanal excision by a single surgeon from 1999 through 2009 were reviewed. In the 97 patients evaluated, 99 FOA transanal excisions were performed for 39 adenocarcinomas, 55 benign tumors, and five carcinoid tumors. The tumors were 0.5 to 13.5 cm in diameter and located an average of 6.9 cm (range, 1 to 15 cm) from the anal verge. Ninety-one per cent of cases were performed as an outpatient. Postoperative complications occurred in 14 per cent with transient effects on continence in 2 per cent and a mean blood loss of 66 mL. The recurrence rate for favorable T1 rectal cancers was 4.3 per cent and for adenomas was 5.9 per cent. In early follow up of adenomas and favorable T1 carcinomas, FOA transanal excision has similar application, morbidity, and recurrence rates as reported for transanal endoscopic microsurgery for rectal tumors within 15 cm from the anal verge. FOA may be considered a useful option for the minimally invasive treatment of rectal tumors.

Transanal endoscopic microsurgery resection of rectal tumors: outcomes and recommendations

PURPOSE

Transanal endoscopic microsurgery provides a minimally invasive alternative to radical surgery for excision of benign and malignant rectal tumors. The purpose of this study was to review our experience with transanal endoscopic microsurgery to clarify its role in the treatment of different types of rectal pathology.

METHODS

A prospective database documented all patients undergoing transanal endoscopic microsurgery from October 1996 through June 2008. We analyzed patient and operative factors, complications, and tumor recurrence. For recurrence analysis, we excluded patients with fewer than 6 months of follow-up, previous excisions, known metastases at initial presentation, and those who underwent immediate radical resection following transanal endoscopic microsurgery.

RESULTS

Two hundred sixty-nine patients underwent transanal endoscopic microsurgery for benign (n = 158) and malignant (n = 111) tumors. Procedure-related complications (21%) included urinary retention (10.8%), fecal incontinence (4.1%), fever (3.8%), suture line dehiscence (1.5%), and bleeding (1.5%). Local recurrence rates for 121 benign and 83 malignant tumors were 5% for adenomas, 9.8% for T1 adenocarcinoma, 23.5% for T2 adenocarcinoma, 100% for T3 adenocarcinoma, and 0% for carcinoid tumors. All 6 (100%) recurrent adenomas were retreated with endoscopic techniques, and 8 of 17 (47%) recurrent adenocarcinomas underwent salvage procedures with curative intent.

CONCLUSIONS

Transanal endoscopic microsurgery is a safe and effective method for excision of benign and malignant rectal tumors. Transanal endoscopic microsurgery can be offered for (1) curative resection of benign tumors, carcinoid tumors, and select T1 adenocarcinomas, (2) histopathologic staging in indeterminate cases, and (3) palliative resection in patients medically unfit or unwilling to undergo radical resection.

A comparison of transanal excision and endoscopic resection for early rectal cancer

AIM: To compare the outcomes of endoscopic resection with transanal excision in patients with early rectal cancer.

METHODS: Thirty-two patients with early rectal cancer were treated by transanal excision or endoscopic resection between May 1999 and December 2007. The patients were regularly re-examined by means of colonoscopy and abdominal computed tomography after resection of the early rectal cancer. Complications, length of hospital-stay, disease recurrence and follow up outcomes were assessed.

RESULTS: Sixteen patients were treated by endoscopic resection and 16 patients were treated by transanal excision. No significant differences were present in the baseline characteristics. The rate of complete resection in the endoscopic resection group was 93.8%, compared to 87.5% in the transanal excision group (P = 0.544). The mean length of hospital-stay in the endoscopic resection group was 2.7 ± 1.1 d, compared to 8.9 ± 2.7 d in the transanal excision group (P = 0.001). The median follow up was 15.0 mo (range 6-99). During the follow up period, there was no case of recurrent disease in either group.

CONCLUSION: Endoscopic resection was a safe and effective method for the treatment of early rectal cancers and its outcomes were comparable to those of transanal excision procedures.

Surgical resection of rectal adenoma: A rapid review

Transanal excision (TE), endoscopic transanal resection (ETAR) and transanal endoscopic microsurgery (TEM) can be used to remove adenomatous polyps. However, their use is limited by the size or location of the tumor. TE is limited to the lower rectum, TEM offers better access to lesions in the middle and upper rectum, and ETAR is used less frequently than it deserves for resection of rectal lesions.

Endoscopy, morphology, morphometry and molecular markers: predicting cancer risk in colorectal adenoma

The evaluation of short- and long-term risk for developing cancer in patients with colorectal adenomas is controversial. Good, reliable predictors of cancer risk in any adenoma are currently lacking and are limited to adenoma size, number and histologic type. In fact, the evaluation of any adenoma or precancer lesion (e.g., hyperplastic polyps, serrated adenoma or aberrant crypt foci) within the colorectum may be assessed by a number of techniques ranging from direct visualization through the endoscope, to microscopic assessment, and to evaluation at the molecular level. Emerging techniques may yield improved methods of adenoma risk-assessment in the near future. For one, newer endoscopy technologies include chromoendoscopy or endocytoscopy, which now render endoscopists able to resolve the surface and subsurface mucosa at cellular resolution in vivo and in real time - thus, bringing the microscope to the patient's bedside. This new era in endoscopic imaging is dubbed 'histoendoscopy'. Further, while traditional views of classifying protruding and sessile lesions include those of Haggitt, the sm-classification, the Japanese and the so-called Vienna classifications to evaluate neoplasia, the development of new molecular techniques may give way to new methods of classifying preneoplasia and precancerous lesions. This review discusses some pros and cons of risk evaluation technologies in the colorectal tract by endoscopy, microscopy, and quantitative and molecular features. The morphometry-based studies performed over the past decades for the quantitative assessment of cellular and nuclear features within adenomas have failed to yield results amenable for clinical translation and are unlikely to improve further and gain widespread use with current technology. Rather, emerging knowledge of pathway-specific markers through the outlining of a molecular classification will likely be the basis for improved detection and diagnosis. The emerging genomic and proteomic technologies allowing for noninvasive tests to detect (asymptomatic) cancer and neoplasia are discussed. Lastly, the importance of recognizing bias and pitfalls and the adherence to guidelines for biomarker research are addressed.

Transanal endoscopic microsurgery is feasible for adenomas throughout the entire rectum: a prospective study

INTRODUCTION

Transanal endoscopic microsurgery for rectal adenomas is safe and has low recurrence rates. However, the feasibility of the procedure for all rectal adenomas is unclear. This issue was investigated prospectively.

METHODS

From 1996 to 2007, 353 consecutive rectal adenomas were evaluated according to a standard protocol. Transanal endoscopic microsurgery was intended in all rectal adenomas.

RESULTS

The median diameter was 3 cm and median distance was 8 cm. The peritoneum was opened peroperatively without any adverse effects in 8.7 percent. The conversion rate was 9.6 percent, with an alternative local procedure performed in 4.2 percent and a transabdominal procedure performed in 5.4 percent. Conversion rate correlated with the distance of the tumor (P = 0.007) and the operating surgeon's level of experience (P = 0.004). The median operation time was 45 minutes. Operation time correlated with specimen area, experience, and operating surgeon (all P < 0.001). All rectal adenomas were excised in one piece. Complete margins were observed in 85 percent. Rectal adenomas with incomplete margins were larger (P < 0.001) and were located more proximally (P < 0.001). Morbidity was 7.8 percent and mortality 0.6 percent. The median hospital stay was four days. The median follow-up was 27 months. The recurrence rate at three years was 9.1 percent. The median time from operation to recurrence was 12 (range, 4-54) months. Resection margin status was a predictor of recurrence, with 6.1 percent recurrence in cases of complete margins and 25.2 percent in cases of incomplete margins (P < 0.001).

CONCLUSIONS

For nearly all rectal adenomas, transanal endoscopic microsurgery is safe, feasible, and has excellent results.

Transanal endoscopic microsurgery: indications, results and controversies

Transanal endoscopic microsurgery (TEM) was introduced in 1983 as a minimally invasive technique allowing the resection of adenomas and early rectal carcinomas unsuitable for local or colonoscopic excision which would otherwise require major surgery. After 25 years, there is still much debate about the procedure. This article presents the TEM technique, indications, results and complications, focusing on its role in rectal cancer. The controversial points addressed include long-term results, TEM in high-risk T1 lesions, TEM associated with combined modality therapy (CMT) for invasive rectal cancer and salvage therapy after TEM. The future perspectives for TEM are promising and its association with CMT will probably expand the select group of patients who will benefit from the procedure.

Transanal endoscopic microsurgery versus endoscopic mucosal resection for large rectal adenomas (TREND-study)

Background

Recent non-randomized studies suggest that extended endoscopic mucosal resection (EMR) is equally effective in removing large rectal adenomas as transanal endoscopic microsurgery (TEM). If equally effective, EMR might be a more cost-effective approach as this strategy does not require expensive equipment, general anesthesia and hospital admission. Furthermore, EMR appears to be associated with fewer complications.

The aim of this study is to compare the cost-effectiveness and cost-utility of TEM and EMR for the resection of large rectal adenomas.

Methods/design

Multicenter randomized trial among 15 hospitals in the Netherlands. Patients with a rectal adenoma ≥ 3 cm, located between 1–15 cm ab ano, will be randomized to a TEM- or EMR-treatment strategy. For TEM, patients will be treated under general anesthesia, adenomas will be dissected en-bloc by a full-thickness excision, and patients will be admitted to the hospital. For EMR, no or conscious sedation is used, lesions will be resected through the submucosal plane in a piecemeal fashion, and patients will be discharged from the hospital. Residual adenoma that is visible during the first surveillance endoscopy at 3 months will be removed endoscopically in both treatment strategies and is considered as part of the primary treatment.

Primary outcome measure is the proportion of patients with recurrence after 3 months. Secondary outcome measures are: 2) number of days not spent in hospital from initial treatment until 2 years afterwards; 3) major and minor morbidity; 4) disease specific and general quality of life; 5) anorectal function; 6) health care utilization and costs. A cost-effectiveness and cost-utility analysis of EMR against TEM for large rectal adenomas will be performed from a societal perspective with respectively the costs per recurrence free patient and the cost per quality adjusted life year as outcome measures.

Based on comparable recurrence rates for TEM and EMR of 3.3% and considering an upper-limit of 10% for EMR to be non-inferior (beta-error 0.2 and one-sided alpha-error 0.05), 89 patients are needed per group.

Discussion

The TREND study is the first randomized trial evaluating whether TEM or EMR is more cost-effective for the treatment of large rectal adenomas.

Trial registration number

(trialregister.nl) NTR1422

Transanal endoscopic microsurgery is more effective than traditional transanal excision for resection of rectal masses

PURPOSE

Transanal endoscopic microsurgery, developed by Buess in the 1980s, has become increasingly popular in recent years. No large studies have compared the effectiveness of transanal endoscopic microsurgery with traditional transanal excision.

METHODS

Between 1990 and 2005, 171 patients underwent traditional transanal excision (n = 89) or transanal endoscopic microsurgery (n = 82) for rectal neoplasms. Medical records were reviewed to determine type of surgery, resection margins, specimen fragmentation, complications, recurrence, lesion type, stage, and size.

RESULTS

The groups were similar with respect to age, sex, lesion type, stage, and size. Mean follow-up was 37 months. There was no difference in the complication rate between the groups (transanal endoscopic microsurgery 15 percent vs. traditional transanal excision 17 percent, P = 0.69). Transanal endoscopic microsurgery was more likely to yield clear margins (90 vs. 71 percent, P = 0.001) and a nonfragmented specimen (94 vs. 65 percent, P < 0.001) compared with transanal excision. Recurrence was less frequent after transanal endoscopic microsurgery than after traditional transanal excision (5 vs. 27 percent, P = 0.004).

CONCLUSIONS

Transanal endoscopic microsurgery is the technique of choice for local excision of rectal neoplasms.

Transanal endoscopic microsurgery in early rectal cancer: time for a trial?

OBJECTIVE

The optimal aim of oncological surgery is to balance cancer outcomes with preservation of function and quality of life. Radical resection (RR) offers the best curative procedure in colorectal cancer but at significant morbidity. Transanal endoscopic microsurgery (TEM) offers an alternative with less morbidity and better function. Its role remains unclear and needs to be established in the light of new emerging trends in rectal cancer. This review aims to evaluate the use of TEM and its limitations.

METHOD

PubMed and MEDLINE search was performed.

RESULTS

Strongest level of evidence (Level II) favoured TEM over RR and laparoscopic resection in term of mortality and morbidity. There was no difference in recurrence at follow-up of 41 and 56 months but neither study was adequately powered to detect a difference in recurrence/survival. Three retrospective case comparisons (Level III) also favoured TEM over RR but were subject to selection bias. Twenty eight published case series (Level IV) reported varying results due to different cancer stages, study population, full excision, adjuvant therapy and treatment indication. The oncological outcomes in TEM are similar to RR in highly selected cases but with far less mortality (near 0%), morbidity, blood loss, hospital stay and genitourinary/gastrointestinal dysfunction. TEM alone (+/- adjuvant therapy) appears sufficient for 'favourable' T1 tumours. 'Unfavourable' T1 or T2 tumours require adjuvant treatment. TEM should only be used for palliation in T3+ cancers. Seven functional studies reported significant transient dysfunction following TEM with full clinical recovery within a year. TEM is cost-effective providing sufficient cases are performed.

CONCLUSION

Significant heterogeneity limits conclusions from current literature. A trial is required. Alternate end-points to local recurrence may be required in assessing the optimal surgical approach, which balances disease control with quality of life, and probability of noncancer related death.

Local excision and transanal endoscopic microsurgery in the management of rectal cancer with a focus on early carcinoma

Transanal endoscopic microsurgery (TEMS) will play an even greater role in the treatment of rectal cancer as the UK national colorectal cancer screening program becomes national. With more rectal tumors being uncovered at earlier stages, a greater emphasis will be placed on treatment options that do not involve radical surgery and the possibility of a stoma. This article reviews the data surrounding TEMS, focusing on its current role in the treatment of early rectal cancer but with a view on how this option may develop in the future, particularly with regards to the more advanced rectal cancers and in view of the improved chemoradiotherapy regimens available. The data is reviewed and some of the more controversial issues discussed.

Transanal endoscopic microsurgery for rectal tumors: the St. Mary's experience

BACKGROUND

The aim of this study is to describe a single institution's experience in the use of transanal endoscopic microsurgery for rectal tumors.

METHODS

Between 1996 and 2005, transanal endoscopic microsurgery was performed in 76 patients. The histologic diagnosis was adenoma in 48 and adenocarcinoma in 28 patients.

RESULTS

Clear resection margins were achieved in 71 of 74 patients (95.9%). Overall morbidity was 18.9% because 14 patients developed minor (10 patients) or major complications (4 patients). During the follow-up, benign tumor recurrence was detected in 3 patients (6.3%). The recurrence rates among patients with T1, T2, and T3 malignant tumors were 7.1%, 42.8%, and 66.6%, respectively.

COMMENTS

Transanal endoscopic microsurgery is a safe and feasible technique with low incomplete excision rates and may be the preferred method in patients with benign rectal tumors. Its role in the management of malignant tumors should be limited to selected patients with T1 lesions.

Single nucleotide polymorphism array analysis of chromosomal instability patterns discriminates rectal adenomas from carcinomas

Total mesorectal excision (TME) is the standard treatment for rectal cancer, while transanal endoscopic microsurgery (TEM) is a recently introduced surgical approach for the treatment of rectal adenomas. Incorrect preoperative staging before TEM is a problem. To identify genetic changes that might correlate with tumour stage and could lead to optimized treatment selection we performed a genome-wide chromosomal instability search in a homogeneous, clinical cohort of rectal tumours. 78 rectal tumours during different clinical stages were analysed with 10K single nucleotide polymorphism (SNP) arrays. Logistic regression was performed to build a quantitative model of specific chromosomal aberrations. Overall, most cases (95%) had one or more chromosomal aberrations. We observed a clear correlation between the total number of aberrations and the different tumour stages. Specifically, the chromosomal events: gain of 8q22-24, 13q and 20q, and loss of 17p and 18q12-22, were far more abundant in carcinoma than in adenoma. In adenoma fractions from cases with a carcinoma (infiltrating at least in the submucosa), twice the amount of such 'malignant aberrations' was observed, compared to pure adenomas. Furthermore, combined aberrations such as gain of 13q and loss of 18q were only found in adenomatous fractions of carcinomas and not in benign lesions. Based on these five genomic events associated with carcinoma, a clear distinction between adenoma and carcinoma tissue could be made. These data should be validated further in order that they may be used in preoperative staging of rectal tumours.

[Transanal endoscopic microsurgery (TEM). Current situation and future expectations]

Transanal endoscopic microsurgery (TEM) uses specific equipment that allows resection of large rectal adenomas and incipient malignancies in the rectal ampulla. TEM aims to provide an alternative to conventional abdominal surgery (low anterior resection or abdominoperineal amputations), which carries not inconsiderable morbidity and mortality. Application of the technique of endoanal excision is limited by the height and extension of the lesions. In this review, the authors present their own experience with this technique and that described in the literature. The protocol for selecting candidates for TEM, their preoperative preparation, equipment, characteristics of the surgical technique, postoperative complications, and follow-up are described. The collaboration of a multidisciplinary team is essential when developing this technique. TEM-associated morbidity is low and mortality is practically nil. TEM is the technique of choice in large rectal adenomas and malignant rectal tumors in stages pT1 localized in the rectal ampulla. The frequency of recurrence is similar to that in abdominal surgery. The technique does not cause complications of urinary or sexual dysfunction and fecal incontinence is minimal. In more advances stages of rectal cancer, the results of better patient selection and future studies on the possible application of neoadjuvant therapy associated with TEM are required.