Our novel approach is a hybrid between transanal endoscopic microsurgery (TEM) and single-port laparoscopy that we have termed TransAnal Minimally Invasive Surgery (TAMIS). We report the clinical application of this technique and present preliminary data that show TAMIS to be an effective tool for resection of both malignant and benign lesions of the rectum. Over a 3-month period (May–July 2009) all patients with rectal lesions who were candidates for conventional transanal excision were offered the option to undergo TAMIS resection. Patients with biopsy-proven malignant lesions were required to undergo endorectal ultrasound preoperatively to determine tumor stage. To perform TAMIS, a single-incision laparoscopic surgery port (SILS Port, Covidien) is introduced into the anal canal by applying steady manual pressure. Once seated in position, endoscopic access to the rectal vault is gained and pneumorectum is established. With this access, ordinary laparoscopic instruments, including graspers, thermal energy devices, and needle drives, are used to perform the transanal excisions. Six patients, aged 43–85 years old (mean = 59.8), underwent TAMIS resection of rectal lesions. The average distance from the anal verge was 9.3 cm and the mean tumor diameter confirmed by pathology measured 2.93 cm. There were no conversions from TAMIS to conventional transanal excision. While the average operating time was 86 min, four of the six TAMIS resections (67%) were completed in less than 1 h. The mean set-up time was only 1.9 min and this may be one reason that the mean operative time was considerably less than the average operative time for TEM surgery (120–140 min). In short-term follow-up, there was no morbidity or mortality observed. TAMIS is a feasible alternative to TEM, providing its benefits at a fraction of the cost.

Transanal minimally invasive surgery: a giant leap forward

Background: The outcome of local excision of early rectal cancer using transanal endoscopic microsurgery (TEM) lacks consensus. Screening has substantially increased the early diagnosis of tumours. Patients need local treatments that are oncologically equivalent to radical surgery but safer and functionally superior. Methods: A national database, collated prospectively from 21 regional centres, detailed TEM treatment in 487 subjects with rectal cancer. Data were used to construct a predictive model of local recurrence after TEM using semiparametric survival analyses. The model was internally validated using measures of calibration and discrimination. Results: Postoperative morbidity and mortality were 14·9 and 1·4 per cent respectively. The Cox regression model predicted local recurrence with a concordance index of 0·76 using age, depth of tumour invasion, tumour diameter, presence of lymphovascular invasion, poor differentiation and conversion to radical surgery after histopathological examination of the TEM specimen. Conclusion: Patient selection for TEM is frequently governed by fitness for radical surgery rather than suitable tumour biology. TEM can produce long-term outcomes similar to those published for radical total mesorectal excision surgery if applied to a select group of biologically favourable tumours. Conversion to radical surgery based on adverse TEM histopathology appears safe for p T1 and p T2 lesions.

A predictive model for local recurrence after transanal endoscopic microsurgery for rectal cancer.

Background and study aim: Population screening for colorectal cancer (CRC) is expected to increase the number of pT1 CRCs. Local excision is an attractive treatment option, but is only oncologically safe in the absence of lymph node metastasis (LNM). A systematic review of the predictive value of pathological risk factors for LNM in pT1 CRC was conducted to provide data for an evidence-based decision regarding follow-up or radical surgery after local excision. Methods: PubMed was searched for reports on predictors of LNM in pT1 CRC. Published papers written in English and containing at least 50 patients were included. Meta-analyses were performed using Review Manager 5.1. Results: A total of 17 studies were included involving a total of 3621 patients with available nodal status. The strongest independent predictors of LNM were lymphatic invasion (relative risk [RR] 5.2, 95 % confidence interval [CI] 4.0 – 6.8), submucosal invasion ≥ 1 mm (RR 5.2, 95 %CI 1.8 – 15.4), budding (RR 5.1, 95 %CI 3.6 – 7.3), and poor histological differentiation (RR 4.8, 95 %CI 3.3 – 6.9). Limitations of the study were: results could not be stratified according to location in the colon or rectum; very early tumors removed by polypectomy without surgical resection were not included in the meta-analysis; and included studies were primarily from Asian countries and results therefore need to be verified in Western populations. Conclusion: The absence of lymphatic invasion, budding, submucosal invasion ≥ 1 mm, and poor histological differentiation were each associated with low risk of LNM. Risk stratification models integrating these factors need to be investigated further.

/pdf/predicting-lymph-node-metastasis-in-pt1-colorectal-cancer-a-4gi3advhq1.pdf

Predicting lymph node metastasis in pT1 colorectal cancer: a systematic review of risk factors providing rationale for therapy decisions

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

Transanal Endoscopic Microsurgery is more Effective than Traditional Transanal Excision for Resection of Rectal Masses

The aim of this study was to systematically review the evidence relating to the safety and efficacy of transanal endoscopic microsurgery, a relatively new technique used to locally excise rectal tumors, compared with existing techniques such as anterior resections and abdominoperineal resections or local excisions. We conducted a systematic review of comparative studies and case series of transanal endoscopic microsurgery from 1980 to August 2002. Three comparative studies (including one randomized, controlled trial) and 55 case series were included. The first area of study was the safety and efficacy of adenomas. In the randomized, controlled trial, no difference could be detected in the rate of early complications between transanal endoscopic microsurgery (10.3 percent) and direct local excision (17 percent) (relative risk, 0.61; 95 percent confidence interval, 0.29–1.29). Transanal endoscopic microsurgery resulted in less local recurrence (6/98; 6 percent) than direct local excision (20/90; 22 percent) (relative risk, 0.28; 95 percent confidence interval, 0.12–0.66). The 6 percent rate of local recurrence for transanal endoscopic microsurgery in this trial is consistent with the rates found in case series of transanal endoscopic microsurgery (median, 5 percent). The second area of study was the safety and efficacy of carcinomas. In the randomized, controlled trial, no difference could be detected in the rate of complications between transanal endoscopic microsurgery and direct local excision (relative risk for overall early complication rates, 0.56; 95 percent confidence interval, 0.22–1.42). No differences in survival or local recurrence rate between transanal endoscopic microsurgery and anterior resection could be detected in either the randomized, controlled trial (hazard ratio,1.02 for survival) or the nonrandomized, comparative study. There were 2 of 25 (8 percent) transanal endoscopic microsurgery recurrences in the randomized, controlled trial, but no figures were given for recurrence after anterior resection. In the case series, the median local recurrence rate for transanal endoscopic microsurgery was 8.4 percent, ranging from 0 percent to 50 percent. The third comparison was cost of the procedures. Transanal endoscopic microsurgery had both a lower recurrence rate and a lower cost than local excision or anterior resection for adenomas. Although the effectiveness of transanal endoscopic microsurgery could not be established for carcinomas, costs were lower than those for either anterior resection or abdominoperineal resection. The evidence regarding transanal endoscopic microsurgery is very limited, being largely based on a single relatively small randomized, controlled trial. However, transanal endoscopic microsurgery does appear to result in fewer recurrences than those with direct local excision in adenomas and thus may be a useful procedure for several small niches of patient types—e.g., for large benign lesions of the middle to upper third of the rectum, for T1 low-risk rectal cancers, and for palliative, not curative, use in more advanced tumors.

Transanal endoscopic microsurgery: a systematic review

PURPOSE: This study was undertaken for the comparison of local resection for early rectal carcinomas using transanal endoscopic microsurgery or anterior resection. METHODS: Data from 50 of 52 patients with proven adenocarcinoma (GI/II) and intraluminal ultrasound with Stage uT1 N negative (uTNM) were evaluated in a prospective randomized study with two therapeutic arms: transanal endoscopic microsurgery (TEM; n=24) or anterior resection (AR; n=26), performed under general anesthesia. RESULTS: Patients' ages and rectal tumor locations showed insignificant differences of distribution in comparison of TEM with AR (Welsh's alternatet-test;t-test). Local recurrence (4.2 percent) and five-year survival rates (96 percent) differed insignificantly (log-rank test). Early postoperative mortality was zero. Significant differences were found comparing time of hospitalization, loss of blood, operation time, and opiate analgesia (Welsh's alternatet-test; Wilcoxon's test; eachP< 0.05). Early and late morbidity differed considerably. CONCLUSIONS: Lower morbidity, similar local recurrence, and survival rates favor the TEM technique. Comparable results in survival rate to the gold standard (AR) are objective arguments for choosing the adequate surgical procedure. For early rectal cancer, the minimum invasive TEM technique should be preferred because of superior overview during operation with safer suturing after meticulous full wall thickness excision.

Surgical cure for early rectal carcinomas (T1). Transanal endoscopic microsurgery vs. anterior resection.

P1.15-05 Nintedanib in Combination with Nivolumab in Pretreated Patients with Advanced Adenocarcinoma of the Lung (AIO-TRK-0117 Phase IB/II Trial)

Predictive value of computed tomography on surgical resectability in locally advanced pancreatic cancer treated with multiagent induction chemotherapy: Results from a prospective, multicentre phase 2 trial (NEOLAP-AIO-PAK-0113).

Ralph Keller

Papers

Surgical cure for early rectal carcinomas (T1). Transanal endoscopic microsurgery vs. anterior resection.

P1.15-05 Nintedanib in Combination with Nivolumab in Pretreated Patients with Advanced Adenocarcinoma of the Lung (AIO-TRK-0117 Phase IB/II Trial)

Predictive value of computed tomography on surgical resectability in locally advanced pancreatic cancer treated with multiagent induction chemotherapy: Results from a prospective, multicentre phase 2 trial (NEOLAP-AIO-PAK-0113).