Hans H Wasmuth1, Mahir Gachabayov, Les Bokey, Abe Fingerhut, Guy R Orangio, Feza H Remzi, Roberto Bergamaschi. 1. Department of Gastrointestinal Surgery, St. Olav's Hospital, Trondheim University Hospital, Trondheim, Norway Section of Colorectal Surgery, Department of Surgery, Westchester Medical Center, New York Medical College, Valhalla, NY, USA Department of Colorectal Surgery, Liverpool Hospital, Liverpool, New South Wales, Australia Department of Surgery, Medical University of Graz, Graz, Austria Section of Colorectal Surgery, Department of Surgery, Louisiana State University School of Medicine, New Orleans, LA, USA Inflammatory Bowel Disease Center, New York University Robert Grossman School of Medicine, New York University Langone Health, New York, NY, USA.
Abstract
BACKGROUND: A recent Norwegian moratorium challenged the status quo of transanal total mesorectal excision for rectal cancer reporting increased early multifocal local recurrences. OBJECTIVE: The aim of this systematic review and meta-analysis was to evaluate the local recurrence rates following transanal total mesorectal excision as well as to assess statistical, clinical, and methodological bias in reports published to date. DATA SOURCES: The Pubmed and MEDLINE (via Ovid) databases were systematically searched. STUDY SELECTION: Descriptive or comparative studies reporting rates of local recurrence at a median follow-up of 6 months (or more) after transanal total mesorectal excision were included. INTERVENTIONS: Transanal total mesorectal excision. MAIN OUTCOME MEASURES: Local recurrence was any recurrence located in the pelvic surgery site. Untransformed proportion method of one-arm meta-analysis was utilized. Untransformed percent proportion with 95% confidence interval was reported. Ad-hoc meta-regression with Omnibus test was utilized to assess risk factors for local recurrence. Among-study heterogeneity was evaluated: statistical by I2 and tau2, clinical by summary tables, and methodological by a 33-item questionnaire. RESULTS: Twenty-nine studies totaling 2,906 patients were included. The pooled rate of local recurrence was 3.4% (2.7%, 4.0%) at an average of 20.1 months with low statistical heterogeneity (I2=0%). Meta-regression yielded no correlation between complete total mesorectal excision quality (p=0.855), circumferential resection margin (p=0.268), distal margin (p=0.886), and local recurrence rates. Clinical heterogeneity was substantial. Methodological heterogeneity was linked to excitement of novelty, loss aversion, reactivity to criticism, indication for transanal total mesorectal excision, non-probability sampling, circular reasoning, misclassification, inadequate follow-up, reporting bias, conflict-of-interest, and self-licensing. LIMITATIONS: Included studies had observational design, limited sample and follow-up. CONCLUSION: This systematic review found a pooled rate of local recurrence of 3.4% at 20 months. However, given the substantial clinical and methodological heterogeneity across the studies, the evidence for or against transanal total mesorectal excision is inconclusive at this time.
BACKGROUND: A recent Norwegian moratorium challenged the status quo of transanal total mesorectal excision for rectal cancer reporting increased early multifocal local recurrences. OBJECTIVE: The aim of this systematic review and meta-analysis was to evaluate the local recurrence rates following transanal total mesorectal excision as well as to assess statistical, clinical, and methodological bias in reports published to date. DATA SOURCES: The Pubmed and MEDLINE (via Ovid) databases were systematically searched. STUDY SELECTION: Descriptive or comparative studies reporting rates of local recurrence at a median follow-up of 6 months (or more) after transanal total mesorectal excision were included. INTERVENTIONS: Transanal total mesorectal excision. MAIN OUTCOME MEASURES: Local recurrence was any recurrence located in the pelvic surgery site. Untransformed proportion method of one-arm meta-analysis was utilized. Untransformed percent proportion with 95% confidence interval was reported. Ad-hoc meta-regression with Omnibus test was utilized to assess risk factors for local recurrence. Among-study heterogeneity was evaluated: statistical by I2 and tau2, clinical by summary tables, and methodological by a 33-item questionnaire. RESULTS: Twenty-nine studies totaling 2,906 patients were included. The pooled rate of local recurrence was 3.4% (2.7%, 4.0%) at an average of 20.1 months with low statistical heterogeneity (I2=0%). Meta-regression yielded no correlation between complete total mesorectal excision quality (p=0.855), circumferential resection margin (p=0.268), distal margin (p=0.886), and local recurrence rates. Clinical heterogeneity was substantial. Methodological heterogeneity was linked to excitement of novelty, loss aversion, reactivity to criticism, indication for transanal total mesorectal excision, non-probability sampling, circular reasoning, misclassification, inadequate follow-up, reporting bias, conflict-of-interest, and self-licensing. LIMITATIONS: Included studies had observational design, limited sample and follow-up. CONCLUSION: This systematic review found a pooled rate of local recurrence of 3.4% at 20 months. However, given the substantial clinical and methodological heterogeneity across the studies, the evidence for or against transanal total mesorectal excision is inconclusive at this time.
Authors: Marta Sánchez-Díez; Nicolás Alegría-Aravena; Marta López-Montes; Josefa Quiroz-Troncoso; Raquel González-Martos; Adrián Menéndez-Rey; José Luis Sánchez-Sánchez; Juan Manuel Pastor; Carmen Ramírez-Castillejo Journal: Biomedicines Date: 2022-05-06