APDW Surgical Forum August 2021
Title: Decisional conflict and bias in the interpretation of trials in minimally invasive rectal cancer surgery

Presenter: Michael J Solomon MSc DMed DMedSc FRACS FASCRS FRCSI
Professor of Surgical Research, University of Sydney

Minimally invasive options for rectal cancer (eg laparoscopy, robotic and taTME assisted resections) now compete not only with the conventional open approach but also “watch and wait” therapeutic radiotherapy policies and the horizon is changing rapidly and too fast for higher levels of evidence to catch up. With learning curves of >50 cases for each of these innovations how does one surgeon choose which operation they can train in and offer their patients. Can one surgeon truly become adept in all therapeutic options?

Randomised controlled trials remain at the top of the hierarchy of clinical research designs as they remain the best way to minimise both known and unknown selection bias. How have these RCT’s changed practice in rectal cancer minimally invasive surgery and how do surgeons interpret the results of RCT’s? What do we do when lower levels of evidence conflict with RCT’s in established treatments? Utilising laparoscopic colorectal cancer surgery as an example over the past 25 years, it would appear that as lower levels of evidence (eg historical control trials and retrospective cohorts) demonstrate large benefits of minimally invasive colorectal cancer there was little and slow uptake in the 1990’s and early 2000. As larger RCT’s defined little subjective benefit of minimally invasive surgery in colorectal cancer and more recently questioned the safety in rectal cancer surgery a linear increase in utilization occurs.