Which treatment for large rectal adenoma? Preoperative assessment and therapeutic strategy

In the present review the authors discuss the standard ways of preoperative work-up for a suspected large rectal non-invasive lesion, comparing East and West different attitudes both in staging and treatment. Looking at the literature and analyzing recent personal data, neither pit-pattern classification, nor EUS, nor biopsy histology, nor lifting sign verification, nor digital examination allow a specificity of more than three fourth of such cases. The authors disquisition about which optimal treatment excludes a role for EMR for the impossibility to obtain a single en-bloc specimen, minimum requirement for a correct lateral and vertical margin assessment. For the same reason ESD should be preferred, although a recent meta-analysis of the literature defined that one fourth of patients undergoing ESD for a preoperatively assessed non-invasive large rectal lesion fail to receive an R0 en-bloc resection. This forces about 10% of patients treated by flexible endoscopy to undergo abdominal surgery, which is about fourfold higher than TEM. While awaiting further implementation of modern technologies both to improve staging and to reduce invasiveness, a full-thickness excision of the rectal wall by TEM still represents the standard treatment even for suspected benign diseases.