Cancer Can Be Accurately Predicted Endoscopically in Flat Colorectal Lesions; Nodular and Bulky Lesions, Not so Much
Douglas K. Rex, MD, MASGE, reviewing Vosko S, et al. Clin Gastroenterol Hepatol 2021 May 13.
Before endoscopic resection, large nonpedunculated colorectal lesions should be thoroughly inspected for evidence of submucosal invasive cancer (SMIC). The features to look for are disruption of the normal vascular and pit patterns, often accompanied by a morphologic change such as depression or ulceration. These endoscopic features have often been considered to be specific for SMIC but not sensitive.
In a new study from the Australian Colonic Endoscopic Resection cohort, the performance of optical evaluation was assessed in 1583 nonpedunculated lesions removed during a 6-year period. The overall sensitivity and specificity for SMIC were 67% and 95%, respectively. For flat compared to nodular lesions, the sensitivity was higher at 91% versus 53%, respectively, and the specificity was similar at 96% versus 94%, respectively. Multivariable predictors of SMIC were size ≥40 mm (odds ratio [OR], 2.0), rectosigmoid location (OR, 2.0), and nodular morphology (OR, 7.2).
COMMENTThese important and useful results fit with everyday experience that the endoscopic prediction of cancer is reliable for flat lesions, regardless of granular versus nongranular morphology. However, nodular components and 1s lesions are difficult to predict because the cancer may be sufficiently distant from the surface, and therefore, the surface patterns characteristic of SMIC may not be present and do not reflect the presence of cancer deeper in the lesion. As a concept, to some extent, “flat vs not flat” represents a useful simplification of the Paris classification. This knowledge can help guide the decision for en bloc versus piecemeal resection.
Note to readers: At the time we reviewed this paper, its publisher noted that it was not in final form and that subsequent changes might be made.
CITATION(S)
Vosko S, Shahidi N, Sidhu M, et al. Optical evaluation for predicting cancer in large non-pedunculated colorectal polyps is accurate for flat lesions. Clin Gastroenterol Hepatol 2021 May 13. (Epub ahead of print) (https://doi.org/10.1016/j.cgh.2021.05.017)
