MALIGNANT POLYPS: ONE SIZE DOES NOT FIT ALL

Aims The presence of high-risk features (HRF) predicting lymph node metastasis (LNM) and endoscopic piecemeal resection favors surgical approach in T1 colorectal cancer (CRC). The lack of consensus as to what constitutes HRF makes clinical decisions very challenging. Aim: to evaluate oncologic outcomes after malignant polyps’ endoscopic resection.

Methods Retrospective cohort study of patients submitted to endoscopic resection of pT1 CCR in a single-center multidisciplinary clinic (2012-2020). Clinical, endoscopic and histopathological data were collected. Malignant polyps were classified as high risk if≥1 are present: poor differentiation, deep submucosal invasion, lymphovascular invasion and positive resection margins. At the time of the study tumor budding was not considered a HRF.

Results We included 93 patients (71% male, mean age at diagnosis 67.4±10.3 years). Median follow-up was 33 months (IQR 25 – 48). Polyps were located in the rectosigmoid in 84% (n=77) and 72% (n=55) were pedunculated. There were 31% piecemeal resections. HRF were found in 64% (n=59) of the polyps. In 31% (n=18) surveillance was decided (no residual or recurrent cancer were registered). From 41 patients who underwent surgery, LNM were identified in specimen of 4 (all had more than one HRF). Distant metastasis at follow-up were found in 3 patients: 2 previously submitted to surgery without residual tumor or positive lymph nodes; 1 was not submitted to surgery because of the absence of HRF (Haggit 2). Considering recent guidelines, this patient would be have HRF (tumor budding).

Conclusions Our findings highlight the importance of complete histological reports, including tumor budding and stress the need to refine risk stratification.

Publication History

Article published online:
14 April 2022