Histologic evaluation of malignant polyps and low-stage colorectal carcinoma

Abstract

Context.-With widespread screening for colorectal cancer, the number of early-stage colorectal cancers is increasing. Local excision of pT1 tumors is associated with considerably less morbidity and mortality, but this must be weighed against risk of lymph node metastases. Objective.-To understand histologic prognostic factors associated with adverse outcome in malignant polyps. Data Sources.-Pertinent literature regarding histologic features of prognostic significance in malignant polyps and low-stage colorectal carcinomas is summarized and our institute's cases are used to highlight these histologic features. Conclusions.-Poor prognostic factors for malignant polyps include high tumor grade, presence of lymphovascular invasion, tumor less than 1 mm from resection margin, submucosal invasion deeper than 1 mm, and high tumor budding. These features should be assessed by the pathologist and communicated to the clinical team in order to allow proper management.