Colonoscopic treatment of colon cancers.

Recent advances in endoscopic technology have enabled conservative treatment for patients with carcinoma in situ. The treatment of submucosally invasive carcinomas, or malignant polyps, is still controversial, however. The use of widely advocated histologic criteria, such as poorly differentiated histology (Grade III cancer), level 4 invasion or involved margin status, or lymphatic venous invasion as risk factors for adverse outcome, should be examined by multivariate analysis. Unfavorable histology at the invasive margin, PCNA, MUC-1 expression, and chromosomal abnormalities may be new candidates for prognostic indicators in patients with submucosally invasive carcinoma.