[News on the surgical pathology of colorectal cancer]

The incidence of regional lymph node metastases in colorectal carcinoma is influenced primarily by depth of invasion, but also by histological grade of malignancy and histologically demonstrable invasion of lymphatics. With regard to the indication for limited treatment of colorectal carcinoma, a differentiation between high risk and low risk tumors is recommended. In 6% of tumors with regional lymph node metastases only micrometastases are observed whose prognostic significance is not yet established. In most cases, lymphatic spread occurs regularly, in conformity with the anatomical situation, skipping of lymph nodes in less than 2% of cases with lymph node metastasis can be observed. The incidence and topography of lymph node metastases are important for the choice of surgical procedures. Because of the observed behaviour in lymphatic spread extended hemicolectomies are recommended for tumors of the transverse colon and the colonic flexures. The surgical treatment of rectal carcinoma should include the systematic node dissection along the inferior mesenteric artery.