Pathology report in colon cancer: what is prognostically important?

Surgical resection is the primary treatment modality for colorectal cancer, and the most powerful tool for assessing prognosis following surgery is pathologic analysis of the resection specimen. Although the parameters that determine the pathologic stage are the strongest predictors of postoperative outcome, a number of additional pathologic features have prognostic significance that is independent of stage. These include: histologic grade; small vessel (lymphatic or venular) invasion; extramural venous invasion; perineural invasion; tumor border configuration; host lymphoid response to tumor, and the status of surgical margins. For specimens in which the radial (circumferential) margin is applicable, surgical clearance around the tumor is also of import. It is self-evident that, compared to data derived from additional assays, prognostic information that can be derived directly from standard histologic sections of a tumor is of the greatest cost-benefit to the patient. In the current era of cost containment, it is essential that surgical pathologists evaluate and report the pathologic features that are of prognostic and/or predictive significance in every case of colorectal cancer and, in turn, that the import of these be understood by the treating physicians.