The pathological classification of colorectal cancer.

The reporting and staging of large bowel cancer needs to be improved and refined. To achieve this end, the following steps should be adopted: All useful information should be utilised. Useful information has an independent bearing upon any clinically important end point, whether this be survival, local recurrence or response to treatment. Classifications should be based upon research that is carried out with meticulous care. It must be accepted that classifications may alter as new information comes to light. Different clinical settings will require different classifications. A classification only succeeds if it is applied correctly. Clinicians and pathologists require instruction on what to record and how to derive data with minimum effort and maximum accuracy. It is important that all terms are defined clearly and unambiguously. Finally classifications should be simple so that symbols can be readily equated with particular clinical endpoints. We have recently identified four pathological variables which influence long-term survival independently in patients undergoing curative surgery for rectal cancer. A new prognostic classification has been developed that is based on a simple scoring system for these variables. It is superior to staging by the method of Dukes because it places twice as many patients into groups that provide a confident prediction of clinical outcome.