Colorectal cancer: Lahey Clinic experience, 1972-1976. An analysis of prognostic indicators.

The records of 344 consecutive patients with colorectal cancer treated operatively at the Lahey Clinic from 1972 through 1976 were reviewed, and the effects of 41 clinical and pathologic variables on survival were analyzed. The variables associated with poorer five-year survival rates were advanced Dukes' stage, four or more positive nodes, blood vessel invasion, lymphatic invasion, circumferential involvement, and obstruction at initial presentation. As a group, patients with right colon cancers (cecum and ascending colon) had the best survival rates. When fistula formation or localized perforation had occurred, en bloc resection of locally involved adjacent viscera improved survival rates. These prognostic indicators aid in the selection of patients for wider colonic and mesenteric resections.