We have studied 191 protocolized colorectal cancer patients, analyzing the prognostic factors described in the literature as being important to long-term survival. Of the data studied, sex, age, duration of symptoms, tumor location, tumor extension within the circumference of the bowel lumen, and the surgical technique employed, all showed differences in terms of five-year survival, but without reaching statistical significance. The factors with statistically significant prognostic value were first symptoms, occlusion, perforation, primary tumor size and configuration, lymph node involvement, degree of wall infiltration, presence of emboli, degree of differentiation and Scarff index. In view of these results, we consider that the evaluation of bowel wall infiltration, lymph node involvement, venous and/or lymphatic embolization, and tumor differentiation is necessary to establish long-term prognosis in these patients. The remaining factors lack prognostic value.