An univariate analysis of pathologic data of 987 patients with primary colorectal carcinoma treated over a period of 22 years was performed. Six variables such as tumor site, histologic type, depth of invasion, nodal involvement, distant metastases, histologic grade and tumor stage were tested for their prognostic value. 5-year survival rate was investigated. Patients with tumors in the left colon and rectum have shown a better prognosis than patients with tumors in the right colon (53-51% vs. 38% p = 0.0007). As regard histologic type non significant differences between mucinous and non-mucinous carcinoma was observed (44% vs 48% respectively p = 0.4). The depth of tumor invasion was an important prognostic factor; according to tumor infiltration patients can be divided in four groups (T1, T2, T3, T4) with 5-year survival rates of 80%, 74%, 39% and 16% respectively (p = 0.0000). Highly significant decrements in survival occurred when lymph node metastases were demonstrable (20% vs. 67% p = 0.0000). Prognosis was still strongly related to histologic grade, with significant difference in survival rates between G1 and G2-G3 tumors (71% vs. 48%-42% p = 0.0000). Finally prognosis was closely related to the stage of spread at the time of diagnosis.