Background and Objectives: Estrogen receptors (ER) and progesterone receptors (PR) have been detected in both normal and malignant colonic mucosa, but the prognostic value of this observation is unknown. We aimed to define the prognostic significance of the presence of ER and PR in malignant cells from colorectal adenocarcinoma specimens. Methods: An immunohistochemical assay for ER and PR was performed on paraffinized sections from 65 colorectal adenocarcinoma specimens. Survival curves were analyzed to define the prognostic implications of ER and PR. Results: Twenty nine (45%) tumors tested receptor positive (32% for ER and 23% for PR). Tumors of advanced stage were more likely to express receptors than early stage tumors (56% vs. 32%; P ס 0.01). Median survival of patients with neoplasms expressing PR was 30 months. For patients whose tumors did not express any receptors, median survival had not been reached at the time of follow-up (P ס 0.04). Similarly, patients with tumors expressing both receptors had significantly reduced survival (median survival ס 20 months; P ס 0.003). Conclusions: Expression of receptors for sex steroids correlates with advanced stage disease. Expression of PR by the tumor cells is associated with a shorter patient survival. The results suggest that sex steroids may play a role in carcinogenesis and tumor progression.