PURPOSE: To investigate the prognostic value of biomarkers in male breast carcinoma (MBC). PATIENTS AND METHODS: Fifty patients (mean age, 62.2 years) with invasive ductal carcinoma were retrospectively studied. All patients received surgery; 35 had adjuvant postoperative therapy. The median follow-up was 59 months (range, 1 to 230 months). c-myc, c-erbB-2, p53, and bcl-2 proteins were immunohistochemically detected on sections from formalin-fixed, paraffin-embedded tissues using 9E11, CB11, DO7, and bcl-2 124 monoclonal antibodies (mAbs). Estrogen, progesterone, and androgen receptors were detected using specific mAbs. Cell proliferation was assessed by MIB-1 mAb. RESULTS: In univariate analysis, c-myc, c-erbB-2, and p53 protein overexpression was significantly correlated with prognosis. The median survival was 107 months for c-myc–negative and 52 months for c-myc–positive patients (P = .01), 96 months for c-erbB-2–negative and 39 months for c-erbB-2–positive patients (P = .02), and 100 months for p53-negative and 33 months for p53-positive patients (P = .0008). Tumor histologic grade (P = .01), tumor size (P = .02), patient age at diagnosis (P = .03), and MIB-1 scores (P = .0004) also had prognostic value. In multivariate analysis, only c-erbB-2 and p53 immunoreactivity retained independent prognostic significance. All nine patients who did not express c-erbB-2 and p53 proteins were alive after 58 months, whereas none of the 14 patients expressing both proteins survived at 61 months follow-up (P = .0002). CONCLUSION: Overexpression of c-myc, c-erbB-2, and p53 proteins may be regarded as an additional prognostic factor in MBC. The combination of c-erbB-2 and p53 immunoreactivity can stratify patients into different risk groups.