Prognostic factors in node-negative male breast cancer

Background: Male breast cancer has traditionally been compared with female breast cancer, using the same staging system and prognostic indicators. A variety of histochemical and pathologic factors commonly used in node-negative female breast cancer were applied to 18 node-negative male breast cancers to assess their relevance to survival. Patients and Methods: A slide review was performed for nuclear grade, lymphocytic infiltration, and lymphatic and vascular invasion. Flow cytometry was available on all the specimens. Immunohistochemistry was used to assess p53, estrogen receptors (ERs), cathepsin D, Ki-67, and c-erbB-2 (HER2/neu). A clinical correlation was performed based on chart reviews and phone interviews, recording demographics, treatment, and long-term survival. Results: The average age at diagnosis was 64 years (range, 34-85 years). There were 15 T1 lesions, 2 T2 lesions, and 1 T3 lesion. All patients had a modified radical mastectomy. None received radiation therapy. The mean follow-up was 73 months. Three patients died of their disease (17.6%), 2 patients died from unrelated reasons, 1 patient was lost to follow-up, and the other 12 patients are alive with no evidence of disease. The actuarial 5-year survival was 83%. Estrogen receptor and HER2/neu overexpression were significantly more predominant in male breast cancer than in female breast cancer. Estrogen receptor positivity was present in 17 of 18 patients and HER2/neu overexpression in 10 of 18. A positive ER status and overexpression of cathepsin or p53 were correlated with a better survival, but only ER (P = 0.026) and p53 (P = 0.023) reached statistical significance. Conclusion: In this study, ER status was the only commonly used prognostic marker for female breast cancer found to be applicable in node-negative male breast cancer.