Endocrine Combination Therapy for Prostate and Metastatic Breast Cancer in a Male Patient

Background: Breast cancer in men is rare and requires therapy concepts including health considerations different from those in female patients. Case Report: We report on a 64-year-old male patient with metastatic breast cancer in the lung and cervical lymph nodes. Upon metastasis, initial adjuvant endocrine therapy with tamoxifen was changed to anastrozole. After 1 year of treatment, the patient was found to have rising prostatespecific antigen (PSA) levels, and diagnostic workup confirmed the diagnosis of early prostate cancer. Because of simultaneous progressive disease of metastatic breast cancer, chemotherapy with 6 cycles of docetaxel was administered resulting in a partial remission of both tumor types. The patient is currently treated with an endocrine combination therapy of fulvestrant, goserelin, and bicalutamide. He is in good clinical condition, and tumor markers for both tumor types are stable. Conclusion: Elevated PSA levels under therapy with aromatase inhibitors have been described in individual cases but always warrant a careful diagnostic workup to exclude prostate cancer as an important differential diagnosis. Genetic counseling has to be taken into consideration in the case of male breast cancer as well as in the case of coincidence of different tumor types, such as breast and prostate cancer, due to the possibility of e.g. BRCA mutations in these patients.