The unexpected finding of breast and axillary metastases in a patient with prostate carcinoma.

We report a rare case of breast and axillary metastases in a 75-year-old man diagnosed with prostate carcinoma. Initially, the patient presented with lower urinary tract symptoms (LUTS) and elevated prostate-specific antigen (PSA) levels. Prostate cancer was confirmed by biopsy and treated with androgen deprivation therapy (ADT) and radiotherapy. At the time the breast mass was detected, the patient was already undergoing ADT. Two years and 2 months after diagnosis, he developed a palpable mass in the left breast. Imaging and ultrasound-guided biopsy revealed metastatic prostate adenocarcinoma involving the breast and ipsilateral axillary lymph nodes, initially suspected as primary breast cancer or gynecomastia secondary to hormonal therapy. Systemic ADT was reinitiated, and palliative radiotherapy was administered to the breast. The patient responded favorably, with a significant PSA reduction and disease stabilization. This case emphasizes the importance of recognizing atypical metastatic sites in prostate cancer and the critical role of combined imaging and histopathological evaluation. Further research is needed to elucidate the mechanisms and clinical implications of such rare metastatic patterns.