A 59-year-old patient with an ovarian metastatic adenocarcinoma, presenting as bilateral axillary metastases associated with mastitis, underwent extensive primary abdominal cytoreductive surgery and bilateral axillary lymphadenectomy. Neoplastic axillary lymph node involvement and mastitis raised the issue of the clinical differential diagnosis between a primary breast cancer and a metastatic cancer. Preoperative clinical and radiologic investigation did not absolutely exclude the presence of a primary breast cancer, although the elevated serum CA 125 level (1024 UI/ml) suggested a possible primitive ovarian cancer. Pathologic examination of surgical material supported the ovarian origin of the adenocarcinoma, a poorly differentiated papillary serous type. The mammary erythematosus cutaneous changes were interpreted as effects of axillary lymphatic neoplastic block. In fact, after the last chemotherapy course, the breast healed without sequelae. Because the clinical presentation of metastases to the breast or axillary lymph nodes or both may strongly mimic primary breast cancer, their clinicopathologic recognition is crucial in planning appropriate treatment and follow-up.
