Breast Metastasis from a Renal Clear-Cell Carcinoma: a Rare Case Report and a Complex Review of Literature

Metastatic tumours account for < 1% of all breast malignancies. In most cases, their source is contralateral breast cancer. Renal cell carcinoma (RCC) metastases in the breast are extremely rare and have been sporadically recorded in the literature. We report about a 38-year-old Caucasian woman presented with a breast metastasis from clear-cell RCC five years after primary diagnosis. The patient was without clinical signs of recurrence of the disease until the follow up CT showing a suspicious mass in her left breast. A ultrasound guided large core-needle biopsy confirmed the diagnosis. Despite its rarity, breast metastases from RCC may occur up to ten years after radical nefrectomy. Differential diagnosis of metastatic extramammary breast tumours with primary breast carcinoma may be difficult. Histologic evaluation with immunohistochemistry (IHC) results frequently serve as important diagnostic tools for diagnosis. Surgical resection of the metastatic RCC is is usually the treatment of first choice.