Abstract
The patient was 71-year-old-woman who had undergone left total nephrectomy for the treatment of left renal cell carcinoma 21 years ago, with no subsequent recurrence. In October 2012, she visited our hospital because she noticed a tumor mass in her left breast. Physical examination revealed a mass of approximately 3.5 cm in diameter in the CD area of her left breast. We performed core needle biopsy (CNB). A comparison of the CNB specimen with that of the renal primary lesion removed by her previous doctor revealed similarities, so we diagnosed the patient with left breast metastasis from renal cell carcinoma. No abnormal uptake area was observed on PET examination except for in the left breast area ; therefore, we ultimately diagnosed the patient with solitary metastasis to the mammary gland from renal cell carcinoma, and we subsequently excised circularly a part of her left breast. The patient is still alive without any recurrence at two years after the surgery without undergoing further treatment. In the case of renal cell carcinoma, possible metastasis and recurrence must be thoroughly considered, even if a long period has passed since the surgery.
