癌中癌:乳癌轉移至腎臟癌—病歷報告
蔡維明
門諾醫院、外科部、泌尿科
Cancer-to-cancer metastasis: breast cancer metastasized into renal cell carcinoma—a case report
Wei-Min Tsai
Divisions of Urology, Department of Surgery, Mennonite Christian Hospital, Hualien, Taiwan
A 42-year-old female patient, a case of left breast mass with skin ulceration diagnosed by biopsy, was accidentally found to have right renal mass on CT (computerized tomography) during cancer staging workup. Metastases to axillary lymph nodes, bone and liver were also noted at the same time. Second opinion was sought from Urologist for the right renal mass while she underwent CCRT (combined chemo-radiotherapy). Biopsy of right renal mass revealed renal cell carcinoma (RCC) and radical nephrectomy was done 2 months after initial CCRT. Staging for the RCC was T1aN0M0 while breast cancer stage was T4N1M1.
There are 7 cases (including the current case) reported to have breast cancer metastasized into RCC. Their ages range from 42-75. Four of them have RCC on the same side as their breast cancers. Two of the cases are found only after autopsy. Time lapse in diagnosis of RCC after breast cancer is from one month to 30 years.
Less than 50 documented cases of cancer-to-cancer metastasis have been reported. RCC is the most common tumor found to coexist with other malignancies and is the recipient tumor in cancer-to-cancer metastasis in 65-75% of the reported cases. Because of the “terminal stages” when kidneys are involved in breast cancer patients, RCC may be underdiagnosed in these patients and cancer-to-cancer metastasis might be much more frequent.