[A Case of Bladder Metastasis from Invasive Ductal Carcinoma of the Breast-A Case Report].

We report a patient with left breast cancer who underwent total mastectomy and axillary dissection as primary surgery. The patient, a 78-year-old woman, noticed a tumor about 4 cm in the left breast. She was diagnosed with left breast cancer (cT2N2M0, cStage ⅢA). The pathology revealed invasive lobular carcinoma, 46×31 mm, ly(+), v(0), histological grade: 2, n2, hormone receptor positive, HER2 negative, and pStage ⅢA. We recommended adjuvant chemotherapy, but she did not desire. She started oral administration of an aromatase inhibitor and radiation therapy. When DFI was 3 years, an examination was carried out because the increase in CEA value, CT scan revealed a mass extending from the bladder. We suspected bladder cancer. She underwent a bladder biopsy. The result was bladder metastasis of breast cancer. Later, we introduced chemotherapy. Routine screening of the lower urinary tract is not necessary for all patients, but women with a history of breast cancer presenting with urinary symptoms should undergo a thorough examination of the urinary tract.