[Non-muscle invasive bladder cancer with multiple bone metastasis without local invasion : a case report].

A 66-year-old man with superficial bladder cancer was treated with transurethral resection (TURBT) in October 2011. The pathological diagnosis was urothelial carcinoma (UC), grade 2, T1. A second TURBT was performed one month later. The pathological diagnosis was UC, grade 3, T1. He was treated with intravesical bacillus Calmette-Guerin (BCG) after TURBT. His progress was satisfactory, but a small superficial bladder cancer was found on cystoscopy in August 2012. He was going to be treated with TURBT, but the serum alkaline phosphatase level was abnormally high on preoperative evaluation. Bone scintigraphy showed multiple bone metastases from non-muscle invasive bladder cancer (NMIBC) without local invasion. He was started on combined chemotherapy with 1,000 mg/m2 gemcitabine on days 1, 8 and 15 and 70 mg/m2 cisplatin on day 2 every four weeks. He received denosumab for multiple bone metastases at the same time. Although he subsequently developed severe hypocalcemia, treatment was continued, and he completed four courses of chemotherapy. Bone scintigraphy and contrast-enhanced computed tomography showed reduction of the multiple bone metastases, and alkaline phosphatase decreased to the normal range. It is rare for NMIBC without local invasion to metastasize to other organs. Thus, it is necessary to consider distant metastases in patients with NMIBC.