[Distant Metastasis in Patients with Non-Muscle Invasive Bladder Cancer without Local Recurrence : Report of Two Rare Cases].

Distant metastasis is rare in patients with non-muscle invasive bladder cancer (NMIBC). We describe two cases of NMIBC with distant metastasis diagnosed in the follow-up period after transurethral resection (TUR), with neither intravesical recurrence nor progression to muscle-invasive disease. Case 1 : A 77-yearold man was referred to our hospital for treatment of a bladder tumor with the complaint of asymptomatic gross hematuria. TUR of the bladder tumor was performed. Pathological examination revealed high grade urothelial carcinoma pT1. Second TUR was performed and pathological examination confirmed high grade urothelial carcinoma pT1 with lymphovascular invasion. The patient received standard BCG therapy and subsequently developed left leg pain and lumbago 10 months after initial diagnosis. Magnetic resonance imaging, computed tomography, and bone scintigraphy demonstrated no local recurrence, but revealed multiple bone and liver metastases. The patient died 15 months after initial diagnosis. Case 2 : A 70-year-old man was referred to our hospital for treatment of an incidental bladder tumor. TUR of the bladder tumor was performed and pathological examination confirmed high grade urothelial carcinoma pT1. Second TUR was performed and pathological examination revealed no residual tumor cells. 18Fflurodeoxyglucose (FDG) positron emission tomography/computed tomography confirmed increasing uptake of 18F-FDG in the retroperitoneal lymph nodes, 18 months after initial diagnosis. The patient underwent laparoscopic lymphadenectomy. Pathological examination demonstrated metastasis of the bladder cancer. Combined chemotherapy was initiated with gemcitabine and cisplatin consecutively. To date the patient survives without progression or new distant metastases after four cycles of chemotherapy.