A case of malignant paraganglioma of the urinary bladder treated with cyclophosphamide, vincristine, and dacarbazine chemotherapy and metaiodobenzylguanidine therapy

Abstract

A 34-year-old man, diagnosed with paraganglioma of the urinary bladder, was referred to our hospital. Computed tomography showed a bladder tumor measuring 64 mm along with right obturator lymphadenopathy. Abnormal uptake was observed on 123 I-MIBG scintigraphy. The tumor was, therefore, diagnosed as malignant paraganglioma. We performed cystectomy, pelvic lymph node dissection, and neobladder reconstruction. Pathological examination revealed a malignant paraganglioma of the urinary bladder with right obturator lymph node metastasis. Postoperatively, both the uptake on 123 I-MIBG scintigraphy and catecholamine levels in blood and urine normalized. However, 22 months later, positoron emission tomography-computed tomography showed the presence of 2 recurrent tumors in the pelvis. The patient underwent 9 courses of cyclophosphamide, vincristine, and dacarbazine chemotherapy and MIBG radiotherapy twice, following which the tumor size decreased by 35% and catecholamine levels normalized once again. At about 2 years of follow-up, the patient was found to be free of recurrence.