Abstract

Here, we report a 52-year-old man with pelvic neuroblastoma; to our knowledge, he is the oldest patient reported in the literature. A large retroperitoneal pelvic tumor was located between the bladder and rectum without any invasion to the adjacent organs. A 24-hour urine catecholamine examination revealed that vanillin mandelic acid excretion was above the normal range. The tumor was resected without any pelvic organ injuries. Histopathology showed pleomorphic cells with spindle-shaped vesicular nuclei. The immunostaining results for NB84, bcl-2, neuron-specific enolase, and CD56 were positive. CD99 showed weak cytoplasmic staining, which is consistent with a primitive neural or neuroectodermal-type neoplasm. However, NB84 positivity and an intact Ewing sarcoma gene locus (EWS) locus using fluorescence in situ hybridization analysis implied neuroblastoma. Appropriate immunohistochemical studies distinguished adult neuroblastoma from other differential diagnoses, especially primitive neuroectodermal tumor. Despite the low stage of the tumor, the patient’s age and the large size of the tumor necessitated 6 cycles of adjuvant combination chemotherapy. Radiotherapy was not indicated for the patient, but he was followed regularly by pelvic computed tomography. This patient has benefited from a tumor-free survival for up to 6 years. Neuroblastoma is a differential diagnosis in patients with a pelvic mass, and treatment may be given according to pediatric protocols.