Bilateral testicular neuroblastoma. Scintigraphic depiction and therapy with I-131 MIBG.

The authors describe a 29-year-old man who had a 16-year history of neuroblastoma and uncommon manifestations. At age 13, he was diagnosed with stage III retroperitoneal ganglioneuroblastoma that was resected. Ten years later, bilateral testicular enlargement and a pelvic mass from infiltration of the neuroblastoma became palpable. Metastatic involvement was depicted with MIBG, a radiotracer that concentrates in tissues of the sympathetic nervous system. Using I-131 MIBG, the tumors were treated with therapeutic doses of radiation and a partial response was obtained. This case is unique because of the massive degree of bilateral testicular infiltration and its occurrence as a late manifestation of neuroblastoma in early adulthood.