Malignant Paraganglioma of the Prostate: Case Report, Depiction by Meta-iodobenzylguanidine Scintigraphy and Review of the Literature

Objective: To describe the 123-I-MIBG scintigraphic, CT, MRI, operative and pathological findings in a case of malignant prostatic paraganglioma and to review the literature on this very rare tumor.

Experimental Design: Clinical imaging and pathological correlation of data in a referred patient.

Setting: Regional referral center and tertiary referral academic medical center.

Patient: 17 year old man presenting with painless hematuria and a large prostatic mass. Interventions and measures. Renal ultrasound, transrectal ultrasound, ultrasound guided prostatic biopsy, pelvic CT and MRI, planar and SPECT 123-I-MIBG scintigraphy, and surgical exploration.

Results: The patient had a significant hydronephrosis of the left kidney and marked enlargement (120 ml) of the prostate gland by ultrasound. Ultrasound guided biopsies of the prostate and a left pelvic lymph node revealed a neuroendocrine tumor staining positive for chromogranin. CT and MRI revealed a large tumor of the prostate invading the seminal vesicles, bladder and rectum with extensive pelvic lymph node spread. The primary tumor and one of the nodes were shown to be 123-I-MIBG avid confirming the neuroendocrine nature of the tumor. The lesion was unresponsive to chemotherapy and unresectable at surgical exploration.

Conclusions: To date there have only been 5 reports of prostatic paragangliomas. To our knowledge this is the first to have been studied by MIBG scintigraphy and like most paragangliomas it was MIBG-avid.