title: Transformation of a Nonfunctional Paraganglioma With I-123 MIBG Scintigraphy Correlation: A Case Report.
abstract: A 35-year-old woman presenting with abdominal pain was found to have mildly elevated catecholamine levels and a retroperitoneal mass. The patient underwent a negative I-123 MIBG scintigraphy scan and a nondiagnostic fine needle aspiration. Eleven years later the patient presented with a hypertensive emergency and markedly elevated catecholamine levels. A subsequent I-123 MIBG scintigraphy scan showed intense uptake corresponding to the previously seen retroperitoneal mass. The patient underwent surgical resection and pathology confirmed the presence of a paraganglioma. A paraganglioma is an extra-adrenal pheochromocytoma that contains chromaffin cells and is thus capable of producing catecholamines. I-123 metaiodobenzylguanidine (MIBG) scintigraphy has become the imaging study of choice for paragangliomas and has a sensitivity of ∼77% to 100% in detecting functional paragangliomas. This case demonstrates scintigraphic correlation of the functional transformation of a nonfunctional paraganglioma in a time span of ∼10 years. Although there are previously published case reports of scintigraphic positive, nonfunctional paragangliomas and scintigraphic negative chromaffin cell tumors, there has been no prior documented case of scintigraphic transformation on MIBG.
authors.affiliation: From the Department of Radiology (EAD, JC, HD, DB, JS); and Department of Pathology, Harbor-UCLA Medical Center, Torrance, CA (HS).
authors.forename: Eric A
authors.initials: EA
authors.lastname: Davalos
authors.forename: John
authors.initials: J
authors.lastname: Cho
authors.forename: Hiren
authors.initials: H
authors.lastname: Dave
authors.forename: Hong
authors.initials: H
authors.lastname: Shen
authors.forename: David
authors.initials: D
authors.lastname: Barank
authors.forename: John
authors.initials: J
authors.lastname: Shim
mesh_terms: D019797:3-Iodobenzylguanidine; D000328:Adult; D002395:Catecholamines / Q000652:urine*; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D010235:Paraganglioma / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000652:urine; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012186:Retroperitoneal Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000652:urine
chemical_list: D002395:Catecholamines; D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine