Superiority of fluorodeoxyglucose positron emission tomography to other functional imaging techniques in the evaluation of metastatic SDHB-associated pheochromocytoma and paraganglioma.
OBJECTIVE
Germline mutations of the gene encoding subunit B of the mitochondrial enzyme succinate dehydrogenase (SDHB) predispose to malignant paraganglioma (PGL). Timely and accurate localization of these aggressive tumors is critical for guiding optimal treatment. Our aim is to evaluate the performance of functional imaging modalities in the detection of metastatic lesions of SDHB-associated PGL.


METHODS
Sensitivities for the detection of metastases were compared between [18F]fluorodopamine ([18F]FDA) and [18F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET), iodine-123- (123I) and iodine-131 (131I) -metaiodobenzylguanidine (MIBG), 111In-pentetreotide, and Tc-99m-methylene diphosphonate bone scintigraphy in 30 patients with SDHB-associated PGL. Computed tomography (CT) and magnetic resonance imaging (MRI) served as standards of reference.


RESULTS
Twenty-nine of 30 patients had metastatic lesions. In two patients, obvious metastatic lesions on functional imaging were missed by CT and MRI. Sensitivity according to patient/body region was 80%/65% for 123I-MIBG and 88%/70% for [18F]FDA-PET. False-negative results on 123I-MIBG scintigraphy and/or [18F]FDA-PET were not predicted by genotype or biochemical phenotype. [18F]FDG-PET yielded a by patient/by body region sensitivity of 100%/97%. At least 90% of regions that were false negative on 123I-MIBG scintigraphy or [18F]FDA-PET were detected by [18F]FDG-PET. In two patients, 111In-pentetreotide scintigraphy detected liver lesions that were negative on other functional imaging modalities. Sensitivities were similar before and after chemotherapy or 131I-MIBG treatment, except for a trend toward lower post- (60%/41%) versus pretreatment (80%/65%) sensitivity of 123I-MIBG scintigraphy.


CONCLUSIONS
With a sensitivity approaching 100%, [18F]FDG-PET is the preferred functional imaging modality for staging and treatment monitoring of SDHB-related metastatic PGL.
Timmers
Henri J L M
HJ
Reproductive Biology and Medicine Branch, National Institutes of Child Health and Human Development, Bethesda MD 20892-1109, USA. h.timmers@endo.umcn.nl
Kozupa
Anna
A
Chen
Clara C
CC
Carrasquillo
Jorge A
JA
Ling
Alexander
A
Eisenhofer
Graeme
G
Adams
Karen T
KT
Solis
Daniel
D
Lenders
Jacques W M
JW
Pacak
Karel
K
D019797:3-Iodobenzylguanidine; D000310:Adrenal Gland Neoplasms / Q000000981:diagnostic imaging* / Q000235:genetics; D000328:Adult; D004298:Dopamine / Q000378:metabolism; D005260:Female; D019788:Fluorodeoxyglucose F18; D018095:Germ-Line Mutation; D006801:Humans; D007506:Iron-Sulfur Proteins / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D010235:Paraganglioma / Q000000981:diagnostic imaging* / Q000235:genetics; D010673:Pheochromocytoma / Q000000981:diagnostic imaging* / Q000235:genetics; D049268:Positron-Emission Tomography; D013385:Succinate Dehydrogenase / Q000235:genetics*
D007506:Iron-Sulfur Proteins; D019788:Fluorodeoxyglucose F18; D019797:3-Iodobenzylguanidine; C108095:SDHB protein, human; D013385:Succinate Dehydrogenase; D004298:Dopamine