Chromogranin A assay and (131)I-MIBG scintigraphy for diagnosis and follow-up of pheochromocytoma.
We assessed the performance of a new serum chromogranin A (CgA) assay in combination with the results of (131)I-metaiodobenzylguanidine (MIBG) scintigraphy for diagnosis and follow-up in 89 patients with clinical findings suggestive of pheochromocytoma.


METHODS
The study population consisted of 41 patients with proven pheochromocytoma and 48 patients with refuted pheochromocytoma. Eighty-seven scintigraphy examinations were performed, 52 in patients with proven pheochromocytoma (39 before surgery and 13 after surgery) and 35 in patients with refuted pheochromocytoma.


RESULTS
The sensitivity of the CgA level was 90.2%, and the specificity was 99.0% and 92.3% in the control and refuted pheochromocytoma groups, respectively. A significant relationship was seen between serum levels of CgA and tumor mass (r = 0.70; P < 10(-5)). The postoperative CgA level was an early and accurate predictor of curative surgery or relapse. The concordance between CgA levels and scintigraphic data was 90.8%.


CONCLUSIONS
Serum CgA level is an effective marker of pheochromocytoma. Increased levels strongly correlate with tumor mass; therefore, small tumors may go undetected. The concordance between CgA level and the results of (131)I-MIBG scintigraphy is high. A CgA level in the reference range is highly predictive of normal scintigraphy findings.
d'Herbomez
M
M
Department of Nuclear Medicine, Center Hospitalier Universitaire de Lille, Lille, France.
Gouze
V
V
Huglo
D
D
Nocaudie
M
M
Pattou
F
F
Proye
C
C
Wémeau
J L
JL
Marchandise
X
X
D019797:3-Iodobenzylguanidine; D000310:Adrenal Gland Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000601:surgery; D014408:Biomarkers, Tumor / Q000097:blood; D053379:Chromogranin A; D002864:Chromogranins / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D010236:Paraganglioma, Extra-Adrenal / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000601:surgery; D010673:Pheochromocytoma / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D011446:Prospective Studies; D011859:Radiography; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity
D014408:Biomarkers, Tumor; C506150:CHGA protein, human; D053379:Chromogranin A; D002864:Chromogranins; D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine