18F-FDG PET/CT in the characterization and surgical decision concerning adrenal masses: a prospective multicentre evaluation.
OBJECTIVE
This prospective multicentre study assesses the usefulness of FDG PET/CT in characterizing and making the therapeutic decision concerning adrenal tumours that are suspicious or indeterminate in nature after conventional examinations (CE).


METHODS
Seventy-eight patients (37 men, 41 women, 81 adrenal lesions) underwent FDG PET/CT after CE including CT scan, biological tests and optionally (131)I-metaiodobenzylguanidine (MIBG) and/or (131)I-norcholesterol scans. FDG adrenal uptake exceeding that of the liver was considered positive. PET results were not decisive. Surgery was discussed when at least one of the following criteria was found during CE: size >3 cm, spontaneous attenuation value >10 HU, heterogeneous aspect, abnormal MIBG or norcholesterol scan or hormonal hypersecretion.


RESULTS
Following the gold standard (histology analysis or >or=9 months follow-up), 49 lesions potentially qualified for surgery (malignant = 27, benign secreting = 22) and 32 benign non-secreting lesions did not. PET was negative in 97% of non-surgical lesions and positive in 73% of potentially surgical ones which included all the malignant lesions, except 3 renal cell metastases, and 12 of 22 benign secreting lesions. The negative predictive value for malignancy was 93% (41/44) and positive predictive value for detecting surgical lesions was 97% (36/37). A high FDG uptake (maximum standardized uptake value >or= 10) was highly predictive of malignancy.


CONCLUSIONS
Adrenal FDG uptake is a good indicator of malignancy and/or of secreting lesions and should lead one to discuss surgery. If there is no prior history of poorly FDG-avid cancer, the absence of FDG uptake should avoid unnecessary removal of benign adrenal lesions.
Ansquer
Catherine
C
Service de Médecine Nucléaire, CHU-Hôtel Dieu, Nantes, France. catherine.ansquer@chu-nantes.fr
Scigliano
Sonia
S
Mirallié
Eric
E
Taïeb
David
D
Brunaud
Laurent
L
Sebag
Fredéric
F
Leux
Christophe
C
Drui
Delphine
D
Dupas
Benoît
B
Renaudin
Karine
K
Kraeber-Bodéré
Françoise
F
D000310:Adrenal Gland Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D012008:Recurrence; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
D019788:Fluorodeoxyglucose F18