Performance de la 18FDG-TEP dans le dépistage de paragangliome chez des patients porteurs d’une mutation SDHx

Abstract

ObjectiveTo evaluate the performance of 18FDG-PET/CT for detecting infra-clinic paraganglioma (PGL) in SDHx mutation carriers (relatives). Patients and methodsSixty-six patients, from 13 distinct families underwent a genetic testing on the SHD genes between 2003 and 2012. Among the 45 patients with a mutation, 30 with a 18FDG-PET performed at initial work-up were included in this retrospective study. A gadolinium-enhanced magnetic resonance angiography of the neck (angio-MR) was performed in all cases, a thoracoabdominal-pelvic contrast-enhanced computed tomography (TAP-CT) in 25 cases, a TAP-MR in 20 cases, a 123I-metaiodo-benzylguanidine scintigraphy (123I-MIBG) in 20 cases and a somatostatin receptor scintigraphy (SRS) in 20 cases. Gold standard was histologic or composite (confirmation by another imaging method and follow-up). ResultsA tumor was found in five subjects: 2 abdominal PGL, 1 pheochromocytoma and 2 PGL of the neck. The sensitivity of 18FDG-PET was 100 %, of SRS was 80 %, of 123I-MIBG was 60 % and of anatomical imaging (association between angio-MR of the neck and TAP-CT and/or TAP-MR) was 100 %. Three false positive lesions were described: 2 with the 18FDG-PET imaging and 1 with the TAP-MR technique. Conclusion18FDG-PET/CT is an excellent tool for screening SDHx relatives and should be completed by an angio-MR of the neck if suspicion of abnormality. Association of angio-MR of the neck and TAP-MR has the advantage of being a non-irradiating imaging method but with limited access in some countries.