title: Screening in asymptomatic SDHx mutation carriers: added value of ¹⁸F-FDG PET/CT at initial diagnosis and 1-year follow-up.
abstract: OBJECTIVE
  Specific recommendations on screening modalities for paraganglioma (PGL) and phaeochromocytoma (PCC) in asymptomatic SDHx mutation carriers (relatives) are still lacking. We evaluated the added value of (18)F-FDG PET/CT in comparison with morphological imaging at initial diagnosis and 1 year of follow-up in this population.
  
  
  METHODS
  The study included 30 consecutive relatives with a proven SDHx mutation who were investigated by (18)F-FDG PET/CT, gadolinium-enhanced magnetic resonance angiography of the head and neck, thoracic/abdominal/pelvic (TAP) contrast-enhanced CT and/or TAP MRI. (123)I-MIBG scintigraphy was performed in 20 subjects and somatostatin receptor scintigraphy (SRS) in 20 subjects. The gold standard was based on pathology or a composite endpoint as defined by any other positive imaging method and persistent tumour on follow-up. Images were considered as false-positive when the lesions were not detected by another imaging method or not confirmed at 1 year.
  
  
  RESULTS
  At initial work-up, an imaging abnormality was found in eight subjects (27%). The final diagnosis was true-positive in five subjects (two with abdominal PGL, one with PCC and two with neck PGL) and false-positives in the other three subjects (detected with (18)F-FDG PET/CT in two and TAP MRI in one). At 1 year, an imaging abnormality was found in three subjects of which one was an 8-mm carotid body PGL in a patient with SDHD mutaion and two were considered false-positive. The tumour detection rate was 100% for (18)F-FDG PET/CT and conventional imaging, 80% for SRS and 60% for (123)I-MIBG scintigraphy. Overall, disease was detected in 4% of the subjects at the 1-year follow-up.
  
  
  CONCLUSIONS
  (18)F-FDG PET/CT demonstrated excellent sensitivity but intermediate specificity justifying combined modality imaging in these patients. Given the slow progression of the disease, if (18)F-FDG PET/CT and MRI are normal at baseline, the second imaging work-up should be delayed and an examination that does not expose the patient to radiation should be used.
authors: Department of Nuclear Medicine and Endocrine Oncology, Gustave Roussy Institut, Université Paris-Sud, 114 rue Edouard Vaillant, 94805, Villejuif, France, charlotte.lepoutre@inserm.fr.
authors: C
authors: C
authors: Lepoutre-Lussey
authors: C
authors: C
authors: Caramella
authors: F
authors: F
authors: Bidault
authors: D
authors: D
authors: Déandreis
authors: A
authors: A
authors: Berdelou
authors: A
authors: A
authors: Al Ghuzlan
authors: D
authors: D
authors: Hartl
authors: I
authors: I
authors: Borget
authors: A-P
authors: AP
authors: Gimenez-Roqueplo
authors: F
authors: F
authors: Dumont
authors: F
authors: F
authors: Deschamps
authors: C
authors: C
authors: Nascimento
authors: J
authors: J
authors: Lumbroso
authors: M
authors: M
authors: Guillaud Bataille
authors: M
authors: M
authors: Schlumberger
authors: E
authors: E
authors: Baudin
authors: S
authors: S
authors: Leboulleux
mesh_terms: D019797:3-Iodobenzylguanidine; D000293:Adolescent; D000310:Adrenal Gland Neoplasms / Q000000981:diagnostic imaging* / Q000235:genetics / Q000473:pathology; D000328:Adult; D000368:Aged; D058070:Asymptomatic Diseases; D005260:Female; D019788:Fluorodeoxyglucose F18; D006579:Heterozygote; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009154:Mutation; D010375:Pedigree; D010673:Pheochromocytoma / Q000000981:diagnostic imaging* / Q000235:genetics / Q000473:pathology; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D013385:Succinate Dehydrogenase / Q000235:genetics*; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D019797:3-Iodobenzylguanidine; D013385:Succinate Dehydrogenase