Intérêt de la TEP/TDM au ~(18)F-FDG dans la neurofibromatose de type 1, expérience du centre national de référence Henri-Mondor sur 10 ans

摘要

Objective. - Malignant peripherals nerve sheath tumours (MPNST) are one of the leading causes of death in neurofibromatosis type 1 (NF1). Given the temporal and spatial multiplicity of suspicious lesions, the histological diagnosis of certainty might require iterative and decaying surgical procedure. Our objective was to determine the threshold values of metabolic metrics determined on F-18-FDG PET/CT (SUVmax, total lesion glycolysis [TLG], total metabolic tumour volume [TMTV], tumour-to-liver [T/L] ratio and heterogeneity index [HI]) in order to distinguish at best MPNST from benign lesion (simple neurofibromas [NF] or dysplastic NF).Patients and methods. - Hundred and seven patients from the national reference centre of NF1 Henri-Mondor, clinically suspects of TMGN, underwent 160 F-18-FDG PET/CT over a period of 10 years, between 2005 and 2015. The hypermetabolics lesions identified on F-18-FDG PET/CT were confronted with pathological analysis or clinico-radiological and metabolic follow-up of more than 6 months.Results. - Four hundred and eight hypermetabolics lesions were identified, of which 112 were histologically confronted with 38 simple NF, 29 dysplastic NF, 39 TMGN and 6 incidentalomas. The remaining 296 hypermetabolics lesions experienced a median follow-up of 40.4 months [13.5-137 months]. The optimal cut-off values for malignant lesions, determined by ROC curves, were in order of decreasing performance: TX ratio > 2.03 (sensitivity 96%, specificity 88%); SUVmax > 4.74 (sensitivity 93%, specificity 86%); TLG > 172 (sensitivity 84%, specificity 76%); TMTV > 53.5 (sensitivity 83%, specificity 68%); HI > 1.63 (sensitivity 84%, specificity 54%).Conclusions. - F-18-FDG PET/CT is a powerful diagnostic and prognostic tool in the management of TMGN. Metabolic metrics allow with good sensitivity and specificity to identify lesions transformed into TMGN. The advent of PET/MRI will undoubtedly allow in the near future to reinforce the diagnostic and prognostic performances for the detection of transformations of neurofibromas in TMGN. (C) 2019 Elsevier Masson SAS. All rights reserved.