Apport d'un nouveau score visuel en TEP/TDM au 18Fluorodeoxyglucose (18FDG) lors des récidives ganglionnaires de cancer ORL après traitement initial

New visual score in PET/CT 18Fluorodeoxyglucose (18FDG) to evaluate lymph node recurrence of head and neck cancer after initial treatment. Neck dissection for node recurrence of head and neck cancer is known for important morbidity after initial radiation therapy. 18FDG PET/CT in this situation looks interesting but needs standardized interpretation. Our objective was to develop a PET/CT interpretation method in suspicious locoregional head and neck recurrence. Twenty-seven patients with suspicious lymph node recurrence after initial radiation ± chemotherapy for head and neck cancer were retrospectively included. 18FDG PET/CT was performed before neck dissection and histological data. Initial PET records, binary visual scale, five-point visual scale “Deauville like” and semi-quantitative index were assessed by 2 reviewers. A lymph node recurrence was confirmed in 19 patients (70%) based on histological results. PET records analysis found 6 false positive (FP), 2 true negative (TN) and 19 true positive (TP), with a sensibility (Se), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of 100%, 25%, 76% and 100%, respectively. Binary visual scale reclassified 1/6 FP. “Deauville like” criteria, reclassified 4/6 FP with the first reviewer (P < 0.001) and 5/6 with the second (P < 0.002), improving Sp and PPV of 66% and 95%, respectively. Kappa concordance coefficient for “Deauville like” scale was 0.88. Semi-quantitative index like SUVmax, SUVmean, SUVpeak, MTV, TLG and SAM showed no statistical value. Those preliminary results warrant a standardized visual scale, particularly the “Deauville like” criteria for 18FDG PET/CT interpretation in suspected lymph node recurrence of head and neck cancer.