Prognostic Value of Metabolic Tumor Volume Measured by (18)F-FDG PET/CT in Locally Advanced Head and Neck Squamous Cell Carcinomas Treated by Surgery.

Purpose: We assessed the prognostic value of metabolic tumor volume (MTV) measured using(18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) inpatients with locally advanced head and neck squamous cell carcinoma (HNSCC).
Methods: We retrospectively reviewed 56 patients (51 men, five women; mean age 56.0 ± 8.8years) who had locally advanced HNSCC and underwent FDG PET/CT for initial evaluation. All patients had surgical resection and radiotherapy with or without concurrent chemotherapy. The peak standardized uptake value (SUVpeak) and MTV of the target lesion, including primary HNSCC andmetastatic cervical lymph nodes, were measured from FDG PET/CT images. We compared SUVpeak, MTV, and clinicopathologic variables such as age, Eastern Cooperative Oncology Group (ECOG) performance status, pN stage, pT stage, TNM stage, histologic grade and treatment modality to disease-free survival (DFS) and overall survival (OS).
Results: On the initial FDG PET/CT scans, the median SUVpeak was 7.8 (range, 1.8-19.0) and MTV was17.0 cm(3) (range, 0.1-131.0 cm(3)). The estimated 2-year DFS and OS rates were 67.2% and 81.8%. The cutoff points of SUVpeak 6.2 and MTV 20.7 cm(3) were the best discriminative values for predicting clinical outcome. MTV and ECOG performance status were significantly related to DFS and OS on univariate and multivariate analyses (p < 0.05).
Conclusion: The MTV obtained from initial FDG PET/CT scan is a significant prognostic factor for disease recurrence and mortality in locally advanced HNSCC treated with surgery and radiotherapy with or without chemotherapy.