Clinical significance of pretreatment metabolic tumor volume and total lesion glycolysis in hypopharyngeal squamous cell carcinomas.

Background: To evaluate the usefulness of metabolic tumor volume (MTV) and total lesion glycolysis (TLG) measured by pretreatment fluorine 18-fluorodeoxyglucose ((18) F-FDG) positron emission tomography (PET)/computed tomography (CT) as predictors of clinical outcome in hypopharyngeal squamous cell carcinoma (HPSCC).

Methods: Seventy-eight patients with HPSCC treated with definitive radiotherapy with or without chemotherapy underwent (18) F-FDG PET/CT. Maximum standardized uptake value (SUV max ), MTV, and TLG were measured. For calculation of MTV, 3-D regions of interest were drawn and a SUV threshold of 2.5 was used for defining region. Univariate and multivariate analyses identified variables associated with disease-free survival (DFS) and overall survival (OS).

Results: Median SUV max , MTV, and TLG were 9.0 (range, 1.7-24.5), 20.5 (0.3-339.9) ml, and 98.9 (0.8-1877.1) g, respectively. The four-year DFS and OS were 56.1% and 52.6%, respectively. On univariate and multivariate analyses, MTV (P = 0.014) and TLG (P = 0.029) were independent prognostic factors for DFS, and MTV (P = 0.002) and TLG (P = 0.002) were independent prognostic factors for OS.

Conclusions: MTV and TLG measured by pretreatment (18) F-FDG PET/CT may be useful in predicting the clinical outcomes of HPSCC patients undergoing radiotherapy.