Prognostic value of FDG-PET volumetric parameters in patients with p16-positive oropharyngeal squamous cell carcinoma who received curative resection followed by postoperative radiotherapy or chemoradiotherapy.

BACKGROUND The purpose of this study was to determine whether pretreatment 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) volumetric parameters add more prognostic information to p16-positive oropharyngeal squamous cell carcinoma (SCC). METHODS We retrospectively analyzed 86 patients with p16-positive oropharyngeal SCC who underwent surgery and postoperative radiotherapy (RT) or chemoradiotherapy (CRT). Maximum standardized uptake value (SUVmax ), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured. RESULTS Higher total MTV (tMTV), nodal MTV (nMTV), and tumor TLG (tTLG) were significantly associated with lower disease-free survival (DFS) (all p < .05) and higher distant metastasis rates (all p < .05). Multivariate analysis of DFS revealed that tMTV (p = .032), nMTV (p = .004), and tTLG (p = .018) were independently significant prognosticators. CONCLUSION Patients with p16-positive disease with high metabolic tumor burden were associated with higher distant metastasis rates, translating into worse survival. These patients may not be optimal candidates for treatment deintensification. © 2016 Wiley Periodicals, Inc. Head Neck 38: First-1524, 2016.