Prognostic value of metabolic tumor burden calculated using dual‐time‐point 18F‐fluorodeoxyglucose positron emission tomography/CT in patients with oropharyngeal or hypopharyngeal cancer

Background This study investigates the prognostic value of metabolic tumor burden calculated using dual‐time‐point 18F‐fluorodeoxyglucose positron emission tomography (FDG‐PET)/CT in patients with locally advanced cancer. Methods This study examines 42 patients (35 men and 7 women, 38‐73 years old) with locally advanced oropharyngeal or hypopharyngeal cancer who had undergone FDG‐PET/CT before receiving chemoradiotherapy. Maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured for the early and delayed phases. Statistical analyses included receiver operating characteristic curve, univariate and multivariate analysis. Results ΔSUVmax, both phases of MTV2.5 and TLG2.5, early TLG40%, ΔTLG2.5, and ΔTLG40% were significantly associated with progression‐free survival (PFS). In multivariate analysis, early TLG2.5 (P = .005) was an independent prognostic factor of PFS. Conclusion Not the percent change but the value calculated in the early phase in several parameters using dual‐time‐point FDG‐PET/CT is significantly associated with the outcomes of patients with locally advanced oropharyngeal or hypopharyngeal cancer.