Identifying optimal candidates for induction chemotherapy among stage II-IVa nasopharyngeal carcinoma based on pretreatment Epstein-Barr virus DNA and nodal maximal standard uptake values of [18F]-fluorodeoxyglucose positron emission tomography

Objective This study aimed to select optimal candidates benefiting from the addition of induction chemotherapy (IC) to concurrent chemoradiotherapy (CCRT) in stage II-IVa nasopharyngeal carcinoma (NPC) based on Epstein-Barr virus (EBV) DNA and nodal maximal standardized uptake values (SUVmax-N) of [F-18]-fluorodeoxyglucose positron emission tomography. Patients and materials A total of 679 patients diagnosed with stage II-IVa (except N0) NPC were retrospectively included in this study. Overall survival was the primary endpoint. Survival differences between different groups were compared using the log-rank test. The hazard ratio (HR) and 95% confidence interval (CI) were calculated using a multivariable Cox proportional hazards model. Results Both high levels of EBV DNA (>1500 copies/mL) and SUVmax-N (>12.3) indicated worse survival conditions. All patients were divided into low- and high-risk groups based on these two biomarkers. The risk group was an independent prognostic factor in OS, progression-free survival (PFS), and distant metastasis-free survival (DMFS) (all p-values<0.05). The addition of IC to CCRT was associated with survival improvement in OS, PFS, and DMFS in high-risk patients, while no survival difference was found between CCRT and IC+CCRT in low-risk patients. Conclusions Our study can help clinicians select stage II-IVa NPC patients who benefit from IC, which is important in guiding individual treatment.