Combination of pan-immune-inflammation value and frailty index predicts the outcomes of elderly nasopharyngeal carcinoma treated by concurrent chemoradiotherapy.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is increasingly diagnosed in elderly populations. However, prognostic tools that incorporate both tumor biology and host vulnerability remain limited. METHODS: In this retrospective cohort study, a total of 185 elderly patients (aged ≥65 years) with histologically confirmed NPC treated with concurrent chemoradiotherapy (CCRT) between March 2020 and June 2023 were evaluated. This study assessed the independent and combined prognostic value of the pan-immune-inflammation value (PIV) and frailty index for overall survival (OS) and progression-free survival (PFS). RESULTS: Both high PIV and frailty independently predicted shorter OS and PFS (p < 0.001). Combined classification into four subgroups yielded clear prognostic separation: Low PIV + Non-frail patients achieved the best 3-year OS (88.5%) and PFS (82.1%), whereas High PIV + Frail patients had the poorest outcomes (3-year OS 38.6%, PFS 30.4%). The combined model improved the C-index for OS prediction from 0.68 to 0.79 and the AUC for PFS from 0.70 to 0.81 compared with the baseline clinical models. Prognostic value remained robust in stage- and ECOG-stratified analyses with no significant interaction effects. CONCLUSION: The combination of PIV and frailty provides a highly discriminative prognostic tool in elderly NPC patients undergoing CCRT.