A nomogram to predict survival and guide individualized induction chemotherapy in T3-4N1M0 nasopharyngeal carcinoma

Abstract

Induction chemotherapy (IC) plus concurrent chemoradiotherapy (CCRT) and CCRT alone were the optional treatment regimens for T3-4N1M0 nasopharyngeal carcinoma (NPC) patients. Therefore, we established a nomogram to predict clinical prognosis and guide individualized IC in T3-4N1M0 NPC. Overall, 699 T3-4N1M0 NPC patients treated with CCRT with or without IC between January 2010 and December 2018 were examined. Overall survival (OS) was the main endpoint. A nomogram was developed that included prognostic variables selected by multivariable analysis. The risk score, which was calculated according to the nomogram, was used for risk stratification. The survival difference of patients undergoing CCRT with or without IC was then compared in risk-stratified subgroups. The nomogram yielded C-indexes of 0.708 (95% confidence interval [CI]: 0.682-0.734) in the training cohort and 0.670 (95% CI: 0.625-0.715) in the validation cohort. Calibration curves for 1-, 3- and 5-year OS suggested a good association between the nomogram predicted and observed probabilities. High-risk patients stratified by nomogram benefited from IC (IC + CCRT vs CCRT: 5-year OS: 77.8% vs 58.8%; P = 0.040; 5-year disease-free survival: 75.0% vs 58.2%; P = 0.017), whereas in the low-risk group, the application of IC was associated with worse locoregional recurrence-free survival and distant metastasis-free survival. This nomogram can serve as a reliable model for prognostic prediction and can be used to guide individualized treatment of T3-4N1M0 NPC. High-risk patients are candidates for IC before CCRT, while the use of IC for low-risk patients should be considered carefully.

Keywords: Chemoradiotherapy; Induction chemotherapy; Nasopharyngeal carcinoma; Nomogram; Overall survival.