The impairment of induction chemotherapy for stage II nasopharyngeal carcinoma treated with intensity-modulated radiotherapy with or without concurrent chemotherapy: A propensity score-matched analysis

Abstract

Objectives: To explore the efficacy of induction chemotherapy (IC) plus concurrent chemoradiotherapy (CCRT) in stage II nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT).

Methods: Totally, 450 eligible patients with staged II NPC on the basis of the 8th edition of the AJCC/UICC TNM staging system were eventually included from January 2010 to September 2020. The one-to-one propensity score-matched (1:1 PSM) analysis was employed to balance variables. We conducted univariate and multivariate analysis of survival to identify prognostic factors and demonstrated the findings in the matching cohort.

Results: In total, 141 pairs were selected by 1:1 PSM. IC + CCRT group in the matched data decreased 5-year progression-free survival (PFS, 75.5% vs. 88.0%, p = 0.032) and distant metastasis-free survival (DMFS, 86.0% vs. 96.5%, p = 0.009). There was no significant difference in 5-year overall survival (OS, 93.8% vs. 95.6%, p = 0.192) and locoregional relapse-free survival (LRRFS, 87.1% vs. 94.3%, p = 0.169) compared with RT/CCRT. Multivariate analysis indicated that IC + CCRT was associated with significantly poor PFS (p = 0.024) and DMFS (p = 0.010). High neutrophil-to-lymphocyte ratio (>4.1) was negatively associated with OS (p = 0.034), PFS (p = 0.017) and DMFS (p = 0.001).

Conclusion: Adding IC to CCRT or IMRT alone has decreased PFS and DMFS, therefore, IC should not be recommended in stage II NPC patients. No significant differences in OS and LRRFS were observed in stage II disease.

Keywords: concurrent chemoradiotherapy; induction chemotherapy; intensity-modulated radiotherapy; nasopharyngeal carcinoma; propensity score-matched analysis.