Differential sensitivities of primary tumor and lymph nodes to induction chemotherapy and definitive radiotherapy in nasopharyngeal carcinoma.

Abstract

e18037 Background: Risk factors associated with differential sensitivities of primary tumors and lymph nodes to induction chemotherapy and their impact on clinical outcome in nasopharyngeal carcinoma (NPC) patients are undetermined. Methods: During June 2017 to June 2022, 105 NPC patients treated with comprehensive induction chemotherapy and concurrent chemoradiotherapy in our institute were eligible for analysis. Logistic regression analysis was used to identify factors associated with differential sensitivities of primary tumors and lymph nodes to induction chemotherapy (IC). Correlation and regression analysis were used to investigate whether there was a linear relationship between the sensitivity to induction chemotherapy and the efficacy of chemoradiotherapy. COX regression models were used to find prognostic factors, and Kaplan-Meier survival analysis was used to compare prognostic differences among groups with different induction chemotherapy sensitivities. Results: The median patient follow-up time was 26.0 (95%CI: 23.0-34.0) months. Grouped according to the response of the tumor primary site and lymph nodes to induction chemotherapy, we identified potential risk factors associated with different response patterns: primary tumor non-responsive and lymph node non-responsive, performance status (PS) score (OR: 3.824, 95% CI: 1.005-14.558, p = 0.030) ; primary tumor non-responsive but lymph node responsive, hemoglobin level (OR: 1.033, 95% CI: 1-1.067, p = 0.039) ; primary tumor responsive but lymph node non-responsive, N stage (OR: 2.297, 95% CI: 0.103-0.857, p = 0.014), white blood cell count (OR: 1.32, 95% CI: 1.025-1.699, p = 0.030); lymphocyte count (OR: 3.499, 95% CI: 1.196-10.241, p = 0.018) and blood urea nitrogen (OR: 1.416, 95% CI: 1.055-1.901, p = 0.021); primary tumor responsive and lymph node responsive, N stage (OR: 2.02, 95% CI: 1.044-3.907, p = 0.033), red blood cell count (OR: 0.369, 95% CI: 0.157-0.865, p=0.018) and lymphocyte count (OR: 0.359, 95% CI: 0.151-0.856, p = 0.015). Tumor response 6 months after chemoradiotherapy was significantly associated with tumor response after induction chemotherapy (p = 0.037). Similarly, lymph node response 3 months after chemoradiotherapy was significantly associated with lymph node response after induction chemotherapy (p = 0.043). White blood cell count (HR: 1.327, 95% CI: 1.035-1.701, p = 0.026) and neutrophil count (HR: 1.405, 95% CI: 1.049-1.882, p = 0.022) was risk factors associated with progression free survival. Conclusions: In this study, we identified PS score and hemoglobin as potential factors associated with differential sensitivities of primary tumors and lymph nodes to induction chemotherapy in NPC. However, our study found the efficacy of induction chemotherapy could predict the efficacy of chemoradiotherapy or progression free survival.