Combining cetuximab with chemoradiotherapy in patients with locally advanced nasopharyngeal carcinoma: A propensity score analysis

To compare the effectiveness of concurrent cisplatin chemoradiotherapy plus cetuximab with that of concurrent chemoradiotherapy (CCRT) alone in locoregionally advanced nasopharyngeal carcinoma (LRANPC) patients.A total of 3257 LRANPC patients from a prospectively maintained database were included in this observational study to examine the effectiveness of adding cetuximab to CCRT. We compared overall survival (OS), disease-free survival (DFS), locoregional recurrence-free survival (LRRFS), and distant metastasis-free survival (DMFS) using the propensity score method.In this cohort, 131 patients received CCRT plus cetuximab. Cetuximab-treated patients were more likely to receive intensity-modulated radiation therapy and were less likely to receive induction chemotherapy or adjuvant chemotherapy. The addition of cetuximab was associated with increased DMFS compared with CCRT alone based on univariable and multivariable analyses (5-year OS, 94.1% vs. 87.3%; P=0.044), but not with increased OS, DFS, or LRRFS. Propensity score matching identified 96 patients in each cohort and confirmed that a DMFS benefit was associated with the addition of cetuximab (HR, 0.38; 95% CI, 0.15-0.99, P=0.044). Subgroup analyses demonstrated a significant DMFS benefit with CCRT plus cetuximab in patients with N2-N3 stage disease compared with N2-N3 patients receiving CCRT alone (87.9% and 66.2%, respectively; P=0.045).In conclusion, the addition of cetuximab to first-line chemoradiotherapy is associated with an improvement in DMFS in patients with LRANPC. A prospective randomized clinical trial will be necessary to validate this result.