Prognostic significance of wait time for radical radiotherapy in locoregionally advanced nasopharyngeal carcinoma

Background The prognostic significance of wait time between definite diagnosis and initial radical radiotherapy is not well established in patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC) receiving both induction chemotherapy (IC) and concurrent chemoradiotherapy (CCRT). Methods From 2010 to 2018, 648 patients with LA-NPC treated with IC followed by CCRT were included. Results A total of 172 pairs of patients with LA-NPC were selected by propensity score matching (PSM). Compared to patients with an acceptable wait time (<= 75 days), patients with a prolonged wait time (>75 days) had a significant lower 5-year DMFS rate (86.6% vs. 74.1%, p = 0.006). Subgroup analyses indicated that the unfavorable effects of longer waiting times were mainly seen among stage IVa patients. Conclusions A prolonged wait time (>75 days) between definite diagnosis and initial radical radiotherapy has negative prognostic effects on patients with LA-NPC receiving IC plus CCRT, particularly those with IVa stage.