6004 Background: Initial 3-year results from our clinical trial in locoregionally advanced nasopharyngeal carcinoma (NPC) patients showed that induction chemotherapy (IC) with cisplatin and fluorouracil (PF) resulted in improved disease-free survival (DFS) with a marginally significant effect on distant metastasis-free survival (DMFS), but the effect of IC on locoregional relapse-free survival (LRRFS) and overall survival (OS) did not differ significantly. Here, we present 5-year follow-up results. Methods: Our trial was a randomized, open-label phase 3 trial comparing IC followed by concurrent chemoradiotherapy (CCRT) versus CCRT alone in patients with stage III-IVB (except T3N0-1) NPC. The IC followed by CCRT group received cisplatin (80 mg/m² d1) and fluorouracil (800 mg/m² d1-5) every three weeks for two cycles before CCRT. Both groups were treated with 80 mg/m² cisplatin every three weeks concurrently with radiotherapy. The primary endpoints were DFS and DMFS. We did efficacy analyses in the 476 randomized patients (intention-to-treat population). Results: After a median follow-up of 82.6 months, the 5-year DFS rate was 73.4% (95% confidence interval (CI) 67.7-79.1) in the IC followed by CCRT group and 63.1% (95% CI 56.8-69.4) in the CCRT alone group (P = 0.005). The 5-year DMFS rate was also significantly higher in the IC followed by CCRT group (82.8%, 95% CI 77.9-87.7) than in the CCRT alone group (73.1%, 95% CI 67.2-79.0, P = 0.013). Our updated analysis revealed an OS benefit of IC: the 5-year OS rate was 80.8% in the IC followed by CCRT group versus 76.8% in the CCRT alone group (P = 0.045). There were no significant differences in the rate of grade 3–4 late adverse events during follow-up between the two groups. Conclusions: IC followed by CCRT provides long-term DFS, DMFS, and OS benefits compared with CCRT alone in locoregionally advanced NPC and, therefore, can be recommended for these patients. Clinical trial information: NCT00705627.
Long-term results of concurrent chemoradiotherapy for T3/T4 locally advanced nasopharyngeal carcinoma