A retrospective study of concurrent chemoradiotherapy plus S-1 adjuvant chemotherapy on curative effect for treatment of patients with N3 stage nasopharyngeal carcinoma

Abstract

Introduction

The purpose of this study was to analyze the efficacy and safety of concurrent chemoradiotherapy plus S-1 adjuvant chemotherapy for N3 stage nasopharyngeal carcinoma (NPC).

Methods

This study included 44 N3 stage NPC patients treated with concurrent chemoradiotherapy plus S-1 adjuvant chemotherapy. The intensity-modulated radiation therapy doses were planning target volume (PTV) 70–72 Gy for gross disease in the nasopharynx and 66–70 Gy for positive lymph nodes. The doses for high-risk- and low-risk region PTV were 60–62 and 54–56 Gy in 31–33 fractions. All patients received a concurrent chemotherapy program consisting of cisplatin 100 mg/m ², day 1, and the cycle repetition was every 21 days. The adjuvant chemotherapy program consisted of 4 cycles of S-1. The dose of S-1 was determined according to the body surface area (BSA): 40 mg twice a day for BSA <1.25 m ²; 50 mg twice a day for 1.25 m ²≤BSA<1.5 m ²; and 60 mg twice a day for BSA ≥1.5 m ². S-1 was given on days 1–28, given 6 weeks apart.

Results

All 44 patients completed at least 2 cycles of concurrent chemotherapy and 4 cycles of adjuvant chemotherapy. The total efficiency of therapy was 100.0%. The 3-year overall survival (OS), distant metastasis-free survival (DMFS), local-regional control, and progression-free survival rates were 86.4%, 84.1%, 97.7%, and 81.8%, respectively. There were no differences in the OS, DMFS, and efficiency between fast-fading group (reaching partial response before the second cycle of concurrent chemotherapy) and general-fading group (the rest of the group). The incidence of rash in the entire group was low, and there was also no association with prognosis.

Conclusion

In patients with N3 stage NPC, concurrent chemoradiotherapy plus S-1 adjuvant chemotherapy yielded an excellent survival benefit, and the toxicities were mild and tolerable. Distant metastasis was the main cause of treatment failure.