Purpose: To retrospectively assess the safety profile of chemoradiation (CRT) with S-1 for oropharyngeal and hypopharyngeal squamous cell carcinoma (SCC).
Patients and methods: Forty-two patients were treated with CRT between April 2004 and March 2014. Definitive radiotherapy was delivered up to a total dose of 60–70 Gy. The patients received 2 courses of S-1 (60–100 mg/day) for 2 weeks followed by 2 weeks of rest while receiving radiotherapy.
Results: Nine patients with stage I or II were treated with CRT alone. Patients with stage III or IV were treated with either induction chemotherapy (IC) with docetaxel, cisplatin, and fluorouracil (TPF) following CRT with S-1 (n=26) or CRT with S-1 alone (n=7). Of these, 92.9% completed the full CRT course. The overall complete response rate was 76.2% (CR: 32, PR: 7). The five-year disease-specific survival rates (DSS) for stages I and II were 100%, and for stages III and IV were 55.1%/58.3% (oropharyngeal/hypopharyngeal). The five-year DSS for patients with stage III or IV who had radical surgery during the same period was 64.6% (n=24). No significant differences were noted in the results between the survival outcomes of CRT (with or without IC) and surgery. Grade 3 and 4 oral mucositis frequently occurred during the CRT regardless of CRT alone or CRT followed IC. However, there was no treatment-related death, and all patients, with the exception of one, received the full radiotherapy.
Conclusion: CRT with S-1 appeared to be a well-tolerated and acceptable regimen even in combination with TPF IC.
