The oral anticancer agent TS-1 has the advantage of being able to be administered daily, while monitoring the grade of adverse events. Therefore, we used concurrent chemoradiotherapy with TS-1 to treat advanced oral squamous cell carcinomas（OSCCs）in elderly patients with complications. Here, we report feasibility, problems, and counter measures for such patients.
The subjects were 8 elderly patients with Stage Ⅲ and Ⅳ OSCCs, ranging in age from 68 to 82 years（mean 75.8 years）. Each patient had 3 complications on average, and cardiovascular diseases accounted for 33.3 ％ of all complications. There were 5 primary cases and 3 recurrent cases.
Radiotherapy（2.0 Gy/fraction/day; 5 days/week）was given to a total dose between 60 and 66 Gy, except in a patient with recurrence in whom the dose was reduced to 50 Gy because of previous radiotherapy. Although the recommended dose of TS-1 was 65 mg/m2/day, the dose was adjusted between 47.5 and 69.1 mg/m2/day according to age and general condition. Oral administration of TS-1 for 2 weeks followed by 1-week rest period comprised one course. Two courses with concurrent radiotherapy were administered.
Chemoradiotherapy was performed as scheduled in 6 patients. In 2 patients, the administration of TS-1 was interrupted during the second course because of grade 3 leukopenia, but the radiotherapy could be completed. The overall response rate（6 CRs, 1 PR, and 1 death from another disease）was 87.5 ％. After a median follow-up of 12.8 months（range 2.2-40.9 months）, 6 patients were alive, and 5 patients had no evidence of disease. We could administer TS-1 safely while monitoring the grade of adverse events. However, all patients had grade 3 dermatitis or mucositis, and grade 3 leukopenia and anemia occurred in 2 patients each. One of the causes of these adverse events was suspected to be a high plasma concentration of 5-fluorouracil（5-FU）due to reduced renal function.
Our results indicate that this therapy may be feasible for elderly patients with advanced oral cancer and complications and become a curative treatment considering QOL in some patients. However, severe dermatitis and mucositis must be carefully treated in these patients.
