[Severe advanced lower gingival carcinoma effectively reduced by chemoradiation with S-1--report of a case].

Severe advanced head and neck carcinoma which can not be removed via surgical procedure combined with a large lymph node metastasis has a poor prognosis. We administered concurrent chemoradiotherapy with S-1 for a lower gingival carcinoma. As a direct result, we discovered that the treatment greatly reduced the size of tumor, and we consider that this treatment prolonged the patient.s life. The treatment results suggest that the so-called dormancy state of the tumor was continued. In this case study, radiotherapy with S-1 showed a highly effective response from the viewpoint of QOL improvement.