[A case of non-small cell lung cancer responding to S-1 over a year]

A 71-year-old woman was admitted to our hospital, because of an abnormality on her chest radiograph findings. After extensive examination, she was diagnosed with primary lung adenocarcinoma (cT4N2M1, stage IV). She was treated by carboplatin+gemcitabine, gefitinib and docetaxel and the responses were stable disease in any treatment. As the fourth-line treatment, she received oral chemotherapy using S-1 at 100 mg/day (80 mg/m2 day) for 28 days, followed by withdrawal for 14 days. Tumor size was reduced 29.2% after 1 course, 62.5% after 5 courses and 83.3% after 10 courses (14 months). Hematologic and non-hematologic toxicities were mild with the S-1 administration. We experienced a case of continuation of tumor shrinkage over a year without serious adverse events by S-1 treatment. Therefore, oral administration of S-1 could be useful for the treatment of recurrent non-small cell lung cancer over a long time.