Results from a phase II clinical trial suggest that combining the cancer drug S-1 (Teysuno) with the chemotherapy agent cisplatin (Platinol) and radiation therapy may be effective in non-small cell lung cancer (NSCLC). Patients with inoperable, locally advanced NSCLC were treated with S-1, Platinol, and radiation to the chest region. Tumors shrank at least 30% in 36 out of 41 patients. Although some patients experienced low levels of white blood cells, overall the treatment was well tolerated. S-1 is itself a combination of tegafur (a chemotherapy agent), gimeracil (which boosts tegafur levels in the body), and oteracil (which protects the stomach and gut from tegafur toxicity.