Platinum/Oral Etoposide Therapy in Non-Small Cell Lung Cancer

Encouraging response rates have been observed with long-term daily administration of oral etoposide to treat lung cancer. Reasons why EP (etoposide/ cisplatin) has been used to treat non-small cell lung cancer (NSCLC), despite the fact that etoposide has demonstrated only a modest degree of activity against this disease, are preclinical suggestions of cisplatin/etoposide synergism and successful results for the combination in treating small cell lung cancer (SCLC). We evaluated a long-term daily oral etoposide regimen in combination with cisplatin for NSCLC. One course consisted of cisplatin on day 1 and etoposide from day 1 through day 21. The course was repeated, beginning at day 29. We concluded that the maximum tolerated dose in this schedule was 50 mg/m2/day oral etoposide for 21 days plus 80 mg/m2 intravenous (i.v.) cisplatin on day 1. The major dose-limiting toxic effect was myelosuppression, and mucositis was also significant in some patients. During this phase I study of 22 patients (18 evaluable), we observed partial responses (PRs) in 4 patients, 1 each with uterine cancer and SCLC, and 2 with squamous cell lung cancers. We then designed a phase II pilot study in patient