Etoposide: seeking the best dose and schedule.

Etoposide is an important antineoplastic drug. Despite the use of several combination chemotherapy regimens that include etoposide, the best dose and schedule for etoposide remains unknown. The schedule dependency for small cell lung cancer is now known, and it is likely the same for other sensitive neoplasms (ie, lymphoma, germ cell tumors). Recent data suggest that even a more extended schedule of administration (ie, 14 to 21 days) may be more effective than the standard 3- to 5-day schedule. Several studies have assessed plasma levels in reference to dose, schedule, and tumor responsiveness. Preliminary data suggest that high peak levels (ie, > 5 to 10 micrograms/mL) are associated with more severe myelosuppression than lower peak plasma levels (ie, 1 to 3 micrograms/mL). Response rates and survival in small cell lung cancer patients given low daily doses for 14 to 21 days are comparable with results achieved with standard doses given for 3 to 5 days. Preliminary data from several studies suggest that administering low doses for a prolonged schedule is a superior method of etoposide administration. Other studies including randomized comparisons are necessary to confirm these observations.