Etoposide: twenty years later.

Since the beginning of its clinical development 20 years ago, etoposide has become an important and widely used agent in clinical oncology. Its integral role in the treatment of germ cell tumors and small-cell lung cancer seems unlikely to diminish in the future, and its use in non-Hodgkin's lymphoma and in various high dose regimens will probably continue to increase. Active investigation continues regarding the optimal dose and schedule of etoposide, and it is likely that these investigations will result in further improvement of its clinical activity in patients with sensitive tumor types. Continued clinical investigation may result in the identification of active etoposide containing combination regimens for ovarian cancer, breast cancer, and some of the childhood malignancies. Exciting possibilities for the future include exploration of etoposide in combination with the topoisomerase I inhibitors, as well as the development of drugs to reverse drug resistance. During the next 10 years, the applications and importance of this unique drug will continue to increase.