Etoposide, dexamethasone, cytarabine, and cisplatin in vincristine, doxorubicin, and dexamethasone-refractory myeloma.

Based on remarkable activity in refractory lymphomas, a combination of etoposide, cisplatin (both administered by 4-day continuous infusions), cytarabine (Ara-C), and dexamethasone (EDAP) was evaluated in 20 patients with advanced myeloma refractory to standard melphalan and prednisone (MP) and/or vincristine, Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), and dexamethasone (VAD) and even to high doses of melphalan (HDM) (seven patients). Forty percent of patients responded regardless of previously recognized risk factors (eg, duration of drug resistance, tumor mass, and serum lactic dehydrogenase [LDH] level). While the median survival was only 4.5 months, patients with good performance (Zubrod less than 2) and low or intermediate tumor stage survived more than 14 months compared with only 2 months for the remaining group. EDAP could be readily administered in the outpatient clinic, but neutropenic fever prompted hospital admission in 80% of patients, half of whom developed penumonia and sepsis, a fatal outcome in four patients. Severe myelosuppression was of short duration, so that subsequent cycles could be administered every 3 to 4 weeks. No serious extramedullary toxicity, including renal toxicity, was encountered. Marrow toxicity and hence infectious complications may be reduced by elimination of Ara-C without compromising treatment efficacy. We conclude that the lack of cross-resistance with VAD and even HDM makes EDAP or a similar combination an attractive regiment to be formally explored in an alternating sequence with VAD in high-risk myeloma.