Chemotherapy of Multiple Myeloma using Cyclophosphamide and High Dose Dexamethasone

초록

High-dose dexamethasone monotherapy given in doses similar to the VAD regimen has shown response rates almost similar to those observed with VAD in primary refractory myeloma. Cyclophosphamide, an active agent in the treatment of multiple myeloma, seldom causes stem cell damage. We opted to combine cyclosphosphamide and high dose dexamethasone as the primary treatment of multiple myeloma to see the efficacy of the regimen. 22 chemotherapy-naive patients entered the clinical trial. The chemotherapy comprised cyclophosphamide IV at a fixed dose of 400mg and dexamethasone IV at a fixed dose of 40mg, regardless of body surface, for 4 or 5 consecutive days repeated every 3 or 4 weeks. The patients consisted of 10 males and 12 females whose ages ranged 45-82 with a median of 65. Most of the patients were in Durie Salmon stage IIIA (16), and the others were in stage IA (1), IIB (1), and IIIB (4). Their performance on ECOG scale was graded as I in 8, II in 6, III in 6, and IV in 2. The cycles of the chemotherapy administered ranged 2-32 (median 10) with a total of 251. Focal radiotherapy was given as well to 5 patients during the chemotherapy for the aim of palliation. Fourteen of 22 showed response (64%) with CR in 8 (36%). The time of treatment required for CR to be attained ranged 3-8 months (median 7), and that for PR 2-8 months (median 4.5). The duration of CR ranged 5-17 months (median 9), and that of PR 1-12 months (median 4). The overall survival of all patients ranged 3+ to 50 months (median 16.5), that of patients who attained CR 12+ to 49 months (median 21.5+), that of patients once in PR 3+ to 50 months (median 24.5), and that of non-responders 4-34 months (median 10). Six of 8 complete responders (12+, 13+, 15+, 18+, 25+, 26+ months each), 1 of 6 partial responders (3+ months), and none of 8 non-responders are alive as of this writing. Four of 8 patients in CR underwent BMT (3 autologous and 1 allogeneic). Adverse effect of the chemotherapy was minimal.