Primary Chemotherapy of Multiple Myeloma with Cyclophosphamide and High Dose Dexamethasone

초록

With advent of high-dose therapy rescued by bone marrow transplant (BMT), melphalan and prednisone are not being used as the primary therapy for multiple myeloma. Lack of stem cell damage provides an advantage in using vincristine, adriamycin, and dexamethasone (VAD) for initial cytoreduction before stem cell mobilization and BMT. However, the use of VAD therapy does not go without toxicity, and elderly people often cannot tolerate the adverse effect. 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. From August 1996 through June 2003, 22 chemotherapy-naive patients entered the clinical trial. The chemotherapy cnsisted of 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. Fourteen of 22 showed response (64%) with CR in 8 (36%). The time to CR ranged 3-8 months (median 7), and to 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).