Thalidomide based therapy for multiple myeloma (MM) improves the response and the complete remission (CR) rates in previously untreated and relapsed/refractory MM (overall response rate was 48- 73% with a 5- 10% CR) [
1,
2]. In this study, we performed a retrospective study of 42 newly diagnosed and relapsed/refractory MM patients treated with thalidomide based regimens without upfront ASCT at Ramathibodi Hospital during January 2005-October 2008. Thirteen and 29 patients were previously untreated and relapsed/refractory MM, respectively (Table
1). Twenty-two patients received thalidomide 200 mg/day and oral dexamethasone 20- 40 mg/day (d1-4) every 2 weeks, 16 patients received oral melphalan 4 mg/m
2/day (d1-7), prednisolone 40 mg/m
2/day (d1-7) and thalidomide 100 mg/day every 4 weeks, 3 patients received thalidomide 200-400 mg/day and the remaining 1 patient received thalidomide 100 mg/day, pegylated liposomal doxorubicin i.v. 40 mg/m
2/day (d1) and oral dexamethasone 40 mg/day (d1-4, 9-12) every 4 weeks. Eighty-eight percents (23/26 patients) achieving CR/VGPR (very good partial remission) received thalidomide maintenance therapy (100-200 mg/day). Aspirin 65- 325 mg/day or warfarin 1.5 mg/day was given to all patients for deep vein thrombosis prophylaxis. Of the 41 evaluable patients, median treatment period was 21 months (3- 45 m). The ORR (overall response rate) was 92.7%, with a 63.4% CR/VGPR. Median number of courses to achieve PR and CR/VGPR were 4 (range, 2-13) and 6 courses (range, 2-16), respectively. There was no difference in ORR and CR between frontline and salvage therapy groups (92.3% vs 93%) and (39% vs 23%), respectively. The ORR and CR rate for those treated with thal/dex were slightly higher than those treated with MPT (95.2% vs 87.5% and 38% vs 25%). Median follow up was 23 months, 3-year-OS and 3-year-PFS were 72.6 and 58.6%, respectively. Median TTP was 42 months, non- VGPR/CR patients had significant poorer PFS by multivariate analysis (
p = 0.01) and non-responders had significant shorter OS (
p = 0.01). In maintenance group, median treatment duration was 14 months (4-37 m). Three-year-PFS and 3-year-OS were 67 and 80%, respectively. Toxicities were constipation (81%), neuropathy (67%), muscle weakness in the legs (5%), infection (7%) and thrombosis (5%). New agents for treatment of MM with no planned ASCT show the CR/VGPR rates of 50- 80% with a PFS of 2 years [
3‐
5]. The CR/VGPR rates in our patients were also high that might be associated with a prolonged use of thalidomide induction. Thalidomide maintenance in CR/VGPR patients provided impressive survival benefit. Hence, thalidomide is an effective therapy for MM and prolonged thalidomide use had the survival benefit and had minimal serious toxicity in non-transplant MM patients. To date, MM remains incurable. Novel agents continue to be developed and are eagerly awaited [
5‐
7].
Table 1
Patients' characteristics and treatment outcomes of previously untreated and relapsed/refractory multiple myeloma
Age (years), median (range) | 62,(36-75) | | | | | | | | | | |
≤ 60 | 17 | 15(94) | 0.83 | 9(56.3) | 0.45 | 2.95 | 0.98-8.81 | 0.05 | 0.81 | 0.09-7.27 | 0.85 |
> 60 | 25 | 23(92) | | 17(68) | | | | | | | |
Sex | | | | | | | | | | | |
Male | 21 | 18(85.7) | 0.79 | 13(65) | 0.91 | 0.77 | 0.25-2.38 | 0.65 | 2.06 | 0.34-12.68 | 0.44 |
Female | 21 | 20(95.2) | | 14(66.7) | | | | | | | |
Prior treatment | | | | | | | | | | | |
Yes | 29 | 26(92.6) | 0.95 | 19(67.9) | 0.69 | 3.68 | 0.91-10.28 | 0.06 | 0.87 | 0.96-7.88 | 0.9 |
No | 13 | 12(92.3) | | 8(61.5) | | | | | | | |
International staging system | | | | | | | | | | | |
I, II | 8, 18 | 24(92.3) | 0.97 | 15(57.7) | 0.93 | 6.30 | 0.73-54.01 | 0.09 | 2.22 | 0.20-24.57 | 0.51 |
III | 13 | 12(92.3) | | 8(61.5) | | | | | | | |
No data | 3 | | | | | | | | | | |
M-protein subtype | | | | | | | | | | | |
IgG, IgA, IgM | 23, 8, 1 | 27(87.1) | 0.32 | 19(61.3) | 0.86 | 3.19 | 0.64-15.91 | 0.16 | 1.21 | 0.13-11.65 | 0.87 |
Kappa, Lamda | 3, 6 | 9(100) | | 6(66.7) | | | | | | | |
Unknown type | 1 | | | | | | | | | | |
Serum creatinine level | | | | | | | | | | | |
< 2 mg/dl | 34 | 31(91.2) | 0.43 | 22(64.7) | 0.57 | 0.74 | 0.08-6.72 | 0.79 | 0.03 | 0.01-856.9 | 0.50 |
≥ 2 mg/dl | 8 | 7(100) | | 4(57.2) | | | | | | | |
Serum β2 M level, μg/ml | | | | | | | | | | | |
≤ 5 | 26 | 24(92.3) | 0.53 | 17(65.4) | 0.79 | 4.89 | 0.55-43.88 | 0.16 | 1.97 | 0.18-21.81 | 0.58 |
> 5 | 13 | 11(84.6) | | 8(61.5) | | | | | | | |
No data | 3 | | | | | | | | | | |
Response to treatment | | | | | | | | | | | |
Yes | 38 | - | - | - | - | 0.15 | 0.04-0.61 | 0.01 | 0.03 | 0.01-0.35 | 0.01 |
No | 3 | | | | | | | | | | |
CR/VGPR | | | | | | | | | | | |
Yes | 26 | - | - | - | - | 0.14 | 0.04-0.47 | 0.01 | 0.21 | 0.03-1.48 | 0.12 |
No | 15 | | | | | | | | | | |