Purpose: To study the toxicity of high dose chemotherapy (HDCT) in multiple myeloma (MM) patients and its impact on event free survival (EFS) and overall survival (OS), and also the impact of thalidomide maintenance therapy on EFS and OS after HDCT.
Patients and methods: From April 1999 to November 2006 37 patients (29 males, 8 females) out of a total of 38 scheduled were treated with HDCT and autologous peripheral stem cell transplantation (APSCT), as consolidation treatment after first- or second-line chemotherapy. Their median age was 55 years (range 38-71). HDCT regimen used was melphalan 200 mg/m(2). Following HDCT thalidomide 100 mg/day was administered as maintenance therapy to 28 patients in a random fashion.
Results: All patients tolerated well HDCT and APSCT. There was no treatment-related mortality. The median time interval for neutrophil recovery (>500/mm(3)) was 10 days (range 8-20), while the median time interval for platelets to recover to >20.000/mm(3) was 14 days (range 9-32). Twenty (54%) patients achieved complete response (CR), 15 (40%) partial response (PR), and 2 (6%) stable disease (SD). Before receiving thalidomide as maintenance treatment 12 (42%) patients were in CR, while all the others, except one who had progressive disease (PD), were in PR. CR correlated with better EFS and probably OS. Thalidomide maintenance treatment correlated with better EFS.
Conclusion: In our series of patients HDCT appears to be a totally feasible, safe and without treatment-related mortality procedure, even in patients older than 60 years of age. It has a major impact in terms of CR achievement, which seems to strongly correlate with a prolonged EFS and OS. The use of thalidomide as a maintenance therapy induces a greater EFS which could possibly yield an improved OS.