Second autologous transplantation for multiple myeloma patients relapsing after the first autograft -- a pilot study for the evaluation of experimental maintenance therapies. Report of the prospective non-randomized pilot study of the Czech Myeloma Group

Abstract

Background: High-dose chemotherapy followed by autologous stem cell transplantation (AT) is accepted as first-line therapy for patients with multiple myeloma (MM), with very good tolerance and low mortality (2-3%).

Study design: We tested repeated transplantation with different experimental maintenance therapies in patients with MM relapsing/progressing after first AT. Results were compared using intra-individual analyses, therefore inter-individual differences are excluded (T2 model).

Patients and methods: Between January 1997 and January 2003, 32 patients with relapsing/progressing MM after first AT were included in the pilot study, median follow-up was 75.2 months. They received the following experimental therapies: IL-2-activated PBSC (10 pts), pamidronate (4 pts), thalidomide (15 pts), consolidation chemotherapy CED (3 pts).

Results: Sensitivity to C-VAD reinduction chemotherapy (4 cycles) was 50%, response to the second AT compared to the first was better in 7, the same in 16 and worse in 9 patients. Toxicity of the first and second transplantation was similar and usually did not exceed grade II (SWOG). Transplant-related mortality was 3% (1/32). Event-free survival after second AT (EFS II) is known in 22 patients; 7 have achieved prolongation of EFS II versus EFS I. In the whole group median EFS I was 15.7 months, median EFS II was 12.9 months, median overall survival (OS) was 79.1 months; 20/32 patients were alive at the time of analysis.

Conclusions: Repeated AT is a feasible and successful strategy in treatment of relapsing MM; response to second AT and toxicity were acceptable and similar to the first AT in our assessment.