Klin Onkol 2002; 15(Suppl 2002): 31-35.
Summary:
Background: High doses of chemotherapy followed by autologous transplantation has become widespreadly indicated as upfront therapy for patients with multiple myeloma (MM) during last decade, with very good tolerance and low mortality (2-3%). Therapy of relapsing MM is still considered experimental.
Design of study: The principle of T2 model is repeated transplantation therapy with testing different experimental approaches in patients with MM relapsing/progressing after the 1st autologous transplantation (AT). The patients (pts) are treated with 3the same + something more3 same or very similar induction and reinduction treatment, same myeloablative regimen in the first and the second transplantation and a different maintenance, experimental therapy after the 2nd transplantation. The evaluation of the results of each therapeutic approach uses intra-individual analysis – the comparison of event free survival I (EFS I) (after the 1st AT) and EFS II (after the 2nd transplantation) in one patient. In T2 model is EFS I and EFS II compared in one patient, therefore the inter-individual differences are excluded.
Subjects: 20 pts with relapsing/progressing MM after the 1st AT were included in the pilot study between January 1997 and May 2001.
Methods and results: Pts were matched to the following groups of experimental therapy: autologous transplantation with IL-2 activated PBSC-10 pts (50%), pamidronate– 4 pts (20%), mini-allogeneic transplantation –2 pts (10%), thalidomide –3pts (15%), consolidation chemotherapy CED1 pt (5%). A sensitivity to reinduction chemotherapy C-VAD (4x) was more than 90%, the response to the 2nd transplantation acording to the 1st one was in 45 % better (9 pts), in 35% same (7 pts) and in 20 % worse (4 pts). The toxicity of the 1st and second transplantation was similar and usually did not exceed gr. II (SWOG criteria), there were no significant differences instead of clinically irrelevant hematotoxicity. Transplant-related mortality was 5% (1/20). In 15 pts MM had relapsed till 31st May 2001 (15/20). 5 pts have achieved prolongation of EFS II vs EFS I, 2 in IL-2 activated graft group, 1 in pamidronate group and 2 in allogeneic transplantation. Completed data from the analysis of the first – IL-2 group are listed here, in 20% pts (2/10) was EFS II > EFS I, curative effect was not confirmed. In the whole group median of EFS I was 15,2 months, median of EFS II was 9,9 months, median of overall survival (OS) was 62,8 months, 95% (19/20) were allive (till 31st May 2001).
Conclusions: Repeated transplantation is one of the most powerful approaches in treatment of relapsing MM; toxicity is acceptable, also engraftment is similar to the 1st AT. Testing of new perspective approaches by T2 model may bring a fundamental benefit, although our first results were negative.
