Comparison of autologous hematopoietic cell transplantation performed in tandem and in disease relapse in multiple myeloma patients.

Multiple myeloma is a malignant hemato-oncological malignancy that affects up to 600 people in the Czech Republic every year. Treatment options are under constant improvement and the autologous hematopoietic cell transplantation (Tx) remains a part of treatment protocols. Despite modern drug administration, the autologous Tx keeps its irreplaceable position and when ensuring two autologous Tx, the studies confirm a survival time more than twice as long as in non-transplant patients. However, there are no standardized procedures specifying the period in between the transplantations in more detail. Within our group, we compared the total of 66 patients who were administered a double transplant. One group underwent both planned tandem autologous Tx within a median of six months and mostly achieved just partial remission (PR) and less after the first transplant and out of disease progression. The other group only underwent the second Tx within a median of up to 14 months during a progression period or disease relapse. Both groups were comparable as far as basic parameters are concerned (age, type of induction therapy and cytogenetic risk). A significantly better treatment free survival (TFX) and overall survival (OS) were observed in the group where tandem Tx was administered. TFS was 18 months and median OS was not reached for the group of patients who received tandem Tx, while TFS was 10 months (p=0.04) and median OS was 57 months (p=0.005) for those who received delayed second Tx. In the group of patients who received second Tx during relapse, we observed that TFS and OS were shorter in those with a higher paraprotein level, thus suggesting the potential role of paraprotein level as a prognostic marker. The TFS in the subgroup with a high initial level was 4 months vs. 11 months (p=0.0016) and OS 44 months vs. 65 months (p=0.03).