THE ROLE OF AUTOLOGOUS STEM CELL TRANSPLANTATION AND TUMOR LOAD IN MULTIPLE MYELOMA

Background: Multiple myeloma remains an incurable disease despite the emergence of new drugs. The search of optimal therapeutic strategy to increase life expectancy and remission in patients with this disease is continues. This is facilitated to the achievement of the maximum possible response and eradication of residual tumor load. Existing recommendations for the treatment of multiple myeloma approve the use of autologous stem cell transplantation (autoSCT) to improve disease control. Aims: To determine the impact of autologous stem cell transplantation on efficiency of treatment and tumor load in patients with multiple myeloma. Methods. The study included 89 patients with MM (median age 58 years, male/female – 1.12:1). The induction therapy with Bortezomib-based regimens (VD, CVD, VMP, PAD) was used in 62/89 (69.6%) patients, Immunomodulator-based regimens (Thal+D, RD, VRD, PomD) – in 22/89 (24.8%), chemotherapy – in 4/89 (5.6%). High dose therapy (Mel200) and autoSCT is carried out in 64/89 (71.9%) patients. The efficiency of therapy was evaluated according to IMWG criteria. Tumor load was determined by multicolor flow cytometry (5-colors): 79 patients – after 4-6 courses of induction therapy, 39 patients – after autoSCT; 29 patients – tumor load was performed in dynamics (before and after autoSCT). Results. The sex, age, the variant induction antimyeloma therapy did not affect on response rate and tumor load. CR was achieved in 28/89 (31.4%) before AutoSCT and 50/89 (56.2%) after AutoSCT (p>.05). However, high dose therapy (Mel200) and AutoSCT has increased the possibility of achieving complete response in dynamics: before AutoSCT in 5/29 (17.2%), after AutoSCT – in 13/29 (44.8%) (p0.01%" and 25 months – in the group "tumor load without autoSCT >0.01%"(p=.006). Examination of tumor load in the dynamics in 29 patients showed that autoSCT reduces the level of tumor load (before autoSCT = 2.27±0.20, after autoSCT – 0.14±0.01). Tumor load <0.01% after autoSCT was detected more often than before autoSCT (14/29 and 5/29 patients, respectively) (p