Determining the optimal time for bortezomib-based induction chemotherapy followed by autologous hematopoietic stem cell transplant in the treatment of multiple myeloma.

In our study, we determined the efficacy of bortezomib-based induction therapy followed by autologous stem cell transplant (ASCT) in newly diagnosed and relapsed/refractory (R/R) multiple myeloma (MM) patients and compared the advantages of early versus late transplant. We used a retrospective analysis to examine 62 patients, including 46 cases of newly diagnosed MM (early transplant group) and 16 cases of relapsed/refractory MM (late transplant group). All of these patients received bortezomib-based induction therapy followed by ASCT. The efficacy and side effects of the treatment regimen were analyzed. Patients' overall survival (OS) and progression-free survival (PFS) times were determined. The ratio of complete remission to near-complete remission (CR/nCR) was 69.5% versus 56.2% (P=0.361), respectively, for the early transplant group versus the late transplant group, respectively, after receiving bortezomib-based induction therapy; the overall response rates of the two group were 91.3% and 81.2%, respectively (P=0.369). After receiving ASCT, the CR/nCR of the two groups increased to 84.8% and 81.3%, respectively. The median time required for neutrophil engraftment of the early transplant group and the late transplant group was 11 and 14.5 days, respectively (P=0.003); the median time required for platelet engraftment was 13 and 21.5 days (P=0.031), respectively. There were no significant differences in the toxic side effects observed during induction therapy and ASCT between the two groups. The OS of the two groups was not statistically different (P=0.058). The PFS of the early transplant group and the late transplant group was 41.6 and 26.5 months, respectively (P=0.008). Multivariate analysis demonstrated that the time of receiving ASCT, the types of M protein, and the International Staging System (ISS) stage were all independent factors that influenced PFS. In conclusion, patients in a suitable condition for ASCT should be recommended to have an early ASCT immediately after diagnosis.