Long-term prognostic significance of response in multiple myeloma after stem cell transplantation

Abstract

For establishing the true effect of different response categories in patients with multiple myeloma (MM) treated with autologous stem cell transplantation, we evaluated, after a median follow-up of 153 months, 344 patients with MM who received a transplant between 1989 and 1998. Overall survival (OS) at 12 years was 35% in complete response (CR) patients, 22% in near complete response (nCR), 16% in very good partial response (VGPR), and 16% in partial response (PR) groups. Significant differences in OS and progression-free survival were found between CR and nCR groups (P = .01 and P = .002, respectively), between CR and VGPR groups (P = .0001 and P = .003), or between CR and PR groups (P = .003 and P = < 10(-5)); no differences were observed between the nCR and VGPR groups (P = .2 and P = .9) or between these groups and the PR group (P = .1 and P = .8). A landmark study found a plateau phase in OS after 11 years; 35% patients in the CR group and 11% in the nCR+VGPR+PR group are alive at 17 years; 2 cases had relapsed in the nCR+VGPR+PR group. In conclusion, MM achieving CR after autologous stem cell transplantation is a central prognostic factor. The relapse rate is low in patients with > 11 years of follow-up, possibly signifying a cure for patients in CR.