Recovery of polyclonal immunoglobulin serum levels to normal levels after autologous stem cell transplantation predicts disease free survival in patients with multiple myeloma

Abstract

10088 Background: The ability of the immune system to recover its components after autologous stem cell transplantation (ASCT) is known to predict survival in patients with different types of neoplasms. Also, our previous work showed that polyclonal immunoglobulin can be used to improve T cell diversity and, consequently, T cell function in animal models. The aim of this retrospective study was to understand if the recovery of the polyclonal compartment of immunoglobulin in patients with multiple myeloma (MM) at day 100 (± 40d) after ASCT is a predictor factor for survival in MM patients who were subject to ASCT. Methods: From294 patients with IgG-MM subject to ASCT at the Mayo Clinic, Rochester, MN since October, 1993 until June, 2004, 143 patients were studied. The rational to select this group of patients was the fact that they had levels of serum IgM collected at day 100 ± 40 after ASCT recorded. Progression free survival (PFS) was assessed from the day of the transplant. PFS was studied using Kaplan-Meier curves and the univariate and multivariate analysis were done using age-adjusted proportional Cox. The prognostic variables in the multivariate model were: recovered of IgM at day 100, B2 microglobulin, age, conditioning regimen and disease status at the time of transplant. Results: There were 59 females in the study. The median age of the cohort was 58 y (33–75). The median follow up of the study was 26 mo (range, 2-111). PFS was significantly higher in the group who recovered normal serum levels of IgM at D100 compared to the pts who did not. This corresponds to a survival that is 1.5 longer in the group of patients who recovered normal levels of IgM at day100 after ASCT versus the patients who did not (median: 34 to 23 mo, respectively; p=0.05). By univariate analysis, those who did not recover normal serum levels polyclonal immunoglobulin by day 100 after ASCT had a risk of relapse 65% higher than the risk of the patients who recovered. Multivariate analysis suggests that recover the normal levels of polyclonal immunoglobulin after ASCT is an independent prognostic factor for PFS for MM patients after ASCT. Conclusions: These results suggest that polyclonal immunoglobulin is a major factor promoting immunity after ASCT. No significant financial relationships to disclose.