Abstract
Patients(pts) who undergo autologous stem cell transplant (ASCT) for multiple myeloma (MM) are routinely assessed at Day-100 using serum monoclonal protein (M-spike), free light chains(FLC), and urine studies. Limited data are available to assess the prognostic value of an increasing M-spike or FLC from immediately before ASCT to Day-100 post-ASCT. We evaluated this in our cohort of patients.
We retrospectively reviewed 1070 pts with MM at Mayo Clinic, Rochester, who had their first ASCT between 2000 and 2016. We stratified pts according to a rise in M-spike by at least >0.1g/dl from immediately before ASCT to Day-100 post-ASCT (cohort 1) compared to those who did not (cohort 2). We also stratified pts according to a rise in involved FLC by at least >5mg/dl (cohort 3) compared to those who did not (cohort 4). Survival analysis for progression free survival (PFS) and overall survival (OS) was performed using the Kaplan Meier method.
46 pts were found to have a rise in M-spike by at least >0.1g/dl between pre-ASCT and Day-100 (cohort 1) and 825 pts were found to have a declining or <=0.1g/dl increase in M-spike (cohort 2). 25 pts were found to have an increase in involved FLC by at least >5mg/dl (cohort 3) and 1045 pts were found to have a decrease or a < = 5mg/dl increase in involved FLC (cohort 4). The median PFS was significantly shorter in cohort 1 compared to cohort 2 (median PFS of 10 months vs. 27 months, respectively P<0.0001). Cohort 1 patients also had an inferior OS, compared to cohort 2 (median OS of 34 months vs. 79 months, respectively, P<0.0001). Similarly the median PFS and OS were found to be inferior in cohort 3 compared to cohort 4 (median PFS of 4 months and 28 months, respectively p<0.0001 and median OS of 11 months and 82 months, respectively, p<0.0001)
An increase of M-spike by at least >0.1 g/dl and involved FLC by at least >5mg/dl from pre-ASCT to Day-100 is predictive of inferior PFS and OS in pts with MM. These patients would benefit from closer surveillance post Day-100.