Early lymphocyte recovery predicts superior survival after autologous hematopoietic stem cell transplantation in multiple myeloma or non-Hodgkin lymphoma.

Autologous stem cell transplantation (ASCT) improves survival in patients with previously untreated multiple myeloma (MM) and relapsed, chemotherapy-sensitive, aggressive non-Hodgkin lymphoma (NHL). Lower relapse rates seen in allogeneic stem cell transplantation have been related to early absolute lymphocyte count (ALC) recovery as a manifestation of early graft-verus-tumor effect. In ASCT, the relation between ALC recovery and clinical outcomes in MM and NHL was not previously described. This is a retrospective study of patients with MM and NHL who underwent ASCT at the Mayo Clinic between 1987 and 1999. The ALC threshold was determined at 500 cells/microL on day 15 after ASCT. The study identified 126 patients with MM and 104 patients with NHL. The median overall survival (OS) and progression-free survival (PFS) times for patients with MM were significantly longer in patients with an ALC of 500 cells/microL or more than patients with an ALC of fewer than 500 cells/microL (33 vs 12 months, P <.0001; 16 vs 8 months, P <.0003, respectively). For patients with NHL, the median OS and PFS times were significantly longer in patients with an ALC of 500 cells/microL or more versus those with fewer than 500 cells/microL (not reached vs 6 months, P <.0001; not reached vs 4 months, P <.0001, respectively). Multivariate analysis demonstrated day 15 ALC to be an independent prognostic indicator for OS and PFS rates for both groups of patients. In conclusion, ALC is correlated with clinical outcome and requires further study. (Blood. 2001;98:579-585)