Infused peripheral blood autograft absolute lymphocyte count correlates with day 15 absolute lymphocyte count and clinical outcome after autologous peripheral hematopoietic stem cell transplantation in non-Hodgkin's lymphoma.

ABSTRACT

Absolute lymphocyte count at day 15 (ALC-15) after autologous peripheral blood hematopoietic stem cell transplantation (APHSCT) is an independent prognostic factor for survival in non-Hodgkin's lymphoma (NHL). Factors affecting ALC-15 remain unknown. We hypothesized that dose of infused autograft lymphocytes (A-ALC) directly impacts upon ALC-15. A total of 190 consecutive NHL patients received A-ALC between 1993 and 2001. The primary end point was correlation between A-ALC and ALC-15. A strong correlation was identified (r=0.71). A higher A-ALC was infused into patients achieving an ALC-15 > or =500/microl vs ALC-15 <500/microl (median of 0.68 x 10(9)/kg (0.04-2.21 x 10(9)/kg), vs 0.34 x 10(9)/kg (0.04-1.42 x 10(9)/kg), P<0.0001). The median follow-up for all patients was 36 months (maximum of 109 months). The A-ALC threshold was determined at 0.5 x 10(9)/kg. The median overall survival (OS) and progression-free survival (PFS) times were longer in patients who received an A-ALC >/=0.5 x 10(9)/kg vs A-ALC <0.5 x 10(9)/kg (76 vs 17 months, P<0.0001; 49 vs 10 months, P<0.0001, respectively). Multivariate analysis demonstrated A-ALC to be an independent prognostic indicator for OS and PFS. These data support our hypothesis that ALC-15 and survival are dependent upon the dose of infused A-ALC in NHL.