title: Early lymphocyte recovery as a predictor of outcome, including relapse, after hematopoietic stem cell transplantation.
abstract: BACKGROUND
  Despite advances in the treatment of acute leukemia, many patients need to undergo hematopoietic stem cell transplantation. Recent studies show that early lymphocyte recovery may be a predictor of relapse and survival in these patients.
  
  
  OBJECTIVE
  To analyze the influence of lymphocyte recovery on Days +30 and +100 post-transplant on the occurrence of relapse and survival.
  
  
  METHODS
  A descriptive, retrospective study was performed of 137 under 21-year-old patients who we resubmitted to hematopoietic stem cell transplantation for acute leukemia between 1995 and 2008. A lymphocyte count < 0.3 x 10(9)/L on Day +30 post-transplant was considered to be inadequate lymphocyte recovery and counts ≥ 0.3 x 10(9)/L were considered adequate. Lymphocyte recovery was also analyzed on Day +100 with < 0.75 x 10(9)/Land ≤ 0.75 x 10(9)/L being considered inadequate and adequate lymphocyte recovery, respectively.
  
  
  RESULTS
  There was no significant difference in the occurrence of relapse between patients with inadequate and adequate lymphocyte recovery on Day +30 post-transplant. However, the transplant-related mortality was significantly higher in patients with inadequate recovery on Day +30. Patients with inadequate lymphocyte recovery on Day +30 had worse overall survival and relapse-free survival than patients with adequate recovery. There was no significant difference in the occurrence of infections and acute or chronic graft-versus-host disease. Patients with inadequate lymphocyte recovery on Day +100 had worse overall survival and relapse-free survival and a higher cumulative incidence of relapse.
  
  
  CONCLUSIONS
  The evaluation of lymphocyte recovery on Day +30 is not a good predictor of relapse after transplant however patients with inadequate lymphocyte recovery had worse overall survival and relapse-free survival. Inadequate lymphocyte recovery on Day +100 is correlated with higher cumulative relapse as well as lower overall survival and relapse-free survival.
authors: Universidade Federal do Paraná - UFPR, Curitiba, PR, Brazil.
authors: Juliane
authors: J
authors: Morando
authors: Sérgio Costa
authors: SC
authors: Fortier
authors: Ricardo
authors: R
authors: Pasquini
authors: José
authors: J
authors: Zanis Neto
authors: Carmem Maria Sales
authors: CM
authors: Bonfim
keywords: Hematopoietic stem cell transplantation; Leukemia; Lymphocyte count