Allogeneic hematopoietic stem cell transplantation as part of postremission therapy improves survival for adult patients with high-risk acute lymphoblastic leukemia - A metaanalysis

BACKGROUND. The prognosis for adult patients with acute lymphoblastic leukemia (ALL) remains unsatisfactory primarily because of the high incidence of recurrence. Therefore, optimal postremission therapy is a matter of vital concern. In particular, the clinical efficacy of allogeneic hematopoietic stem cell transplantation (HSCT) should be clarified. METHODS. Rigorous criteria were used to select 7 studies of adult ALL that prospectively assessed overall survival (OS) using natural randomization based on donor availability combined with intention-to-treat analyses. The authors then performed a metaanalysis to evaluate the role of allogeneic HSCT. RESULTS. Seven studies that included 1274 patients were selected. A metaanalysis demonstrated that patients in the donor groups had significantly better survival than patients in the no-donor groups (hazard ratio [HR], 1.29; 95% confidence interval [95% CI], 1.02-1.63 [P =.037]). When only high-risk patients were included in the analysis, the superiority of the survival advantage was even greater (HR, 1.42; 95% CI, 1.06-1.90 [P =.019]). A meta-regression analysis revealed that compliance with allogeneic HSCT showed a significant and positive correlation with survival (coefficient, 0.022; P <.01), suggesting that the greater the proportion of patients who actually received allogeneic HSCT, the better the survival of the donor group. No beneficial effects of autologous HSCT were observed. CONCLUSIONS. The current findings demonstrated that allogeneic HSCT improves the outcome of adult patients with high-risk ALL. Although these analyses were based on abstracted data, the results indicated that allogeneic HSCT should be considered for such patients if a suitable donor is available.