ALLOGENEIC OR AUTOLOGOUS STEM-CELL TRANSPLANTATION FOLLOWING SALVAGE CHEMOTHERAPY FOR ADULTS WITH REFRACTORY OR RELAPSED ACUTE LYMPHOBLASTIC-LEUKEMIA

Over a 9-year period 37 consecutive adults with primary refractory (n = 13) or first relapse of ALL (n = 24) received an intensive salvage c hemotherapy regimen with the final intention of undergoing stem cell t ransplantation (SCT). Twenty-nine patients who achieved complete remis sion (CR) were assigned to receive autologous SCT (autoSCT) or allogen eic SCT (alloSCT) based on age and availability of a histocompatible s ibling. Of the 19 patients assigned to autoSCT, 10 did not reach the t ransplant due to early relapse (n = 9) or fungal infection (n = 1), an d nine were transplanted a median of 2.5 months (1-8) from CR, eight w ith an immunologically purged graft. One patient died early from ARDS and eight relapsed 2-30 months post-SCT. Three of the 10 patients assi gned to alloSCT relapsed early, but all 10 received the assigned trans plant a median of 2.5 months (1-7) from CR. Four died from transplant- related complications 0.7-12 months post-SCT, and six are alive and di sease-free 9.7-92.6 months after the procedure. In an intention-to-tre at analysis, the mean overall survival from CR for those assigned to a utoSCT and alloSCT are 11.3 months (0.5-34.3) and 60.1 (2.3-98.3), res pectively (log-rank, P < 0.01). Only 65% of patients who reached CR an d 51% of the initial 37 cases underwent the intended SCT. We conclude that few adults with refractory or relapsed ALL actually reach SCT in CR even when the protocol used is designed for this purpose. AutoSCT a ppears to offer little benefit in this setting, and an alloSCT from a related or unrelated donor should be rapidly pursued after achieving C R.