Non-myeloablative HSCT in elderly AML/MDS patients in 1st CR

Abstract

6655 Background: Reduced intensity allogeneic transplant (“minitransplant ”) may extend the age limit beyond which patients with AML in first CR can receive a transplant. However, until now, the feasibility of minitranplant has not been explored. Methods: From 2001–2003, all pts age >50 admitted to the Leukemia Service with AML or high-risk MDS (10- 29% blasts) and cytogenetic abnormalities other than inv (16), t(8;21) or t(15;17) were to receive a transplant consult with the intent of performing a minitransplant in 1st CR if a sibling or unrelated donor could be found. Herein we describe the effectiveness of this program, focusing on 99 pts who entered CR (CR rate 39%). Results: 62 of the 99 pts received a transplant consult. 68% of the remaining 37 pts were felt to be poor candidates for transplant and were not referred for consult, 16% refused, and in 16% logistical factors (e.g. insurance approval) prevented consultation. Donors were identified for 25 of the 62 consulted pts (20 siblings, 5 unrelated). 18 pts were transplanted (14 in 1st CR; 4 in 1st relapse). Time from CR to transplant ranged from 1 to 32 weeks (median 11). We divided the 99 pts into 4 groups: Pts who received a consult were younger than those who did not (p = .01); among consulted pts, those with a donor were younger than those without (p = .03). Transplanted pts were younger than non-transplanted pts (p= .01) and less likely to have unfavorable (-5, -7) cytogenetics (p = .02); among pts without unfavorable cytogenetics, similar proportions of transplanted (67%) and non-transplanted pts (58%) had an antecedent hematologic disorder or 2ndary AML/MDS. Relapse-free survival was significantly longer in the transplant group (P=0.03). Discussion: The superior RFS in transplanted pts may be due to their younger age, better cytogenetics, or unknown selection factors, as well as to the efficacy of the transplant. Even with a systematic plan in place, the procedure is available in 1st CR to only 14% of older pts with cytogenetic abnormalities. No significant financial relationships to disclose.