Activity of decitabine as maintenance therapy in core binding factor acute myeloid leukemia.

Abstract

7522 Background: Real-time quantitative (RTPCR) based minimal residual disease (MRD) monitoring provides prognostic information in core binding factor acute myeloid leukemia (CBF-AML). Earlier we reported on the activity of decitabine (DAC) as maintenance therapy in a smaller cohort of patients with CBF AML. Methods: We have summarized the results in patients (pts) with CBF who received DAC maintenance for persistent RTPCR positivity or because of inability to complete all planned consolidation in a fludarabine, GCSF, cytarabine (FLAG) based regimen. The planned number of DAC cycles was 12 but could be adjusted at the discretion of the treating physician based on RTPCR response. Serial RTPCR was obtained approximately every 2-3 months. Results: Thirty-four pts with CBF-AML [t(8;21)=14 and inv(16)=20] received DAC as maintenance. Eighteen pts (53%) completed a full course (7 cycles) of FLAG based regimen before DAC for persistent PCR positivity (group 1). Sixteen pts (47%) were switched to DAC as they did not complete planned consolidation (group 2). In group 2, 9 pts (56%) had negative PCR (group 2A) and 7 pts (46%) had positive PCR (group 2B) prior to starting DAC. Patient characteristics are summarized in table. The median follow up was 59.2 [15.4-107.2] and 32.47 [8.5-86.3] months for group 1 and 2, respectively. In Group 1 and group 2A only 1 patient each had relapse, while 5 pts (72%) from group 2B had relapse. All the patients in group 2B with relapse were at suboptimal RTPCR response (>0.1%). Conclusions: Our study shows DAC is an effective maintenance for CBF-AML pts who have persistent PCR positively after FLAG based induction consolidation and those unable to tolerate a full course, but have negative PCR. However patients with high levels of MRD persistence should be considered for stem cell transplant. [Table: see text]