Disease response and survival outcomes in acute myeloid leukemia (AML) patients unfit for chemotherapy treated with 10-day decitabine as initial therapy.

Abstract

6611 Background: AML is primarily a disease of older adults, with a median age of 67 years at diagnosis. Many patients are considered unfit for chemotherapy due to poor performance status and/or comorbidities, prompting investigation of less intensive approaches. A clinical trial in which 10-day courses of decitabine 20mg/m2 were given every 28 days as initial therapy demonstrated a promising complete remission (CR) rate and disease-free survival (DFS). We used this regimen to treat AML patients unfit for chemotherapy outside of a clinical trial. Methods: Charts of 32 newly diagnosed AML patients treated with 10-day courses of decitabine 20mg/m2 as initial therapy at the University of Maryland Greenebaum Cancer Center between September 2010 and November 2011 were retrospectively reviewed. If patients attained bone marrow blasts <5%, 5-day courses were administered subsequently and were continued until disease progression. Results: Median age at diagnosis was 74 years (range, 52-86). 18 patients were male and 14 female. 23 were Caucasian, 7 African-American and 1 Hispanic. 10 patients (31%) had performance status ≥ 2. All had significant cardiac, pulmonary and/or renal disease. Karyotype risk group was unfavorable in 17 patients, intermediate in 14 and unknown in one. There were 9 CRs and 1 partial remission, for an overall response rate of 31%, following a median of 2 (range, 1 to 4) courses. 21 patients did not respond to treatment following 1 to 6 courses, and one died within 29 days of treatment initiation. 21 patients (65%) were hospitalized at least once for fever or infection during treatment. Of the 9 patients who achieved CR, 5 had normal, 3 complex and 1 unknown karyotypes. Median DFS was 390 days (range, 87+-468+) and median OS 180 days (range, 15-623+). Six-month OS was 37.5% and 1-year OS 16.5%. Conclusions: AML patients unfit for chemotherapy treated with 10-day decitabine 20mg/m2 outside of a clinical trial had a higher response rate than reported for 5-day decitabine, but a lower response rate than in the reported clinical trial of the 10-day regimen. Additional novel treatment approaches are needed for these patients.