Decitabine as a First-Line Treatment for Older Adults Newly Diagnosed with Acute Myeloid Leukemia

Abstract

Purpose: Decitabine, a DNA hypomethylating agent, was recently approved for use in Korea for older adults with acute myeloid leukemia (AML) who are not candidates for standard chemotherapy. This study aimed to evaluate the role of decitabine as a first-line treatment for older adults with AML.

Materials and methods: Twenty-four patients with AML who received at least one course of decitabine (20 mg/m²/d intravenously for 5 days every 4 weeks) as a first-line therapy at Severance Hospital were evaluated retrospectively.

Results: The median age of the patients was 73.5 years. The longest follow-up duration was 502 days. A total of 113 cycles of treatment were given to 24 patients, and the median number of cycles was four (range, 1-14). Thirteen patients dropped out because of death, no or loss of response, patient refusal, or transfer to another hospital. Twenty-one (87.5%) and 12 (50%) patients completed the second and fourth cycles, respectively, and responses to treatment were evaluated in 17. A complete response (CR) or CR with incomplete blood-count recovery was achieved in six (35.3%) patients, and the estimated median overall survival was 502 days. Ten patients developed grade >2 hematologic or non-hematologic toxicities. In univariate analysis, bone marrow blasts, lactate dehydrogenase, serum ferritin level, and bone marrow iron were significantly associated with response to decitabine.

Conclusion: Five-day decitabine treatment showed acceptable efficacy in older patients with AML who are unfit for conventional chemotherapy, with a CR rate 35.3% and about a median overall survival of 18 months.

Keywords: AML; Decitabine; elderly; treatment.

Fig. 1. Overall treatment responses and outcomes diagram for older patients with AML. NE, not evaluable; NR, no response; CR, complete remission; CRi, CR with incomplete blood-count recovery; PR, partial remission; LOR, loss of response; AML, acute myeloid leukemia.

Fig. 2. Boxplot of the baseline (A) serum ferritin and (B) LDH levels in patients according to the decitabine response (the responders and the non-responders). Serum ferritin and LDH levels at diagnosis were significantly lower in the responders than in the non-responders. LDH, lactic dehydrogenase.

Fig. 3. (A) Overall (OS) and (B) progression-free survival (PFS) after decitabine treatment. The median OS and PFS of all patients were 502 days and 201 days (95% CI, 50 to 351 days), respectively, from the starting date of the first decitabine treatment. CI, confidence interval.

Fig. 4. (A) Overall (OS) and (B) progression-free survival (PFS) after decitabine treatment according to the decitabine response (the responders and the non-responders). The OS rate was higher (p=0.174), and the PFS rate was significantly higher (p=0.003) in the responders than in the non-responders.

Fig. 5. Changes in (A) bone marrow (BM) blast, (B) white blood cell count, (C) hemoglobin, and (D) platelet count during the decitabine treatment. Decitabine treatment consistently reduced the fraction of BM blast, and the hemogram was also continuously improved.