ASH 2017 | Two versus three cycles of consolidation chemotherapy in patients with CBF-AML

Daniel Sawler from the University of Alberta, Edmonton, AB, Canada, on behalf of colleagues presented at the 59th American Society of Hematology (ASH) Annual Meeting, Atlanta, GA, on Sunday 10^th December 2017, results from a retrospective study, which evaluated the clinical impact of two cycles of consolidative chemotherapy on the outcomes of patients with Core Binding Factor (CBF)-Acute Myeloid Leukemia (AML).

The speaker began his talk by highlighting that the optimal number of consolidation therapy cycles required for optimal outcomes in patients with CBF-AML is not yet elucidated. Additionally, there is a paucity of studies that have directly compared two cycles of consolidative therapy to three cycles in patients with CBF-AML.

The speaker then discussed the design of their retrospective study. Briefly, 108 newly diagnosed CBF-AML patients) who were treated at two Canadian centers with either two cycles (n = 34, median age = 43 years) or three cycles (n = 74, median age = 49 years) of consolidative therapy after Complete Remission (CR) between 2003–2015 were retrospectively analyzed in this study.

Key findings:

• Median follow-up in patients who received two and three cycles of consolidation; 85 vs 30 months, P < 0.0001
• Death (n = 9) occurred in patients that received two cycles of consolidation during induction (n = 2), consolidation (n = 1), after relapse (n = 4) and in CR (n = 2)
• Death (n = 18) occurred in patients that received three cycles of consolidation during induction (n = 3), consolidation (n = 1), after relapse (n = 12) and in CR (n = 2)
• 5-year OS in patients who received two and three cycles of consolidation were 73% and 71% respectively, P = 0.96
• 5-year Relapse Free Survival (RFS) in patients who received two and three cycles of consolidation were 63% and 57% respectively, P = 0.61

The speaker highlighted that the study has some key limitations including its retrospective nature. Additionally, c-kit mutational analysis was absent prior to 2008 and there was a lack of minimal residual disease data.

In summary, compared to three cycles, two cycles of consolidation therapy did not reduce OS or RFS in CBF-AML patients. The speaker suggested that a reduction in chemotherapy may provide both economic and quality of life benefits for patients. He further concluded by noting that the findings of this retrospective study should be confirmed in a large prospective study. Additionally, assimilation of additional data comparing two cycles versus four cycles of consolidation should be carried out.