Comorbidity evaluations can provide clinically useful prognostic information at the time of diagnosis of relapsed or refractory acute myeloid leukemia (AML), according to results of a phase II trial. These prognostic evaluations were based on the hematopoietic cell transplantation-specific comorbidity index (HCT-CI) and Eastern Cooperative Oncology Group (ECOG) score.
This multi-center trial included 84 patients, with a median age of 61 years (range, 40 to 75), who were scheduled for at least one cycle of salvage therapy with clofarabine and cytarabine. Chemoresponsive patients with a donor underwent HCT after their first salvage cycle.
After a median follow up of 40 months, the estimated 3-year overall survival (OS) for all study patients and those who underwent HCT within the trial was 40% and 55%, respectively.
In multivariate analysis, both the HCT-CI and ECOG score had a statistically significant impact on OS with a hazard ratio of 1.22 (p=0.025) and 1.72 (p=0.001), respectively. European LeukemiaNet (ELN) risk classification had a significant influence on OS (p=0.047), but it did not affect disease-free survival (p=0.20).
Two main conclusions from this study affect decision-making for physicians and their patients with relapsed/refractory AML. First, high-risk AML patients can experience good outcomes using a stringent strategy combining a clofarabine-based reinduction chemotherapy and early allogeneic HCT in aplasia. Second, the results show the clinical relevance of comorbidity evaluation at the time of diagnosis of relapsed/refractory AML. The evaluation can guide these high-risk patients and their physicians to decide between palliative therapy or an intensive, possibly curative approach such as HCT.
The researchers noted that the median age of 61 years of this patient cohort means this is a clinically meaningful group of patients and the results are realistic predictors of what can be achieved in similar patients with relapsed/refractory AML.