Acute Leukemia of Ambiguous Lineage in Elderly Patients - Analysis of Survival Using Surveillance Epidemiology and End Results-Medicare Database

Background: Acute leukemia of ambiguous lineage (ALAL) is a rare leukemia with sparse data availability about the survival and management strategies in elderly patients.

Methods: We used the Surveillance Epidemiology and End Results (SEER)-Medicare database to describe the overall survival (OS) and treatment pattern of elderly patients (age > 65 years) with ALAL. OS analysis was done using the Kaplan-Meier method, and its determinants were analyzed using the Cox proportional hazard regression method with a significant P < .05.

Results: We included 705 patients with ALAL and a median age of 80 years. The 2-year OS was 16.4% for patients aged 66 to 70 years, 8.1% for patients aged 71 to 75 years, 5.5% for patients aged 76 to 80 years, and 3.7% for patients aged > 80 years (P < .01). Two-year OS did not significantly vary by race or gender. Among the study cohort, 151 patients received chemotherapy. Two-year OS was 17% in the chemotherapy group and 3% in the no-chemotherapy group (P < .001). On multivariate analysis, age less than 80 years (Age 66-70 years: hazard ratio [HR]; 0.66, 95% confidence interval [CI], 0.52-0.85; age 71-75 years: HR, 0.80; 95% CI, 0.65-0.99; age 76-80 years: HR, 0.80; 95% CI, 0.66-0.98; P = .004) and chemotherapy (HR, 0.51; 95% CI, 0.42-0.62; P = .001) significantly reduced the hazard for mortality.

Conclusion: Our study suggests that the OS of elderly patients with ALAL remains poor. Although treatment improved the OS, only 21.5% of patients received therapy. The optimal choice of therapy needs to be determined by prospective studies.