Real-World Outcomes in Acute Promyelocytic Leukemia: A 13-Year Cohort from Qatar

Background: Acute promyelocytic leukemia (APL) is among the most curable acute leukemias, but real-world early mortality continues to undermine population-level cure. This study evaluated long term outcomes and prognostic factors among adults with APL treated in a single tertiary center in Qatar. Methods: We conducted a retrospective cohort study of consecutive adults diagnosed with APL between 2012 and 2024. Demographic, clinical, and laboratory data at baseline, treatment protocols, and response were extracted from electronic records. Overall survival (OS) was estimated using the Kaplan–Meier method, and prognostic variables were assessed with log-rank tests and Cox regression. This retrospective cohort included 87 adults. Patients were stratified by Sanz risk criteria: low risk (WBC ≤10×10⁹/L and platelets >40×10⁹/L), intermediate risk (WBC ≤10×10⁹/L and platelets ≤40×10⁹/L), and high risk (WBC >10×10⁹/L). Results: Of 87 patients (median age 36 years; 47.1% Sanz high-risk), 26.4% (n=23) died within 30 days of diagnosis, principally from intracranial hemorrhage (47.8% of early deaths). Among 71 treated patients, the complete remission (CR) rate was 84.1%; the highest CR rate was observed with ATRA–ATO (Lo-Coco, 90.9%). Treatment-related complications occurred in 73.2%; infection (66.2%) and differentiation syndrome (21.1%) were most frequent. Three-year overall survival (OS) was 93% (low-risk), 88% (intermediate-risk), and 56% (high-risk; log-rank p=0.001). ICU admission and non-receipt of treatment were independent predictors of death (multivariable HR 5.42 and 8.06, respectively). Excluding patients presenting with ICH, early mortality was 14.7%, and 5-year OS reached 87.6%. Conclusion: The study highlights the effectiveness of contemporary APL treatments but also underscores persistent early mortality due to hemorrhagic complications. Timely diagnosis and rapid initiation of therapy are crucial for improving patients' outcomes. Embedding APL-recognition bundles in emergency pathways, ensuring immediate empiric ATRA availability, and prompt coagulopathy correction are the most actionable priorities for reducing mortality.