Assessing the Impact of All-Trans Retinoic Acid (ATRA)- and Arsenic Trioxide (ATO)-Based Therapy in Pediatric Acute Promyelocytic Leukemia: A Single-Center Study.

BACKGROUND

Acute promyelocytic leukemia (APL) is a subtype of acute myeloid leukemia (AML) characterized by the t(15;17) translocation, leading to the PML-RARA fusion gene. While treatable, APL presents significant challenges, particularly in resource-constrained settings where delays in diagnosis and access to specialized care may impact outcomes. This study aims to describe the clinical presentation, treatment outcomes, and survival data for pediatric APL patients.

METHODS

This observational, retrospective, single-center study was conducted at Sher-i-Kashmir Institute of Medical Sciences (SKIMS), Srinagar, spanning for a period of six years. The study included 20 pediatric patients diagnosed with APL. Laboratory profiles, treatment regimens, and complications were analyzed. Risk stratification was done using modified Sanz criteria, and patients were treated according to the APL0406 and APML4 protocols. Overall survival (OS) and Progression-free survival (PFS) were calculated over a median follow-up period of three years.

RESULTS

Median OS was 88 months (95% CI= 79.612 to 97.188). The mean haemoglobin levels were 6.51 ± 1.82 mg/dL and patients had high PML-RARA transcript levels (5175.95 ± 3039.37). Common symptoms included mucocutaneous bleeding (19, 95%) and gum bleeding (10, 50%). Induction with all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) lasted a mean of 40.9 days. Febrile neutropenia (16, 80%) and differentiation syndrome (14, 70%) were frequent complications. One patient (1, 5%) died during induction.

CONCLUSION

This study reinforces the effectiveness of ATRA-ATO-based regimens in managing paediatric APL. However, induction-related complications such as febrile neutropenia, transaminitis, and QTc prolongation highlight the need for vigilant monitoring and robust supportive care. Timely diagnosis and early initiation of therapy remain key to improving outcomes.