We read with interest a recent paper by Tyagi, et al. [1] on cytogenetic profile of Indian children with acute myeloid leukemia (AML). The authors have described outcomes as per ENL classification [2]. They have reported event-free survival (EFS) of <35% in all risk groups [1]. Here we discuss few other Indian studies and our experience focusing on risk stratification and outcomes.

In a study of 51 children, cytogenetics could be done in 21 children (favorable10, intermediate 4, high-risk 7). EFS was 28.5% (favourable 20%, intermediate 50%, high-risk 20%) [3]. In another study of 65 children with AML, cytogenetics was available in 44 (favourable 18, intermediate 14, high risk 12). EFS was 28% (favourable risk 62%, intermediate risk 30% and high-risk 12.5%). Only two children with high-risk disease underwent matched sibling donor (MSD) hematopoietic stem cell transplant (HSCT) [4]. In another study of 247 patients (favourable 12%, intermediate 70% and high risk 18%), 109 opted for therapy of which 23 were children (4 underwent HSCT for non-favorable AML). Overall survival for children was 70% at median follow up of 7 months [5].

From 2015 to 2018, we diagnosed 24 children with AML, and cytogenetics and molecular genetics could be performed for 21 (favourable 13, intermediate risk 4, high risk 4). Children with acute promyelocytic leukemia (APML) were treated with arsenic and all-trans retinoic acid based therapy. All other children were treated with two courses of 3+7 induction therapy followed by four courses of high-dose cytarabine. Children with intermediate- and high-risk were offered allogeneic HSCT.

In favorable category, all five APML patients are alive and in complete remission (CR) 1; of eight children with t (8,21) translocation, five are alive in CR1 (one child with minimal residual disease underwent haploidentical HSCT). Three children relapsed one refused further therapy and remaining 2 underwent MSD HSCT, but both relapsed and died. Ten are alive in CR1 at median follow-up of 26 months. In intermediate risk category, out of four patients, three patients achieved CR1 and one patient died of refractory disease. One patient underwent haploidentical HSCT. One child relapsed and two are alive in CR1. In high-risk category, three patients achieved CR1 and one had refractory disease. One with FLT3-ITD refused HSCT, who relapsed later and died. Remaining three underwent haploidentical HSCT, of whom one with refractory disease relapsed and died. Two are alive in CR1. Overall, 67% children are alive in CR1 at median follow-up of 31 months (favourable 77%, intermediate 50%, high risk 50%). Five underwent HSCT in CR1 based on risk stratification of which four are alive and disease-free.

Our small series highlights that cytogenetic-based risk stratification can help improve outcomes by offering HSCT in non-favorable AML.

1. Tyagi A, Pramanik R, Chaudhary S, Chopra A, Bakhshi S. Cytogenetic Profiles of 472 Indian Children with Acute Myeloid Leukemia. Indian Pediatr. 2018;55:469-73.

2. Döhner H, Estey E, Grimwade D, Amadori S, Appelbaum FR, Büchner T, et al. Diagnosis and management of AML in adults: 2017 ELN recommendations from an international expert panel.　Blood. 2017;129:424-47.

3. Yadav SP, Ramzan M, Lall M, Sachdeva A. Pediatric acute myeloid leukemia: Final frontier for pediatric oncologists in developing world.　Pediatr Hematol Oncol.　2011;28:647-8.

4. Radhakrishnan V, Thampy C, Ganesan P, Rajendranath R, Ganesan TS, Rajalekshmy KR, et al. Acute myeloid leuk-emia in children: Experience from tertiary cancer centre in India.　Indian J Hematol Blood Transfus.　　2016;32:257-61.