General AML

A comparison of the outcomes in adolescents/young adults and pediatric AML and APL patients

Adolescents and Young Adults (AYAs) are a significant group of patients who are often treated with pediatric and adult treatment protocols1. AYAs are defined as patients aged between 15 to 30 years and there is a paucity of studies on the outcomes and characteristics of AYAs with either Acute Myeloid Leukemia (AML) or Acute Promyelocytic Leukemia (APL).

In an article in Clinical Lymphoma, Myeloma and Leukemia, published in February 2017, Syed S. Nasir from The University of  Tennessee Health Science Center, Memphis, USA, and colleagues reported their data in which they compared the outcomes of AYA patients versus pediatric patients (aged between 0 to 18 years)  diagnosed with either AML or APL.2

Using the large, population based Surveillance Epidemiology and End Results (SEER)-18 registry, the authors identified 6,343 AML patients; 45% (n = 2,836) were AYA AML patients (median age = 25 years). Also identified for this study were 920 APL patients; 59% were AYAs (median age = 21 years).

The key results of the study were:
  • Early Mortality Rate (EMR) in pediatric and AYA AML patients; 6.2% vs 9.2%, P < 0.01
  • 5-year Overall Survival (OS) in pediatric and AYA AML patients; 48.2% vs 36.4%, P < 0.01
  • EMR in pediatric and AYA APL patients; 11.4% vs 14.1%, P = 0.23
  • 5-year OS in pediatric and AYA APL patients; 68.2% vs 73.1%, P = 0.11
  • EMRs in pediatric and AYA AML patients (6.2% and 9.2%, respectively) vs EMRs in pediatric and AYA APL patients (11.4% and 14.1%, respectively); P ≤ 0.01
  • OS in pediatric and AYA AML patients (48.2% and 36.4%, respectively) vs OS in pediatric and AYA APL patients (68.2% and 73.1%, respectively); P ≤ 0.01

In summation, this is the first study to compare the survival outcomes of AYA and pediatric patients with APL and same age counterpart patients with AML. However, the authors highlighted that lack of cytogenetic and treatment data, which were not reported in the SEER database, was a limitation of their study.

AYA patients have a worse prognosis compared with pediatric patients with AML. However, AYA APL patients have similar outcomes with pediatric APL patients. The authors concluded by suggesting that more studies are required to further question how the treatment of AYAs with adult versus pediatric treatment regimens affect their outcomes. Furthermore, future clinical studies should be focused on AYAs so as to establish appropriate treatment for this group of patients.

Abstract
Background

Studies on the outcome of adolescents and young adults (AYAs) with acute myeloid leukemia (AML) and acute promyelocytic leukemia (APL) are limited.

Methods

We compared the outcome of AYA (19-30 years) patients with AML and PML and pediatric (0-18 years) patients with AML (pAMLs) and APL (pAPLs) utilizing the Surveillance Epidemiology and End Results-18 registry. Early mortality rate (EMR), defined as mortality within 1 month of diagnosis, was used as a surrogate for treatment-related mortality. Survival statistics were computed using the Kaplan-Meier method. Multivariate analysis was done using logistic regression and the Cox proportional hazard regression model.

Results

A total of 6343 patients with AML were identified; 44.7% were AYAs. pAMLs had lower EMR (6.2% vs. 9.2%; P < .01) and higher overall survival (OS) (1-year, 70.3% vs. 62.1%; 5-year, 48.2% vs. 36.4%; P < .01). Nine hundred twenty patients with APL were also identified; 59.5% were AYAs. No statistically significant difference was found between AYAs with APL and pAPLs in EMR (11.4% vs. 14.1%; P = .23) and OS (1-year, 83.8% vs. 81.2%; P = .31 and 5-year, 68.2% vs. 73.1%; P = .11]. Comparing all patients with AML and APL, AYAs with APL and pAPLs had higher EMR (11.4% and 14.1% vs. 6.2% and 9.2%; P ≤ .01) but better OS than AYAs with AML and pAMLs (5-year OS, 68.2% and 73.1% vs. 48.2% and 36.4%; P ≤ .01).

Conclusion

Our analysis shows AYAs with AML have worse EMR and OS compared with pAMLs. AYAs with APL and pAPLs have similar outcomes. To our knowledge, this is the first study reporting outcomes of AYAs with APL and pAPLs using a large population-based registry and their comparison with same age patients with AML.

References
  1. Canner J. et al. Differences in outcomes of newly diagnosed acute myeloid leukemia for adolescent/young adult and younger patients: a report from the Children's Oncology Group. Cancer. 2013 Dec 1; 119(23):4162–4169. DOI: 1002/cncr.282342. Epub 2013 Sep 19.
  2. Nasir S.S. et al. Outcome of Adolescents and Young Adults Compared With Pediatric Patients With Acute Myeloid and Promyelocytic Leukemia. Clinical Lymphoma, Myeloid & Leukemia. 2017 Feb; 17(2):126–132.e1. DOI: 1016/j.clml.2016.09.011. Epub 2016 Sep 17.