Risk-based outcome of childhood AML: Experience of National Guard Hospital, Jeddah, Saudi Arabia.

Abstract

9575 Background: Risk stratification based on cytogenetics and percentage of bone marrow (BM) blasts after one course of chemotherapy influences outcome of childhood AML with event-free survival (EFS) and overall survival (OS) of 61% and 71%, 39% and 51%, and 35% and 35%; with chemotherapy for low-risk (LR), intermediate-risk (IR), and high-risk (HR), respectively, and EFS and OS of 50% and 61% for patients with unknown cytogenetics respectively (Horan JT et al. JCO 2008:26:5797-5801). Objectives:We analyzed the complete remission rate after one course of chemotherapy (CR), EFS, and OS in our center based on risk stratification. Methods: Patient files with childhood AML from 1985 to 2009 were reviewed for age, sex, CNS disease, BM cytogenetics, and CR rate to analyze EFS, and OS based on CR and cytogentic-risk. Results: There were 74 consecutive patients diagnosed with AML. AML-M3 were excluded (n = 5) and complete data for risk stratification were available in 50 patients. Mean age 6 years (range 0.7 – 14), Male: Female ratio 3.4:4, positive CSF 7/74 (10%), and BM cytogenetics were LR (n = 12); t (8;21) (n = 6) and inversion 16 (n = 6), IR (n = 15); normal cytogenetics (n = 3) and other translocation (n = 12), and HR (n = 3); monosomy 7, abn(3q), and complex cytogenetics (one each). Cytogenetics were unknown in 20 patients; failed (n = 4) and not done (n = 16). CR was achieved in 48/50 (96%) patients after course 1. Therefore, final risk stratification was as follows: LR (n = 12), IR (n = 14), unknown (n = 20), and HR (n = 4). Median follow-up duration 5 years. Table summarizes results. Conclusions: International risk- based stratification influenced outcome in our population. Patients with unknown cytogenetics had inferior outcome despite achieving CR post course 1. This highlights the importance of cytogenetic stratification. Targeted therapy and early stem cell transplant in high-risk patients may improve outcome further. Risk N = 50 CR post-course 1 EFS (%) OS (%) Low risk 12 (24%) 12/12 (100%) 8/12 (67%) 10/12 (83%) Intermediate risk 14 (28%) 14/14 (100%) 8/14 (57%) 9/14 (64%) Unknown cytogenetics 20 (40%) 20/20 (100%) 7/20 (35%) 7/20 (35%) High risk 4 (8%) 2/4 (50%) 1/4 (25%) 1/4 (25%) No significant financial relationships to disclose.