Prognostic Factors in Childhood Acute Myeloid Leukemia; Experience from A Developing Country

Background In the developed world, 5-years survival of childhood acute myeloid leukaemia (AML) has improved to 70%. However, the survival rates in the developing world are below 40%. The main contributing factors to these reduced survival rates are a late presentation, malnutrition and high treatment-related mortality. Aim To document the factors affecting treatment outcome of childhood AML at a tertiary care facility of Pakistan. Methods and Results All newly registered cases of AML under 18 years of age from January 1, 2012 onwards who completed their treatment before November 30, 2019 were included. Data of 219 cases of AML containing 140 (63.9%) males and 79 (36.1%) females was analyzed. The mean age was 6.30 +/- 3.66 years. Pallor was the commonest presenting features in 180 (82.2%) and M2 was the commonest French American-British (FAB) subtype in 103 (47.0%) cases. In univariate analysis, high white blood cells (WBC) count at presentation (P= .006), poor nutritional status (P= .005), unfavourable cytogenetics (P= .019), certain types of FAB AML subtype (P= .005), and use of etoposide in induction chemotherapy (P= .042) significantly adversely affected overall survival (OS). Neutropenic sepsis and bleeding were the major causes of treatment-related mortality. Response to induction chemotherapy was the most significant prognostic factor in the multivariate analysis (P= <.001). After a median follow-up of 40.96 +/- 26.23 months, 5-year OS and DFS of the cohort were 40.6% and 38.3% respectively. Conclusions In this largest cohort of childhood AML from Pakistan, high WBC count at presentation, malnutrition, unfavourable cytogenetics and use of etoposide during induction chemotherapy were associated with decreased OS and DFS rates. Response to the induction chemotherapy was the most significant prognostic factor.