الفهرس 
cover EnglishOnly 14 pages are availabe for public view
 |  | from | 234 |  |  |
| | | from | 234 | | |
Abstract
Abstract Background: Minimal residual disease (MRD) in childhood acute lymphoblastic leukemia (ALL) during the early stages of therapy is statistically significant indicator of outcome.Aim: To study the prognostic significance of MRD by flow-cytometry in peripheral blood (PB) on day-8 induction in pediatric B-precursor ALL. Patients and Methods: This is study included 140 newly diagnosed B-precursor ALL pediatric patients treated at the Children’s Cancer Hospital- Egypt during the period between mid of March 2010 and end of September 2011. ALL patients received adopted protocol of St. Jude Children’s Research Hospital total study XV for low or standard/high risk ALL. Results: The 3-year relapse-free survival (RFS) and event-free survival (EFS) were 87±3.5% and 82±3.7% respectively. Median follow up was 34.9 months (range 24–42). MRD PB day-8 <1% was encountered in 78% of patients. Patients with day-8 MRD <1% had 3-year RFS of 90.6±3.4% compared to 73±10.7% for day-8 MRD ≥1% (P=0.042). Prognostic factors had statistically significant impact on RFS by univariate analysis were patient risk, favorable triple trisomies, and MRD PB day-8. By multivariate analysis, patient risk was the only independent factor affecting RFS. (HR= 6.9; and 95% (CI):1.7-27.8). Day-8 PB MRD had statistical significant association with initial TLC, DNA index, molecular cytogenetic including t(12,21), t(1,19), t(9,22), risk groups, MRD day-15, and MRD day-42. Patients having favorable double or triple trisomies with MRD PB day-8 <1% had 3-years RFS of 97±2.7% compared with 74±16% for similar patients having MRD day-8 ≥ 1% (P=0.028).Conclusions: Flow-cytometry MRD PB day-8 induction constitutes an early prognostic index for children with B-Precursor ALL. MRD PB day- 8 can help in identification of a subgroup of patients with favorable double or triple trisomies in whom de-escalation of therapy can be considered especially in developing countries to help reducing therapy.