Role of Minimal Residual Disease in the Clinical Course of T cell Acute Lymphoblastic Leukemia in Pediatric Patients

Background Minimal Residual Disease (MRD) is the most important prognostic parameter in pediatric precursor B cell- Acute Lymphoblastic Leukemia (B-ALL). However, the feasibility of flow cytometry in the detection of Minimal Residual Disease (MRD) in T cell- Acute Lymphoblastic Leukemia (T-ALL) is not well defined. Objectives We aimed to investigate the prognostic impact of Flow Cytometry-MRD in T-ALL measured at different time points post-induction. Patients and methods In the current study, the impact of MRD was investigated in 58 newly diagnosed pediatric ALL at day 15, 28 and 42 post induction treatment in relation to other clinical and hematological parameters as well as disease-free survival. Results At day 15, day 28 and day 42 patients with MRD level ≥ 0.1% had inferior Disease-Free Survival (DFS) compared to patients with lower MRD levels which was significant for day 15, day 28 and 42 (p=0.007, p=0.0148 and p=0.0004 respectively). No association was detected between MRD status and different clinical and laboratory parameters. Conclusion Post-induction MRD detection is sensitively reflecting the disease progression in pediatric (T-ALL). This is most evident at day 42 followed by day 15.