Early T-cell precursor acute lymphoblastic leukemia and other subtypes: a retrospective case report from a single pediatric center in China.

PURPOSE Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) is rare in China and case reports are varied. We conducted an in-depth analysis of newly diagnosed children with T-ALL from January 1999 to April 2015 in our center, to show the biological differences between Chinese ETP-ALL children and other immune types of T-ALL. METHODS The newly diagnosed children with T-ALL were divided into four groups according to their immunophenotype: ETP-ALL, early non-ETP-ALL, cortical T-ALL and medullary T-ALL. Disease-free survival (DFS), event-free survival (EFS), and overall survival (OS) rates were estimated by the Kaplan-Meier method. The Cox regression model was used for multivariate analysis. RESULTS A total of 117 newly diagnosed children with T-ALL were enrolled in this study. The 10-year EFS and OS rates for all patients were 59.0 ± 4.7% and 61.0 ± 4.7%, respectively, with a median follow-up of 64 (5-167) months. Univariate analysis showed that ETP-ALL patients had the lowest 10-year DFS rate of 32.1 ± 11.7%, while cortical T-ALL had the highest DFS rate of 81.3 ± 8.5% compared with early non-ETP-ALL (61.6 ± 7.0%) and medullary T-ALL (59.1 ± 10.6%). Multivariate analysis demonstrated that only ETP-ALL and involvement of the central nervous system were independent prognostic factors. CONCLUSION Compared with other subtypes, pediatric ETP-ALL had a poor treatment response and high recurrence rate while cortical T-ALL appeared to have much better outcome. Our observations highlight the need for an individualized treatment regime for ETP-ALL.