Central nervous system involvement-positive disease in consolidation/maintenance stage is a poor prognostic factor in pediatric T-cell acute lymphoblastic leukemia: a Chinese single-center report.

BACKGROUND: The incidence of central nervous system (CNS) leukemia is approximately 5%-10% in pediatric T-cell acute lymphoblastic leukemia (T-ALL), typically conferring a poor prognosis. MATERIALS AND METHODS: We further investigated the relationship between prognosis and CNS status at different treatment stages, retrospectively examining 185 patients with pediatric T-ALL of 2131 consecutive patients with ALL seen between April 2008 and October 2020. RESULTS: Patients with CNS involvement-positive (CNSI+) disease during induction had lower initial platelet counts (P = .021), a higher proportion of ETP-ALL (P = .031), hepatomegaly (P = .034), and splenomegaly (P = .030), but a lower recurrence rate (P = .004) than those of patients with CNSI+ disease occurring in the consolidation/maintenance stages. Children with CNSI+ disease in the consolidation/maintenance stages by univariate/multivariate analyses had a significantly lower 10-year overall survival (OS) (46.2 ± 10.8%, 67.5 ± 9.5%, and 80.7 ± 3.4%, P = .003), event-free survival (EFS; 20.8 ± 8.3%, 48.0 ± 10.0%, and 77.4 ± 3.6%, P < .001), and a significantly higher cumulative recurrence rate (CRR) (76.8 ± 9.1%, 48.6 ± 10.1%, and 17.3 ± 3.3%, P < .001) than those of patients with CNSI+ disease in induction and those who were CNSI- (P values all <.05). PHF6, RELN, TP53, and IKZF1 mutations were more common in patients with CNSI+ observed during the consolidation/maintenance stages (P values all <.05), which may indicate a role in pathogenesis. CONCLUSION: CNSI+ disease, especially in the consolidation/maintenance stage, was an independent poor prognostic factor in pediatric T-ALL. HSCT partially improved outcomes of children with T-ALL. Individualized treatment strategies containing a combination of immunotherapy and targeted therapy in addition to chemotherapy may improve patient outcomes.