Outcomes and prognostic factors of adults with refractory or relapsed T-cell acute lymphoblastic leukemia included in measurable residual disease-oriented trials.

Despite high complete remission (CR) rates with frontline therapy, relapses are frequent in adults with T-cell acute lymphoblastic leukemia (T-ALL) with limited salvage options. We analyzed the outcomes and prognostic factors for CR to salvage therapy and overall survival (OS) of patients with R/R T-ALL included in two prospective measurable residual disease-oriented trials. Seventy-five patients (70 relapsed, 5 refractory) were identified. Relapses occurred in bone marrow, isolated or combined in 50 patients, and in the central nervous system (CNS; isolated or combined) in 20. Second CR was attained in 30/75 patients (40%). Treatment with FLAG-Ida and isolated CNS relapse were independently associated with a higher CR rate after first salvage therapy. The median OS was 6.2 (95% confidence interval [CI], 3.9-8.6) months, with a 4-year OS probability of 18% (95% CI, 9%-27%). No differences in survival were observed according to the treatment with hematopoietic stem cell transplantation in patients in CR after first salvage therapy. Multivariable analysis showed a ≥12-month interval between first CR and relapse, CR after first salvage therapy and isolated CNS relapse as favorable prognostic factors for OS with hazard ratios (HR) (95% CI) of 1.931 (1.109-3.362), 2.958 (1.640-5.334), and 2.976 (1.157-7.655), respectively. This study confirms the poor outcomes of adults with R/R T-ALL among whom FLAG-Ida was the best of the rescue therapies evaluated. Late relapse, CR after first rescue therapy and isolated CNS relapse showed prognostic impact on survival. More effective rescue therapies are needed in adults with R/R T-ALL.

Bone marrow VEGFC expression is associated with multilineage dysplasia and several prognostic markers in adult acute myeloid leukemia, but not with survival.

Vascular endothelial growth factor C (VEGFC) stimulates leukemia cell proliferation and survival, and promotes angiogenesis. We studied VEGFC expression in bone marrow samples from 353 adult acute myeloid leukemia (AML) patients and its relationship with several clinical, cytogenetic, and molecular variables. We also studied the expression of 84 genes involved in VEGF signaling in 24 patients. We found that VEGFC expression was higher in AML patients with myelodysplasia-related changes (AML-MRC) than in patients with non-AML-MRC. We also found an association between VEGFC expression and the patient cytogenetic risk group, with those with a worse prognosis having higher VEGFC expression levels. No correlation was observed between VEGFC expression and survival or complete remission. VEGFC expression strongly correlated with expression of the VEGF receptors FLT1, KDR, and NRP1. Thus, in this series, VEGFC expression was increased in AML-MRC and in subgroups with a poorer prognosis, but has no impact on survival.