Optimized outcome prediction of oncogenetic mutations in non-early T-cell precursor acute lymphoblastic leukemia

Early biomarkers allowing effective treatment stratification in adult T-cell acute lymphoblastic leukemia (T-ALL) patients remain elusive.

The mutation spectrum of 116T-ALL adult patients enrolled in the Shanghai Institute of Hematology (SIH)-based hospital network or Multicenter Hematology-Oncology Protocols Evaluation System (M-HOPES) in China were studied by using RNA-sequencing or targeted next generation sequencing. A comprehensive survival analysis based on clinical characteristics, immunophenotype and oncogenetic classifier was performed.

Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) has higher mutation rates of N/K-RAS and lower mutation rates of FBXW7 compared to non-ETP ALL, but the survival probability of ETP-ALL patients is similar to that of non-ETP ALL patients. T-ALLs with a NOTCH1/FBXW7 (N/F) mutation in the absence of RAS or PTEN abnormalities (NFRP class I) show a more favorable outcome compared to T-ALLs with no N/F mutation and/or with the presence of RAS/PTEN alterations (NFRP class II). A survival analysis of T-ALL, taking into account both the ETP-ALL/non-ETP T-ALL groups and the NFRP oncogenetic classifier, demonstrates that, within the non-ETP T-ALL subtype, NFRP class II identifies a group with poor prognosis and significant decreases of both OS (14.8% versus 50.9%, P = 0.019) and EFS (11.4% versus 42.4%, P = 0.001). In contrast, no survival difference is observed within ETP-ALL between the NFRP class I or class II (OS: 37.9% versus 33%, P = 0.876; EFS: 39.8% versus 33.7%, P = 0.969).

In summary, the oncogenetic classifier based on the NFRP classes is particularly useful to improve the stratification of non-ETP ALL.