Recurrent genetic abnormalities detected by FISH in adult B ALL and association with hematological parameters

An easy-to-use nomogram predicting overall survival of adult acute lymphoblastic leukemia

Adult acute lymphoblastic leukemia (ALL) is heterogeneous both biologically and clinically. The outcomes of ALL have been improved with the application of children-like regimens and novel agents including immune therapy in young adults. The refractory to therapy and relapse of ALL have occurred in most adult cases. Factors affecting the prognosis of ALL include age and white blood cell (WBC) count at diagnosis. The clinical implications of genetic biomarkers, including chromosome translocation and gene mutation, have been explored in ALL. The interactions of these factors on the prediction of prognosis have not been evaluated in adult ALL. A prognostic model based on clinical and genetic abnormalities is necessary for clinical practice in the management of adult ALL. The newly diagnosed adult ALL patients were divided into the training and the validation cohort at 7:3 ratio. Factors associated with overall survival (OS) were assessed by univariate/multivariate Cox regression analyses and a signature score was assigned to each independent factor. A nomogram based on the signature score was developed and validated. The receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to assess the performance of the nomogram model. This study included a total of 229 newly diagnosed ALL patients. Five independent variables including age, WBC, bone marrow (BM) blasts, MLL rearrangement, and ICT gene mutations (carried any positive mutation of IKZF1, CREBBP and TP53) were identified as independent adverse factors for OS evaluated by the univariate, Kaplan-Meier survival and multivariate Cox regression analyses. A prognostic nomogram was built based on these factors. The areas under the ROC curve and calibration curve showed good accuracy between the predicted and observed values. The DCA curve showed that the performance of our model was superior to current risk factors. A nomogram was developed and validated based on the clinical and laboratory factors in newly diagnosed ALL patients. This model is effective to predict the overall survival of adult ALL. It is a simple and easy-to-use model that could efficiently predict the prognosis of adult ALL and is useful for decision making of treatment.

Recurrent genetic abnormalities detected by FISH in adult B ALL and association with hematological parameters

Background

Recurrent genetic abnormalities influence prognosis in B lymphoblastic leukemia. BCR‐ABL rearrangement is associated with higher leukocyte counts and older age at presentation. Among adults, BCR ‐ABL ‐ is the commonest recurrent abnormality whereas, IgH rearrangements are rare.

Aim

Aim of this study was to identify common recurrent genetic abnormalities in adult B ALL and study their association with hematological findings.

Methods

Bone marrow and peripheral blood from patients with B acute lymphoblastic leukemia were analyzed for complete blood counts, bone marrow morphology and cytogenetic abnormalities. The study group was divided into smaller groups based on cytogenetic abnormalities. Hematological parameters and presence of recurrent genetic abnormalities was compared across age groups and gender by non parametric tests.

Results

BCR‐ABL positive group had a higher leukocyte count than BCR‐ABL negative group. Among groups 1 to 5, group 1 with gains of chromosomes was associated with leucopenia and higher age at presentation. BCR‐ABL is commonest recurrent abnormality followed by IgH rearrangements.

Conclusion

Patients with gains of chromosomes alone have low total leukocyte counts at presentation.