Novel cytogenetic-based risk scores predict HCT outcomes for patients with CLL

Researchers have developed an advanced prognostic scoring system that incorporates cytogenetic-based risk stratification of patients with chronic lymphocytic leukemia (CLL). This new system can be used for counseling patients on treatment options including targeted therapy and hematopoietic cell transplant (HCT), comparing data across studies, and providing a benchmark for future treatment. 

The scoring system was developed through a retrospective analysis of outcomes of 606 patients with CLL who underwent reduced-intensity conditioning allogeneic HCT between 2008 and 2014 with results reported to the Center for International Blood and Marrow Transplant Research (CIBMTR).

Median age of patients was 58 years (range, 26–73). All patients had been previously treated for their disease; the median number of prior treatments was three (range, 1–10), with 13% in complete remission and 51% in partial remission.

Multivariate models incorporating disease status, comorbidity index, lymphocyte count, and white blood cell count at HCT were used to develop a prognostic scoring system. Cytogenetic assessments of karyotypic abnormalities and del(17p) were used to develop a cytogenetic-based risk classification system, stratifying patients into four risk groups.

Four-year outcomes by the low, intermediate, high, and very high-risk groups are shown in the table.

OutcomeLow riskIntermediate riskHigh riskVery high riskP-value
Overall Survival 70% 57% 54% 38% <0.0001
Progression-Free Survival 58% 42% 33% 25% <0.0001
Non-Relapse Mortality 19% 31% 25% 44% <0.0001
Relapse 23% 27% 41% 31% =0.007

Based on the results, researchers proposed an integrative approach of transplant and targeted therapy to improve the clinical outcomes in a high-risk population of patients with CLL. Patients would be induced into remission with targeted therapy, offered HCT during remission, and potentially reinstated with a targeted therapy for consolidation post-HCT.

Kim HT, et al., Clin Cancer Res