Comparison of Outcomes of Transplant and Nontransplant High-Risk Chronic Lymphocytic Leukemia Patients in the Novel Targeted Therapy Era.

OBJECTIVES

Our aim was to compare patients with high-risk chronic lymphocytic leukemia referred to our transplant center who underwent allogeneic stem cell transplant with those who did not receive this treatment. Factors compared included demographics, clinical characteristics, and survival rates in the novel targeted therapy era.

MATERIALS AND METHODS

All 33 patients with high-risk chronic lymphocytic leukemia who were referred to the hematopoietic stem cell transplant center were enrolled in this retrospective, single-center nonrandomized study. Outcomes of patients who received allogeneic stem cell transplant were compared with those of nontransplant patients. Chemoimmunotherapy and ibrutinib were given when indicated. Factors related to overall and progression-free survival were assessed.

RESULTS

Thirteen patients underwent allotransplant, and transplant was not done in 20 patients for various reasons. Demographic and clinical features of the transplant and nontransplant groups were similar. The estimated cumulative overall survival was 72.6 ± 15 and 84.3 ± 13 months in the nontransplant and transplant groups, respectively. The 5-year overall and progression-free survival rates in the transplant and nontransplant groups were 57.3%/36.0% and 40%/20.6%, respectively. In the nontransplant group, overall survival of those who used ibrutinib was longer than overall survival in patients in the transplant group who used the same drug, but the difference was not statistically significant. Although not significant, overall survival in patients who did not use ibrutinib was longer in the transplant group than in the nontransplant group. Cox regression analyses showed that transplant, relapse, and Binet stage were independent predictors of overall survival.

CONCLUSIONS

In patients who do not use ibrutinib, allogeneic stem cell transplant improved survival compared with nontransplant patients. Addition of ibrutinib provided comparable life expectancies, showing that allogeneic stem cell transplant and ibrutinib may have complementary roles. Transplant is still an independent predictor of overall survival.