Long term outcomes and risk factors for patients with advanced chronic myeloid leukemia who have undergone allogeneic stem cell transplantation

This study aimed to determine the long-term outcomes and risk factors after allogeneic stem cell transplantation (allo-SCT) for patients with advanced phase chronic myeloid leukemia (CML). 

This study concluded that allo-SCT improved the outcomes of these patients, particularly in those with donors younger than 36 years.  

Allogeneic hematopoietic stem-cell transplantation (allo-HSCT) remains the only curative option for patients with advanced chronic myeloid leukemia (CML). Allo-HSCT involves replacing the patients' cells with healthy cells from a donor after intensive chemotherapy to kill cancer cells. However, the outcomes of these patients have still remained poor and there have not been many long-term follow-up studies.  

The long-term outcomes and risk factors for patients with advanced CML treated with allo-HSCT are still unknown. 

This study involved 147 patients with advanced CML who had undergone an allo-HSCT between 1990 and 2018. 96 patients had a history of CML blast crisis and 51 patients had accelerated phase CML. The average follow-up was 9 years.

At 15 years, the overall survival (OS) rate was 34% and the progression-free survival (PFS) rate was 26%. A history of blast crisis before SCT did not affect survival. At 15 years, the occurrence of non-relapse mortality (NRM) was 28%. The occurrence of relapse was 43% at 15 years.  

Factors associated with a better prognosis of allo-SCT were having a donor aged 36 and younger and a higher CD34+ count in the graft. CD34+ is a protein found on blood cells that help restore bone marrow function. Another factor associated with a better prognosis was SCT from the peripheral blood.  

This study concluded that allo-SCT improved the outcomes of patients with advanced CML particularly in those with donors younger than 36 years and with higher CD34+ dose in the graft. 

This study was based on medical records. Information might have been missing. The outcomes were better for those transplanted later than 2008. The SCT technology has changed over time. This might have influenced the results.