The impact of graft-versus-lymphoma effect on outcomes after reduced intensity conditioned stem cell transplant

This study aimed to investigate the impact of the graft-versus-lymphoma effect on the outcomes for patients with leukemia/lymphoma who are treated with reduced-intensity conditioning (RIC) with alemtuzumab (Lemtrada) allogeneic hematopoietic stem cell transplant (allo-HSCT). 

This study concluded that the graft-versus-lymphoma effect leads to good long-term outcomes and is a protective factor against relapse for these patients.

Allogeneic hematopoietic stem cell transplant (allo-HSCT) is a potentially curative therapy for patients with relapsed/unresponsive leukemia/lymphoma. Allo-HSCT is a procedure where the patient receives blood-forming stem cells from a non-identical donor such as a sister or brother. 

Reduced-intensity conditioning (RIC) uses less chemotherapy to kill cancer cells before a transplant. RIC with alemtuzumab reduces transplant-related mortality and graft-versus-host disease (GvHD). RIC may also be associated with an increased risk of relapse. GvHD can occur after an allo-HSCT. It occurs when the stem cells view the body as foreign and begin to attack it. Graft versus lymphoma (GVL) effect is a good response that occurs when donor cells attack lymphoma cells. Alemtuzumab is a monoclonal antibody. It works by targeting cancer cells to destroy them. 

The impact of the GVL effect on outcomes for patients with leukemia/lymphoma treated with RIC-alemtuzumab-alloHSCT is still unknown.

This study involved 288 patients with leukemia/lymphoma. 57% of patients had non-Hodgkin’s lymphoma, 24% had Hodgkin’s lymphoma, and 19% had chronic lymphocytic leukemia (CLL). 58% of all patients involved had relapsed/unresponsive disease. All patients underwent RIC-alemtuzumab-alloHSCT. Patients were followed for an average of 64 months.

The five-year overall survival rate was 47%. The relapse rate after 5 years was 33%. The GvHD/relapse-free survival rate was 37%. 

GVHD occurred in 22% of patients at 100 days. This rate was 21% at 5 years. The presence of GvHD protected against relapse. Patients who received stem cells from an unrelated donor were also protected from relapse.

This study concluded that the GVL effect leads to good long-term outcomes and is a protective factor against relapse for patients with leukemia/lymphoma who are treated with RIC-alemtuzumab-alloHSCT.

This study was based on medical records. Some data might have been missing.