Evaluating outcomes after haploSCT for patients with classical Hodgkin lymphoma

This study evaluated the outcomes of patients with classical Hodgkin lymphoma (cHL) after reduced-intensity chemotherapy and haploidentical stem cell transplantation (haploSCT). This study concluded that this treatment approach is as effective as allogeneic SCT (alloSCT), but with fewer long-term complications.

AlloSCT is an effective therapy for patients with HL who relapse after autologous SCT (involves healthy stem cells from the patient). AlloSCT involves replacing the patient’s cancer cells with healthy stem cells from a donor. This requires a close tissue type match between the donor and the patient so that the donor’s cells do not attack the patient’s healthy cells. This attack is called GVHD (graft-versus-host disease).

70% of patients do not have an exact tissue type match. For these patients, a haploidentical transplant (haploSCT; uses stem cells from a half-matched donor) can achieve a 50% match. Before the transplant, chemotherapy is given first to get rid of any remaining cancer cells. Reduced-intensity chemotherapy (RIC) has been associated with fewer side effects and improved survival. The outcomes of patients with cHL after haploSCT combined with RIC are unclear.

This study had 596 patients with cHL. All patients received RIC first. Then, 139 patients received haploSCT and 457 patients had a matched donor for conventional allo-SCT. Patients were followed-up for an average of 37 to 52 months.

After chemotherapy, 223 patients had a complete disappearance of all signs of cancer. Another 260 patients had tumor shrinkage (partial response).

Overall, 63% of patients in both groups were still alive 3 years later. Slightly more patients in the haploSCT group were still alive without tumor growth or spread compared to the alloSCT group (38% vs. 34%).

At 180 days after treatment, significantly more patients in the haploSCT group developed GVHD compared to patients in the alloSCT group (45% vs. 30%). However, significantly more patients in the alloSCT group had long-lasting GVHD 1 year later compared to the haploSCT group (46% vs. 23%). HaploSCT was significantly associated with a 55% lower risk of developing long-lasting GVHD.

1 year later, significantly more patients in the alloSCT group had the cancer return (42% vs. 32%). HaploSCT was significantly associated with a 26% lower risk of the cancer returning.

This study concluded that haploSCT with reduced-intensity chemotherapy is as effective as alloSCT, but with fewer long-term complications.

This study collected data from a registry. This may limit the conclusions that may be drawn. More studies are needed to confirm these results.