Stem cell transplants can lead to excellent outcomes in certain B-cell lymphoma patients who failed to respond to chemoimmunotherapy, a study shows.
The results apply to patients with primary mediastinal B-cell lymphoma, or PMBCL.
Researchers published their study in the journal Bone Marrow Transplantation. The title is “Autologous stem cell transplantation for primary mediastinal B-cell lymphoma: long-term outcome and role of post-transplant radiotherapy. A report of the European Society for Blood and Marrow Transplantation.”
There are three phases in the treatment of PMBCL patients: induction, consolidation and maintenance.
In the induction phase, adding Rituxan (rituximab) to a standard chemotherapy regimen called CHOP has significantly improved patients’ outcomes. CHOP is a combination of cyclophosphamide, doxorubicine, vincristin, and prednisone.
Most patients receive radiotherapy during the consolidation phase of treatment. But doctors debate the benefit of this strategy, particularly in patients who respond fully to first-line chemo immuno radiotherapy, or CIT.
Some patients are unable to control their lymphoma after induction and consolidation treatment. This is particularly true if their cancer failed to respond to treatment or it returned early.
Many doctors have wondered if intensifying patients’ first-line CIT treatment, with or without a stem cell transplant, could benefit them.
A research team decided to see if a stem cell transplant could improve PMBCL patients’ outcomes.
They looked at 84 patients. At the time they received a transplant, 16 patients’ lymphoma was in remission after first-line chemotherapy, 44 patients’ cancer was in remission after salvage therapy for a primary or relapsed form of the disease, and 24 patients’ lymphoma was not responding to treatment. A salvage therapy is one that doctors try when a cancer fails to respond to standard treatment.
After three years, all patients who received the transplant after a first-line treatment had led to remission were still alive. Only 6% experienced a relapse. The disease of 94% failed to progress.
Adding radiation therapy during consolidation failed to produce any benefit.
Among patients who had responded to chemo but received a stem cell transplant after relapsing, 85% lived three years or more. The lymphoma of 64% percent failed to progress after the three years. Thirty-one percent experienced a relapse.
Only 41% of those whose cancer failed to respond to treatment were alive three years after a transplant. Fifty-two percent had relapsed. Only 39% had a disease that had failed to progress.
While patients in remission after salvage therapy did not benefit from radiation therapy, it may prevent the lymphoma from returning in those whose cancer failed to respond to treatment, researchers said.