Evaluating the long-term outcomes of Zevalin for patients with advanced B cell lymphoma

This study evaluated the long-term outcomes of patients with advanced (stage 3 – 4) non-Hodgkin’s lymphoma (NHL) who received radioimmunotherapy before allogeneic stem cell transplantation (alloSCT). This study concluded that this treatment regimen improved survival in most of these patients.

AlloSCT involves replacing the patient’s stem cells with healthy stem cells from a donor. High-dose chemotherapy is typically used before SCT to get rid of any remaining cancer cells. This type of chemotherapy is called a conditioning regimen. However, many patients with aggressive or chemoresistant (does not respond to chemotherapy) disease experience relapse.

Radioimmunotherapy with ibritumomab tiuxetan (Zevalin) may help these patients achieve better outcomes after alloSCT. This type of treatment uses monoclonal antibodies that release radiation directly on the tumor. The long-term outcomes after this treatment in patients with advanced NHL remain under investigation.

This study involved 40 patients with advanced NHL. 14 (35%) patients had diffuse large B-cell lymphoma (DLBCL). 8 patients had mantle cell lymphoma (20%) and 6 had follicular lymphoma (15%). Patients were followed up for an average of 9 years.

Overall, 60% of patients responded to treatment. 35% of patients had the disappearance of all signs of cancer (complete response). 83% of the patients with FL, 50% with MCL, and 38% with DLBCL responded to treatment.

For all patients, the 5-year overall survival (OS; patients still alive 5 years later) was 40%. 5-year progression-free survival (PFS; patients still alive 5 years later without tumor growth or spread) was 27.5%. For patients with indolent (painless) disease, these rates were 44% (PFS) and 67% (OS).

At follow-up, 6 (15%) patients experienced life-threatening infections. 11 (27.5%) patients reported long-lasting graft-versus-host disease (the donated stem cells attack the patient’s healthy cells).

This study concluded that radioimmunotherapy followed by alloSCT improved survival outcomes in most patients with advanced NHL. 

The patient population in this study was quite small. Larger studies are needed to confirm these results.