Autologous Stem Cell Transplants Improve Survival in Transformed Follicular Lymphoma

Treatment with an autologous stem cell transplant resulted in improved overall survival compared to treatment with an allogeneic stem cell transplant or a Rituxan (rituximab)-based chemotherapy regimen in patients with transformed follicular lymphoma. These results were recently published in the Journal of Clinical Oncology.

Follicular lymphoma is a type of non-Hodgkin’s lymphoma, in which cancer originates in the immune system. Follicular lymphoma is typically a slow-growing type of cancer; however, it can transform into a more aggressive type of lymphoma in some patients.

Treatment for follicular lymphoma that has become aggressive (transformed) often involves more aggressive therapy than used to treat the slower-growing form. Aggressive therapies may consist of a stem cell transplant or treatment consisting of the targeted agent Rituxan plus chemotherapy.

A stem cell transplant is a type of procedure in which high doses of chemotherapy and/or radiation are used for aggressive types of cancers. These high doses also kill healthy cells, including important blood cells. In order to replace these blood cells, stem cells are collected from circulating blood and re-infused into the patient. The stem cells mature into the type of blood cells needed.

An autologous stem cell transplant (auto SCT) uses the patient’s own stem cells, which are collected prior to the high –dose therapy and later infused back into the patient following the high doses of therapy.

An allogeneic stem cell transplant (allo SCT) uses stem cells collected from a matched donor. Unfortunately, when donor stem cells are infused into the patient following high-dose therapy, they may attack healthy cells in the patient’s body and cause severe side effects. However, they may also mount an attack against the cancer cells that still remain, providing additional benefits of therapy.

Researchers from Canada recently conducted a clinical trial to compare different treatment approaches for patients with transformed follicular lymphoma. This trial included 172 patients who were treated with either an auto SCT, an allo SCT, or a Rituxan/chemotherapy combination without a SCT.

5 years after transformation of the disease, overall survival was 65% for patients treated with an auto SCT, 61% for those treated with Rituxan/chemotherapy, and 46% for those treated with an allo SCT.
Mortality directly related to therapy was 23% for allo SCT and 5% for auto SCT
Individual variables of patients affected treatment outcomes.
The researchers concluded that “Patients undergoing autoSCT had better outcomes than those treated with rituximab-containing chemotherapy alone. AlloSCT did not improve outcome compared with rituximab-containing chemotherapy and was associated with clinically significant toxicity.” However, treatment options for transformed follicular lymphoma should take into consideration a multitude of variables so that therapy is personalized for each patient.

Reference: Villa D, Crump M, Panzarella T, et al. Autologous and Allogeneic Stem-Cell Transplantation for Transformed Follicular Lymphoma: A Report of the Canadian Blood and Marrow Transplant Group. Journal of Clinical Oncology. 2013; 13(9): 1164-1171.