(RxWiki News) Non-Hodgkin lymphoma is a term that covers various types of blood cancers that develop in the lymphatic system. Researchers recently set out to see if replacing these cancerous cells with healthy ones could help improve survival.
These researchers evaluated the survival benefits of early stem cell transplants to treat non-Hodgkin lymphoma (NHL) compared with standard chemotherapy.
While the overall group of NHL patients did not live longer after stem cell transplants, a small group of very high-risk patients did enjoy survival benefits, the study found.
"Discuss all of your treatment options with your oncologist."
Patrick Stiff, MD, director of Loyola University Medical Center’s Cardinal Bernardin Cancer Center, and colleagues conducted this study to see if early stem cell transplants — given before a relapse occurred — would increase survival in NHL patients who had undergone initial chemotherapy treatment.
First line treatment for non-Hodgkin lymphoma involves a chemotherapy cocktail of five medications: cyclophosphamide (brand name Cytoxan and others), doxorubicin HCl liposome (Doxil), vincristine (Oncovin and others), prednisone (Deltasone and others) and rituximab (Rituxan). This regimen is known as R-CHOP. Before the approval of rituximab in 2003, only four of the agents were used, and the regimen was called CHOP.
First line chemotherapy puts many patients into remission (significant reduction of disease), but eventually the disease may return (relapse).
For this study, 397 NHL patients were enrolled from 40 sites in the US and Canada between 1999 and 2007. All of the participants had received and responded to initial treatment with either the CHOP or R-CHOP regimens.
Of the 397 enrolled patients, 253 went on to be randomly assigned to treatment. About half (125) of the study members were randomly assigned to receive an autologous stem cell transplant, while the 128 patients assigned to undergo three additional cycles of R-CHOP served as the control group.
Patients were grouped according to their risk of the cancer returning — high risk or intermediate-high risk.
For an autologous stem cell transplant, the patient’s own stem cells are removed from either their blood or bone marrow before chemotherapy or radiation. Stem cells are like blank cells that can turn into any type of cell.
The transplant involves infusing the stem cells back into the patient. The transplanted stem cells go on to develop into healthy immune cells, replacing the immune cells that have been damaged or destroyed by treatment.
The researchers found after two years that 69 percent of the patients who had transplants were progression-free, meaning the disease had not relapsed, compared to 55 percent of the patients in the control group.
Of the transplant group, 74 percent were alive after two years, as were 71 percent of the patients in the control group. There were no significant statistical differences in the survival rates, according to the researchers.
The researchers believe that there was no major survival difference between the study members as a whole because control group patients were offered stem cell transplants at the time they relapsed.
Among the high-risk patients, though, there was a significant survival benefit, with 82 percent of patients in the transplant group still alive at two years, compared to 64 percent of high risk control group members.
Earlier studies have shown that non-Hodgkin lymphoma transplant patients may be at high risk of developing second cancers. This study found that both groups had roughly the same number of new cancers — 11 patients in the control group and 12 patients in the transplant group.
The researchers concluded that both early and late (after relapse) transplants had about the same impact on overall survival for patients in the combined risk groups. “Early transplantation appears to be beneficial for the small group of patients presenting with high-risk disease,” they wrote.
This study was published October 29 in The New England Journal of Medicine.
The National Cancer Institute funded the research.
A number of the authors disclosed financial relationships with various organizations and commercial entities, including pharmaceutical companies.