For many patients with non-Hodgkins lymphoma, the standard treatments can do more harm than good — a frustration that led scientists in the Clinical Research Division to search for a better way. Their findings, published in the Journal of Clinical Oncology, hold promise for future therapies.
While non-Hodgkins lymphoma can strike at any age, the disease finds a foothold in older people; the average patient age ranges from 60-65. And once it's in remission, it often returns. "Unfortunately, most people will relapse after their primary therapy, and most therapies in the past for patients with relapsed lymphoma have been targeted to younger adults," said lead author Dr. Ajay Gopal.
Physicians are reluctant to use the standard treatments of stem-cell or bone-marrow transplantation on older adults, believing it's too toxic. "That basically excludes half of the patients that have this diagnosis," Gopal said.
However, one treatment, first used in younger patients, looks promising. Working with radioactively tagged monoclonal antibodies, y-shaped proteins that can be created to bind to a certain specific substance — in this case, tumors — physicians are able to deliver very high doses of radiation to tumor sites, sparing the surrounding organs. Total-body irradiation or high-dose chemotherapy targets healthy cells as well as tumor cells, so researchers believe the targeted approach would be a safer and more effective treatment for older people.
The study recruited 24 patients who showed much higher risk features of their disease than average and treated them with the radioactively tagged monoclonal antibodies. After about two weeks, patients were given a transplant of their own stem cells, and the combination proved highly effective. "The most important finding was that it was tolerable. Even in a younger patient population, we would expect about a five percent chance of a life-threatening complication. But out of 24 patients, albeit the number is relatively small, we didn't have any fatal complications," Gopal said. "We're optimistic that this approach, if not better, at least matches the data we see in younger patients with a much more toxic approach that we wouldn't even offer to older adults."
The team plans to continue studying treatments and is looking at drugs that have greater synergy with radiolabeled antibodies. Gopal received funding for the study from the National Cancer Institute, the Lymphoma Research Foundation and private gifts.