It’s tough enough hearing a diagnosis of cancer without also finding out that you’re too old for a treatment that might save your life.
Non-Hodgkin’s lymphoma patients ages 60 and older have traditionally been excluded from hematopoietic stem cell transplants — commonly known as bone marrow transplants — because of the side effects. Yet these patients often have aggressive lymphomas that respond to such treatment.
Now Amrita Krishnan, M.D., and her City of Hope colleagues have devised a new transplant procedure that appears to work well among older patients.
“The issue was that older patients with lymphoma do badly — so, can we transplant them with something that will increase the efficacy of the treatment?” said Krishnan, associate director of the Division of Hematology & Hematopoietic Cell Transplantation.
Physicians look beyond age
“There has been a lot of literature about older patients, examining why they do less well in cancer therapies,” Krishnan explained. “Is it because we’re afraid to give it to them? Can’t they tolerate it? Is their disease more aggressive?”
The group’s study, published in the Jan.1 issue of the Journal of Clinical Oncology, showed that older patients can successfully undergo transplants if they have good functional status: in other words, they can perform normal daily activities to meet their basic needs and maintain health. That means their “physiologic age” is more important than the number of candles on their birthday cake.
Physicians today use hematopoietic cell transplantation, or HCT, to treat a patient's malignancy or to repair diseased or defective bone marrow. These transplanted hemopoietic (blood) stem cells can come from patients themselves or matching donors.
HCT starts with a conditioning regimen, in which chemotherapy is used — with or without radiation therapy — to kill many of the cancerous cells riddling the body. After the conditioning regimen, patients receive infusions of replacement stem cells. These new cells give rise to the patient’s new immune system.
A gentler approach
City of Hope researchers’ new strategy includes a more intense, high-dose conditioning regimen but without increased toxicity, which can often come from total body irradiation (administering beams of radiation across nearly the whole body). Besides a group of four powerful anti-cancer drugs, it includes a radioimmunotherapy drug called Zevalin, which consists of tiny, engineered antibodies that carry radioactive isotopes directly to cancerous cells.
In the group’s clinical trial of more than 40 patients, the typical patient was 60 years old while the oldest was 78 (and is now 81). Researchers found that patients tolerated the addition of Zevalin to the treatment and had side effects comparable to those among patients taking the chemotherapy combination alone. Patients’ outcomes were promising enough to warrant more study, Krishnan said.
Results are especially encouraging for patients with diffuse large cell lymphomas, she added. Researchers will next look at the regimen’s effectiveness against certain types of lymphoma to see if it’s more successful than the traditional approach.
“This has become a regimen people are very interested in worldwide,” Krishnan said.