Get Your Stem Cell Tune Up

Mini transplant of stem cells well tolerated in older patients with blood cancers

(RxWiki News) As a patient gets older, the number of treatments available becomes limited. Luckily for older patients with blood cancers, age is not a factor in getting a stem cell transplant.

Researchers at the Fred Hutchinson Cancer Research Center have discovered that the “mini-transplant,” they call a “gentler” donor cell stem cell transplant, is well tolerated in older patients who have several types of blood cancer. This could open the door for stem cell transplants becoming a viable option for older individuals.

"Older blood cancer patients have new options that improve survival."

Blood cancers such as leukemia and lymphoma affect how the body creates healthy blood cells. The bone marrow is damaged which then leads to excessive bleeding, frequent infections and anemia. Stem cell transplantation is dangerous for older patients because of the intense chemotherapy needed to kill off leukemic cells.

Stem cells and bone marrow transplants are then infused back into the body replacing the destroyed blood and restoring the immune system.

The mini-transplant delivers lower doses of chemotherapy and does not kill off all the bone marrow. It hinders the immune system allowing for the donor cells to kill off cancer cells and help restore the immune system.

In the study, 372 patients separated into three age brackets, 60 to 64, 65 to 69 and 70 to 75, were enrolled in a clinical trial from 1998 to 2008. Each age group had similar survival rates, 35 percent for overall survival after five years and 32 percent disease-progression free survival after five years.

While these survival rates may seem low, according to one of the authors of the study, Mohamed Sorror, M.D., M.Sc., an assistant member of the Hutchinson Center's Clinical Research Division, many would have died after just a few months without the transplant.

Many of the patients had tried all other conventional therapies before undergoing stem cell transplantation. Pre-existing diseases and the aggressiveness of the cancer affected survival the most.

After the transplant, most patients had near-normal levels of performance when it came to rate of relapse, hospitalization and damage to internal organs. Even a common side effects such as chronic and acute graft vs. host disease (GVHD) could be managed. GVHD is when the transplanted donor cells attack the host's own cells.

For two-thirds of the patients who suffered from chronic GVHD after the transplant, they were able to stop using immunosuppressive treatments after two and a half years. This number was similar to a previous study involving younger patients who were treated with high doses of radiotherapy and chemotherapy.

The next step for researchers is directing patients to the mini-transplant as a treatment option. Additional studies comparing a mini-transplant to conventional treatments will also be necessary.

This study was published in the November edition of the Journal of American Medical Association.

Review Date: 
November 3, 2011