SCCA pioneers new transplant procedures to reduce need for matching bone marrow donors

Apr 19 2013

Patients from ethnic minority and mixed-racial backgrounds are less likely to receive a lifesaving bone marrow transplant than Caucasian patients with the same disease due to lack of matching donors, according to the National Marrow Donor Program (NMDP).

The likelihood of a patient finding a bone marrow donor match is highly dependent on genetic similarities between the patient and donor. Seventy percent of patients in need of a transplant do not have a matching donor in their family, according to Be The Match, operated by the NMDP. These patients must instead turn to a donor registry or alternative methods for treatment. Unfortunately, few minority patients have either a matched family member or an identified matched unrelated donor. This is due to complex genetic factors and low donor-registration numbers.

Seattle Cancer Care Alliance (SCCA) is working with Fred Hutchinson Cancer Research Center to pioneer new lifesaving transplant procedures to reduce the need for matching bone marrow donors by providing bone marrow or blood stem cell transplants to patients who would not typically be candidates due to lack of a matching donor.

"The striking difference in donation levels echoes the need to raise awareness of the bone marrow and umbilical cord blood donation registries, while continuing the development of transplant programs that expand the availability of these life-saving treatment to more people," said SCCA's Colleen Delaney, M.D., MSc, director of the Cord Blood Transplant Program and associate member of the Clinical Research Division at Fred Hutch. "Thanks to innovative treatments developed at Fred Hutch and available today through the SCCA Transplant Program, nearly all patients in need of a bone marrow or blood stem cell transplant will be able to identify a donor. Our goal is to make sure every patient who needs a blood stem cell transplant will get one with survival rates that are equivalent to conventional unrelated donors."

Delaney is a renowned expert in the development of novel methods to grow cord blood stem cells in the laboratory and has pioneered steps toward reducing the risk of life-threatening infections in patients who receive a cord blood transplant.

Cord blood is unique from other sources of stem cells for bone marrow transplants. This leftover blood in the umbilical cord, which is collected immediately after birth without harm to the infant or mother, contains immune cells that are protected from foreign invaders such as bacteria and viruses. Due to this protection, these "naive" immune cells do not perceive a patient's unmatched stem cells as a threat. This means cord blood transplants do not require a near identical genetic match between donor and patient for successful treatment. Most cord blood transplants involve a genetically mismatched donor and patient.

While cord blood transplant recipients have been at high risk for early post-transplant complications due to the low number of cells available in a single cord blood unit, Delaney's innovative methods for expanding the number of cord blood cells per unit prior to transplant have been able to reduce such risks.

Jessie Quinn, a patient of half-Caucasian and half-African American ancestry, knows first-hand the lifesaving promise of expanded cord blood cells method. A survivor of acute myelogenous leukemia (AML), Quinn was the first patient to participate in an SCCA clinical study led by Delaney using her novel approach with expanded cord blood cells. Quinn credits her survival to the Fred Hutchinson Transplant Program at SCCA and her doctors' dedication to developing innovative options for patients unable to find a donor match.

The Fred Hutchinson Transplant Program at SCCA also provides successful haploidentical transplants for patients unable to find a relative who is a perfect match. Led by Paul O'Donnell, M.D., Ph.D., medical director of SCCA's Adult Transplant Service and researcher in the Clinical Research Division at Fred Hutch, haploidentical transplants are performed when a patient's relative offers a partial donor match. Through advances in drug therapies, physicians are able to control the adverse immune system responses that previously prevented these partially matched relatives from serving as donors. Haploidentical transplants are especially beneficial for pediatric patients using their parents or siblings as donors.

"Patients should not give up hope if they run into difficulties finding a donor," O'Donnell said. "At SCCA, we are committed to turning cancer patients into cancer survivors. Sometimes that means exploring alternative options and looking into clinical trials to help our patients conquer cancer. The Fred Hutchinson Transplant Program at SCCA offers patients additional treatment plans when they often believe they are out of options."

O'Donnell is currently leading a multi-center, randomized clinical trial to determine the effectiveness of double unrelated umbilical cord blood transplants versus haploidentical related bone marrow transplants in people with leukemia or lymphoma. He is actively recruiting patients. A multi-center randomized Phase II study led by Delaney is also currently recruiting patients to evaluate the clinical efficacy of giving study participants umbilical cord blood cells that have been expanded in the laboratory to increase the number of cells available for the transplant.

SCCA has been at the forefront of revolutionizing transplant treatment options since the clinical use of bone marrow and stem cell transplantation was first developed at the Fred Hutch more than 40 years ago. One of its founders, E. Donnall Thomas, M.D., won the 1990 Nobel Prize in physiology or medicine for this groundbreaking work. As a result of Thomas' innovation, the world's millionth blood stem cell transplant procedure took place in January of this year. To date, SCCA's doctors have performed more than 14,000 bone marrow transplants and the clinic consistently ranks among the country's top transplant centers in one-year patient survival rates.

Fred Hutch continues to lead transplant research and has pioneered the use of transplants to treat autoimmune disorders and other, non-cancerous diseases. By developing "mini-transplants" that use minimal doses of radiation resulting in reduce side effects, older patients who were not previously eligible for transplants now have an additional treatment option.