'Mini-transplant' patients' outcomes similar using related and unrelated donor cells

December 03, 2007

SEATTLE - People who undergo nonmyeloablative stem-cell transplants, or "mini transplants," for leukemia, lymphoma and other blood cancers have comparable outcomes regardless of whether they receive tissue-matched stem cells from a related or unrelated donor, according to new findings by researchers at Fred Hutchinson Cancer Research Center.

The research by Marco Mielcarek, M.D., and colleagues in the Hutchinson Center's Clinical Research Division appear in the December issue of the journal Biology of Blood and Marrow Transplantation.

"The main message for referring physicians is that if the patient is a candidate for a nonmyeloablative, or mini, transplant but does not have a suitable related donor, the transplant should not be delayed provided a matched unrelated donor is available," said Mielcarek, the lead author of the paper.

This is a significant finding because historically, "standard" (myeloablative) stem-cell transplants from unrelated matched donors have been associated with increased risk of non-relapse mortality and decreased overall survival compared to transplants from matched related donors. Only 30 percent of patients with hematologic malignancies who might benefit from a stem-cell transplant have a matched related donor.

The combination of immunosuppressive drugs and the unique biology of the mini transplant may be the reasons behind the research results, Mielcarek said.

The Hutchinson Center's pioneering development 10 years ago of the mini transplant, a kinder, gentler treatment that doesn't require the intensive radiation and chemotherapy associated with standard stem-cell transplants, made the therapy available to thousands of older patients who were medically unable to withstand the rigors of traditional transplantation.

Such transplants do not require a patient's marrow be destroyed with high-dose radiation and chemotherapy prior to the infusion of donor cells. The technique involves minimal radiation and substantially reduced side effects. The procedure often can be performed in an outpatient clinic.

Mielcarek and colleagues conducted a retrospective study of 221 patients who had matched related donors and 184 patients who had matched unrelated donors. All of the patients underwent mini transplants at the Hutchinson Center between December 1997 and June 2006. After adjusting for confounding factors such as comorbidities, relapse risk, patient age, stem-cell source, preparative regimen, and sex mismatch of donor and recipient, researchers found no statistically significant differences between patients who received unrelated and related matched donor cells in terms of rates of non-relapse mortality, relapse-related or overall mortality. Additionally, overall rates of severe acute and extensive chronic graft-versus-host disease between the two groups were not significantly different.

The preparative regimen for and the immunobiology of nonmyeloablative transplantation may account for the similar outcomes, according to the study. Patients who undergo mini transplants receive potent pre- and post-transplant immunosuppression drugs. This allows a major reduction in pre-transplant chemotherapy without compromising engraftment of the donor cells.
-end-
The paper was supported by grants from the National Institutes of Health.

Note for media only: The research paper, "Comparable Outcomes after Nonmyeloablative Hematopoietic Cell Transplantation with Unrelated and Related Donors" by Mielcarek and colleagues is available at the journal's Web site, http://www.bbmt.org/current.

At Fred Hutchinson Cancer Research Center, our interdisciplinary teams of world-renowned scientists and humanitarians work together to prevent, diagnose and treat cancer, HIV/AIDS and other diseases. Our researchers, including three Nobel laureates, bring a relentless pursuit and passion for health, knowledge and hope to their work and to the world. For more information, please visit fhcrc.org.

Fred Hutchinson Cancer Research Center

Related Chemotherapy Articles from Brightsurf:

Chemotherapy is used to treat less than 25% of people with localized sarcoma
UCLA researchers have found that chemotherapy is not commonly used when treating adults with localized sarcoma, a rare type of cancer of the soft tissues or bone.

Starved cancer cells became more sensitive to chemotherapy
By preventing sugar uptake, researchers succeeded in increasing the cancer cells' sensitivity to chemotherapeutic treatment.

Vitamin D could help mitigate chemotherapy side effects
New findings by University of South Australia researchers reveal that Vitamin D could potentially mitigate chemotherapy-induced gastrointestinal mucositis and provide relief to cancer patients.

Less chemotherapy may have more benefit in rectal cancer
GI Cancers Symposium: Colorado study of 48 patients with locally advanced rectal cancer receiving neoadjuvant chemotherapy, found that patients receiving lower-than-recommended doses in fact saw their tumors shrink more than patients receiving the full dose.

Male fertility after chemotherapy: New questions raised
Professor Delb├Ęs, who specializes in reproductive toxicology, conducted a pilot study in collaboration with oncologists and fertility specialists from the McGill University Health Centre (MUHC) on a cohort of 13 patients, all survivors of pediatric leukemia and lymphoma.

'Combo' nanoplatforms for chemotherapy
In a paper to be published in the forthcoming issue in NANO, researchers from Harbin Institute of Technology, China have systematically discussed the recent progresses, current challenges and future perspectives of smart graphene-based nanoplatforms for synergistic tumor therapy and bio-imaging.

Nanotechnology improves chemotherapy delivery
Michigan State University scientists have invented a new way to monitor chemotherapy concentrations, which is more effective in keeping patients' treatments within the crucial therapeutic window.

Novel anti-cancer nanomedicine for efficient chemotherapy
Researchers have developed a new anti-cancer nanomedicine for targeted cancer chemotherapy.

Ending needless chemotherapy for breast cancer
A diagnostic test developed at The University of Queensland might soon determine if a breast cancer patient requires chemotherapy or would receive no benefit from this gruelling treatment.

A homing beacon for chemotherapy drugs
Killing tumor cells while sparing their normal counterparts is a central challenge of cancer chemotherapy.

Read More: Chemotherapy News and Chemotherapy Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.