Special
to
Campus News by Eileen Korey,
director of news services, University
Hospitals of Cleveland
High-dose chemotherapy coupled with a stem cell transplant do not
improve the outcomes of post-operative patients with advanced breast
cancer, according to findings of a multi-center study designed and
conducted at the Ireland Cancer Center at University Hospitals of Cleveland
(UHC) and Case Western Reserve University School of Medicine (CWRU).
The study appeared in the July 3rd issue of the New England Journal
of Medicine. The findings should alter the treatment approach for patients
with primary breast cancer that has spread to the regional lymph nodes,
according to Hillard M. Lazarus, MD, director of the Blood and Marrow
Transplantation Program at UHC and professor of medicine at CWRU. Lazarus'
co-senior author on the Eastern Cooperative Oncology Group (ECOG) coordinated
study was Martin S. Tallman, M.D. of the Robert H. Lurie Comprehensive
Cancer Center of Northwestern University.
"We found that an autologous stem cell transplant-high-dose chemotherapy
followed by either bone marrow or blood from the patient herself-did
not significantly increase the survival rate of women with early stage
breast cancer that had spread to at least 10 lymph nodes in the axillary
(arm pit) area," Lazarus said. "These results have enhanced
our understanding of the disease and motivate us to explore alternatives
to stem cell transplantation. It is evident that high dose chemotherapy
destroys more cancer cells, but its complications can also be deadly
to patients. We need to look at what we've learned about high dose
chemotherapy and transplantation through this study, and use it as
a platform on which to build similarly strong, yet safer treatments."
Nationwide, Lazarus and his colleagues studied 511 primary breast
cancer patients whose tumors had spread to at least 10 lymph nodes
under the arm. Half of the group was treated with conventional chemotherapy-only
for six months-and the other half received the identical chemotherapy
followed by high-dose chemotherapy and a stem cell transplant. All
patients received the conventional dose of three drugs: cyclophosphamide,
doxorubicin and fluorouracil. The high-dose chemotherapy consisted
of cyclophosphamide and thiotepa.
Although there were many fewer relapses in the patients assigned to
receive an autograft, the overall results showed that there was no
significant difference in survival rates between the two groups. However,
nine of the 511 patients died of transplantation complications. Nine
others developed myelodysplastic syndrome (a pre-leukemia condition)
or acute myeloid leukemia.
The procedure combines the administration of high doses of chemotherapy
with the transplantation of stem cells from the patient's own blood
or bone marrow. High-dose chemotherapy kills healthy blood cells as
well as cancer cells, so stem cells are transplanted to restore the
patient's blood production. The infused stem cells regenerate white
blood cells to fight infection, red blood cells to carry oxygen and
platelets that enable blood to clot.
These stem cells, taken from the patient's body (autologous) or from
another person (allogeneic), are infused through a vein and travel
to bone marrow to produce new white blood cells, red blood cells and
platelets, enhancing the patient's health.
This life-saving treatment has been used successfully for more than
25 years to cure various types of leukemias and lymphomas. More recently,
the treatment has proven effective for patients with multiple myeloma
(bone cancer) and certain non-malignant disorders.
In the last decade, this modality was used with promising results
in women with breast cancer whose prognosis is poor. Only 20 to 30
percent of such women with high-risk breast cancer are cancer-free
five years after surgery.
In the 1980s and 1990s, some researchers found high-dose chemotherapy
and autologous transplantation to be a promising therapy for breast
cancer patients at high risk for relapse.
In a separate study in the same issue of the New England Journal of
Medicine, researchers at the Netherlands Cancer Institute concluded
that there is a benefit to high dose chemotherapy and transplant, with
a 10 percent greater relapse-free survival among women who received
the high-dose approach versus conventional therapy. This benefit was
most evident among women under 40 years old with HER2/neu negative
tumors (breast cancers that exhibit less aggressive features).
It should be noted that the chemotherapy regimens used in both studies,
designed and activated more than a decade ago, differ from current
conventional and high-dose chemotherapy approaches used in many cancer
centers today. Moreover, Lazarus said he remains concerned about the
secondary cancers and complications associated with high-dose treatments
analyzed in this study.
"Conventional-dose chemotherapy remains the standard of care
for most breast cancer patients who are at high risk for relapse due
to lymph node involvement," he said. "But blood stem cell
or bone marrow transplantation
Return
to the online edition of the 7-24-03 Campus News.