Two Studies Say Senior Citizens Can Take Acute
Myeloid Leukemia Treatments
Chemotherapy and blood stem cell transplants okay
for treating elderly with common leukemia
Dec. 9, 2008 Although acute myeloid leukemia
usually strikes when people are about age 65, these senior citizens have
often been offered only supportive care because they are believed to be
too weak to withstand treatment. Two studies presented yesterday say
these elderly AML victims are not too old for chemotherapy or blood stem
cell transplants.
About 13,300 new cases of AML are expected this
year in the United States. It is a rapidly progressive disease that
results in the accumulation of immature, functionless cells in the
marrow and blood, leaving the body unable to fight infections or produce
enough normal red blood cells, white blood cells and platelets.
This type of cancer, the second most common form of
leukemia in adults, is rare under age 40. It generally occurs around age
65. AML is more common in men than women.
Blood Stem Therapy
Researchers from the Center for International Blood
and Marrow Transplant Research reported yesterday at the 50th annual
meeting of the American Society of Hematology on their study saying age
alone should not determine whether an older patient with acute myeloid
leukemia or myelodysplastic syndrome receives a blood stem cell
transplant from a matched donor.
Patients older than 65 do just as well as younger
patients with transplants that are preceded by a milder chemotherapy
regimen, according to an intensive analysis of every such transplant for
AML or MDS conducted in North America between 1995-2005, said senior
researcher Sergio Giralt, M.D., professor in The University of Texas M.
D. Anderson Cancer Center Department of Stem Cell Transplantation and
Cellular Therapy. The analysis also included international transplant
data.
The retrospective study of 551 transplants for MDS
and 565 for AML showed that age had no statistically significant impact
on transplant-related mortality, relapse, leukemia-free survival or
overall survival.
"These findings will be important in changing
practice for the treatment of older patients," Giralt said. "We also
hope the findings persuade the Centers for Medicaid and Medicare
Services to recommend coverage of this therapy for MDS patients, as it
does now for AML."
Acute myeloid
leukemia (AML) is cancer that starts inside bone marrow, the soft tissue
inside bones that helps form blood cells. The cancer grows from cells
that would normally turn into white blood cells.
Acute myeloid
leukemia (AML) is one of the most common types of leukemia among adults.
This type of cancer is rare under age 40. It generally occurs around age
65. (This article focuses on AML in adults.)
AML is more common
in men than women.
Persons with this
type of cancer have abnormal cells inside their bone marrow. The cells
grow very fast, and replace healthy blood cells. The bone marrow, which
helps the body fight infections, eventually stops working correctly.
Persons with AML become more prone to infections and have an increased
risk for bleeding as the numbers of healthy blood cells decrease.
Most of the time, a
doctor cannot tell you what caused AML. However, the following things
are thought to lead to some types of leukemia, including AML:
● Certain
chemicals (for example, benzene)
● Certain
chemotherapy drugs, including etoposide and drugs known as
alkylating agents
● Radiation
Problems with your
genes may also play a role in the development of AML.
You have an
increased risk for AML if you have or had any of the following:
● A weakened
immune system (immunosuppression)
due to an organ transplant
Findings were presented at the meeting Monday
morning by Dan McClune, D.O., of the University of Minnesota Masonic
Cancer Center Department of Leukemia.
Matched donor, or allogenic, blood stem cell
transplants originally were preceded with high-dose chemotherapy that
destroyed the patient's blood supply before transplant. For patients
over 65, this "myeloablative" chemotherapy was too toxic and therefore
outcomes were poor.
Giralt and colleagues at M. D. Anderson pioneered
the use of less-intensive chemotherapy that did not annihilate a
patient's blood supply. This "non-myeloablative" preparation opened the
door for older patients to receive the potentially curative transplants.
Still, some hesitancy has remained even for
non-myeloablative transplants for older patients. Lack of Medicare
coverage also reduces the number of patients who can receive the
treatment, Giralt said.
The research project divided patients into four age
groups: 40 to 54, 55-59, 60-64, and 65-plus. In addition to finding no
statistically significant difference in survival across age groups, the
researchers found no difference in acute or chronic graft-vs.-host
disease.
The two most important prognostic variables were
disease type and status of disease at transplant, which affected
survival in the first year, and affected transplant-related mortality
and relapse in the second year after transplant.
Giralt and Daniel Weisdorf, M.D., of the School of
Medicine at Washington University, designed and proposed the research
project to the Center for International Blood and Marrow Transplant
Research. The CIBMTR is a joint effort of all stem cell transplant
centers, which report their results to the center to facilitate research
such as this study.
Co-authors on the study with McClune, Giralt and
Weisdorf are John DiPersio, M.D., Ph.D. of Princess Margaret Hospital in
Toronto; Armand Keating, M.D., and Tanya Pederson of the CIBMTR in
Milwaukee; Gisela Tunes da Silva, Ph.D., of the Medical College of
Wisconsin; J. Sierra, M.D., of the Hospital De Sant Pau in Barcelona,
Spain; and Martin Tallman, M.D., of the Northwestern University Feinberg
School of Medicine.
The research was funded by the CIBMTR.
The University of Texas M. D. Anderson Cancer
Center in Houston ranks as one of the world's most respected centers
focused on cancer patient care, research, education and prevention.
Chemo Treatment with Decitabine
Also presented yesterday at the San Francisco
meeting were preliminary findings of a phase II study at The Ohio State
University Comprehensive Cancer Center James Cancer Hospital and
Solove Research Institute - suggest that older, previously untreated AML
patients can achieve complete remission at a higher than expected rate
when treated with the drug decitabine using a novel dosing schedule.
"This study could provide a new treatment paradigm
for elderly patients with AML," says co-author Dr. John Byrd, associate
director of translational research at Ohio State's Comprehensive Cancer
Center James Cancer Hospital and Solove Research Institute.
Most elderly AML patients diagnosed today are
offered only supportive care because their bodies are believed to be too
weak to withstand the effects of chemotherapy treatment, says principal
investigator Dr. William Blum, a hematologist and oncologist and
researcher at Ohio State.
"The treatment of AML is difficult in anybody, but
particularly for older patients who don't tolerate the 'thunderbolt' of
intensive chemotherapy well," says Blum.
"Some of the patients we are treating successfully
had previously been told by other physicians to 'go home and die.' They
were judged not to be candidates for any treatment at all because they
likely would not survive the traditional, harsh chemotherapy approach."
"The development of a less toxic therapy may enable
this 'silent majority' of patients who never receive treatment today to
actually benefit from prolonged remissions with improved quality and
length of life, without paying the price exacted by today's intensive
therapy regimens," says Blum.
This ongoing study involves 33 patients age 60 to
83.
A total of 58 percent of patients responded,
including 42 percent who achieved complete remission. In some cases,
Blum says, patients who achieved remission were then able to receive
bone marrow transplants designed to further improve their chances for
cure, as part of another clinical trial of transplantation specifically
designed for older AML patients.
On the decitabine trial, patients received the
intravenous drug for one hour a day for 10 consecutive days each month
until the leukemia was gone. Subsequent cycles of the drug were given
for three to five days, customized for each patient based on clinical
response or toxicity.
"Results have been extremely promising, with high
remission rates," says senior investigator Dr. Guido Marcucci, a
researcher and medical oncologist at Ohio State's Comprehensive Cancer
Center James Cancer Hospital and Solove Research Institute. "This
research reveals the potential for a paradigm shift in the treatment of
AML away from highly toxic drugs to a much less toxic alternative."
This study was supported by grants from the
National Cancer Institute and the D. Warren Brown Foundation.
Other Ohio State cancer researchers involved in
this study include Dr. Rebecca Klisovic, Shujun Liu, Dr. Ramiro Garzon,
Cheryl Kefauver, Zhongfa Liu, Jon Mickle, Hollie Devine, Dr. Steve
Devine, Dr. Michael R. Grever, Kenneth K. Chan, Dr. Miguel
Villalona-Calero.
The Ohio State University Comprehensive Cancer
Center-James Cancer Hospital and Solove Research Institute is one of
only 40 NCI-designated Comprehensive Cancer Centers in the United States
and the only freestanding cancer hospital in the Midwest. Ranked among
the top 20 cancer hospitals in the nation, The James is the 172-bed
adult patient-care component of the cancer program at The Ohio State
University.
Keep up with the latest news for senior citizens, baby
boomers
Dec. 9, 2008 Although acute myeloid leukemia
usually strikes when people are about age 65, these senior citizens have
often been offered only supportive care because they are believed to be
too weak to withstand treatment. Two studies presented yesterday say
these elderly AML victims are not too old for chemotherapy or blood stem
cell transplants.