Targeted Cancer Treatment Effective in Older Patients
Patients over 50 make up the bulk of those diagnosed with cancer. Yet these patients are often considered too old and frail for potentially lifesaving treatments such as bone-marrow transplants, says John Pagel, a blood cancer specialist at the Fred Hutchinson Cancer Research Center in Seattle.
“If we could get enough therapy into people, we could cure them,” says Pagel, who presented early results of experimental treatments Monday at the annual meeting of the American Society of Hematology in Atlanta.
Pagel and others are experimenting with methods that “target” cancer cells more precisely. His team focused on patients 50 and older who had either acute myeloid leukemia or high-risk myelodysplastic syndrome, a condition that often leads to cancer. Other Seattle researchers presented a study of patients over 60 with lymphoma, a cancer of the lymph nodes.
Instead of exposing the body to a wide beam of radiation, which can injure vital organs, scientists in each case attached radioactive particles to man-made versions of immune system proteins called antibodies, says Ajay Gopal of the University of Washington in Seattle. The antibodies were engineered to stick only to the types of white blood cells that are afflicted by these cancers.
That brings radiation directly to tumor cells but mostly spares other parts of the body, Gopal says.
Because doctors targeted cancerous tissue, they were able to give much stronger doses, Gopal says. In his study, 56% of patients are alive after three years. In Pagel’s study, about 55% are alive after about 10 months. Without treatment, all of the patients were expected to die from their disease, Pagel says.
Doctors didn’t compare the new treatments with other therapies, so they can’t say that the new strategies are superior, says Thomas Shea, director of bone-marrow transplantation at the University of North Carolina Lineberger Comprehensive Cancer Center in Chapel Hill, who did not work on the study. Although larger studies are needed to confirm the findings, Shea says, they are encouraging. “Not only can older patients tolerate these treatments well, but they had a good response.”