WEDNESDAY, Nov. 2 (HealthDay News) -- A combination of radiation
and hormone therapy prolongs survival among men whose cancer has
spread beyond the prostate, Canadian and U.K. researchers
report.
These men have what is called high-risk, or locally advanced,
prostate cancer. Among men with prostrate cancer, up to 25 percent
fall into this category. In the past, these men have often been
treated with hormone therapy alone, the researchers noted.
"In patients with locally advanced prostate cancer, combining radiation therapy plus hormonal therapy gives much better results than hormone therapy alone," said lead researcher Dr. Padraig Warde, deputy head of the Princess Margaret Hospital Cancer Program and a professor of radiation oncology at the University of Toronto.
"Specifically, it reduces the risk of dying from prostate cancer 43 percent and the risk of dying overall by 23 percent," he said, adding that this is the first study that shows that the combination of radiation and hormone therapy improves survival.
"These patients were often felt, in the past, to be incurable, because the disease has spread locally outside of the prostate, but not elsewhere in the body," he said. "But they shouldn't be discarded, we are showing that going for a cure is worthwhile."
Treatment options for patients with locally advanced prostate
cancer are limited, Warde said. Most of these patients are not
candidates for surgery because of the size of their tumors, he
said.
The report was published in the Nov. 3 issue of
The Lancet.
For the study, Warde's team randomly assigned more than 1,200
men with high-risk prostate cancer to hormone therapy alone or in
combination with radiation.
After seven years, 66 percent of men who had hormone therapy
alone were still alive, compared with 74 percent who received both
hormone and radiation therapy. In the group of men who had hormone
therapy alone 26 percent died from prostate cancer, compared with
10 percent who had combination therapy, the researchers found.
Warde noted that while men had the predicted side effects of
hormone therapy, such as erectile dysfunction, hot flashes and mood
swings, the addition of radiation did not affect overall quality of
life three years after treatment.
When the study began in 1995, the protocol was to use hormone
therapy for life, and radiation was given in lower doses, but not
as precisely directed as it is today, Warde said. Currently,
hormone therapy is used for a shorter time, usually two to three
years, and radiation is given in higher doses but more specifically
targeted to the tumor.
"There is reason to think that with modern radiation approaches that the results would be much better," he said.
Prostate cancer expert Dr. Anthony D'Amico, chief of radiation
oncology at Brigham and Women's Hospital in Boston, said that "this
doesn't change practice, because we already do this, but it's a
validation that you cannot leave out one or the other treatment
when treating someone with locally advanced disease."
Dr. Matthew R. Cooperberg, an assistant professor of urology at
the University of California, San Francisco, and author of an
accompanying journal editorial, said that "high-risk disease needs
to be treated aggressively."
However, this study doesn't determine what is the best treatment
for high-risk prostate cancer, Cooperberg said. "There are studies
showing that the best treatment for high-risk disease starts with
surgery and then radiation and hormones as necessary," he
noted.
"Men with high-risk disease need multi-modal therapy," Cooperberg said. "Whether the approach should be surgery possibly followed by radiation, is still the big open question that we need to answer."
These patients are not candidates for what is called active
surveillance, where doctors wait for the disease to advance before
treating it, Cooperberg said.
Cooperberg also noted that the urinary side effects from
radiation are not as mild as the study suggests, and can, for some
patients, be severe.
More information
For more on prostate cancer, visit the
American Cancer Society.