WEDNESDAY, Nov. 2, 2011 (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.
For more on prostate cancer, visit the American Cancer Society.