Radiation Urged for Recurring Prostate Cancer
Researchers say it should begin at first sign after surgery
TUESDAY, March 16, 2004 (HealthDayNews) -- Thousands of lives could be saved each year if doctors moved swiftly to give radiation treatment to men at the first sign that prostate cancer was returning after surgery, a study finds.
"About 30,000 men a year experience recurrence and half of them die," says study leader Dr. Kevin M. Slawin. "I would estimate that 5,000 to 10,000 of them could be saved."
The crucial sign of recurrence is a rise in blood levels of prostate-specific antigen (PSA), a protein related to prostate cancer, says Slawin, a professor of urology at the Baylor College of Medicine in Houston.
"After an operation, the PSA level should be zero," he says. "If it starts going up, you have recurrence. That's when radiation therapy should be started."
Radiation therapy now is underused by many cancer doctors, Slawin says. "They don't think it works, so they just give hormone therapy."
To show that radiation therapy could save lives, Slawin and his colleagues studied 501 patients at five medical centers who were given radiation therapy when there were signs their cancers had returned after surgery.
Most of those patients would be regarded as incurable by widely used standards, the researchers say. But the study shows the tumor could be stopped when radiation therapy was given early enough, Slawin says.
While PSA levels are the most critical factor, the study included a number of other measures, such as the Gleason score, a measure of tumor's aggressiveness; the presence or absence of malignant cells at the edges of the removed tissue; and the time during which the PSA levels doubled.
"All these variables influence outcome," Slawin says. "We are developing a nomogram [model] in which you can put in all the variables and come out with a precise cure rate. It will be published in the not-too-distant future."
Widespread use of that model could save up to 15,000 lives a year, estimates Dr. Mitchell S. Anscher, a professor of radiation oncology at Duke University Medical Center, who wrote an accompanying editorial.
"All this information is routinely available for every patient," Anscher says. But the problem is that many physicians don't act quickly enough in starting radiation therapy, he says.
"In reality, what they tend to do is wait, unless there was some bad feature in surgery," Anscher says.
Men who have had surgery for prostate cancer should be aware of the study and its implications for themselves, he says.
"Patients should be aware of what their PSA level is," Anscher says. "You need to be an advocate for yourself in this situation, to be aggressive in getting information. If a recurrence is detected early, a significant fraction of these men are potentially curable."