Researchers found that more than 500 men with cancer -- including cancers caught through regular screening -- ended up with poorer sexual function and more bladder control problems for up to 10 years afterward than men with no cancer diagnosis.
That might sound like a good trade-off for having your cancer found and treated.
But the issue is complicated. Prostate cancer is often slow-growing and may never get to the point that it threatens a man's life.
And a number of studies have found no proof that using prostate-specific antigen (PSA) blood tests to screen men for prostate cancer actually saves lives.
Because of that the U.S. Preventive Services Task Force (USPSTF) -- an expert panel with federal support -- advises against routine prostate cancer screening.
With the benefits of screening in doubt, that makes the question of treatment side effects even more important.
"The reality is that right now, the screening decision and the treatment decision have to be made on an individual basis," said Kathryn L. Taylor, of the Lombardi Comprehensive Cancer Center at Georgetown University in Washington, DC.
"This study doesn't answer those questions for individuals," said Taylor, who led the research.
But she said the findings do give men more information on the long-term side effects of prostate cancer treatment -- whether it's surgery, radiation, or hormone therapy.
Up to 10 years after treatment, more than 95% of men had some degree of sexual dysfunction, Taylor's team found. And about half had urinary symptoms.
Past studies have found such lingering side effects, too. But they have been shorter-term -- following men for as far as five years. And they've left some question as to whether the sexual and urinary problems could just be a product of aging, rather than prostate cancer treatment, Taylor explained.
These latest findings, reported in the Journal of Clinical Oncology, suggest it's not simply the aging process that's to blame.
That's because Taylor's team had data on men who'd taken part in a large clinical trial on prostate cancer screening.
The researchers were able to compare 269 men who'd had prostate cancer detected and treated after screening with 260 men who'd also been screened but remained cancer-free.
And when they accounted for the men's age, overall health, and other factors, the group treated for cancer had worse sexual and urinary function up to 10 years later.
The same pattern held up among men in the trial arms who weren't screened for prostate cancer and did or didn't get diagnosed and treated.
That all suggests the blame lies with prostate cancer treatment, or possibly the cancer itself to some degree, according to Taylor.
"The bottom line is that the (prostate cancer) group was worse off," Taylor said. And that's something men should have in mind when deciding on prostate cancer screening, she and her colleagues say.
Once prostate cancer is detected, men have another big decision. If the cancer is early-stage, they can choose to put off treatment and instead have the cancer monitored to see if it's progressing -- what doctors call "active surveillance."
Or they can go for treatment, with surgery being the usual option for earlier cancer.
"We like to tell men to think of it as one big question," Taylor said.
That is, don't think of the screening decision in isolation, she explained. Men should remember that if an early cancer is caught, they'll have to decide on treatment, Taylor said.
Active surveillance, by definition, is not treatment -- but it does mean regular PSA blood tests and periodic biopsies.
The USPSTF recommendation against routine prostate cancer screening does not preclude men from asking for it, or doctors from offering.
And Taylor pointed out that studies look at population-wide effects. Even if PSA screening has not cut overall death rates from prostate cancer, some men may benefit.
She suggested men "get educated" about prostate cancer and make a screening decision based on a careful discussion with their doctors.
In the U.S., just over 28,000 men will die of prostate cancer this year, according to the American Cancer Society. But close to 242,000 new cases will be diagnosed, many of which will be early cancers.
According to the National Cancer Institute, about half of all U.S. men diagnosed with prostate cancer in 2009 fell into the "low-risk" category -- meaning their cancer was unlikely to progress.
By Amy Norton
Journal of Clinical Oncology, online June 25, 2012.
Last Updated: 2012-06-27 11:35:06 -0400 (Reuters Health)
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