My dad worries. Mostly about his wife, two daughters and aging Labrador, but every now and then, thoughts turn to himself. His mother beat colon cancer, his brother died from pancreatic cancer, so he takes signs and symptoms seriously. That's why I was surprised when he casually mentioned his elevated prostate-specific antigen (PSA) level.
The PSA test was part of a routine exam conducted at the firehouse, where he's volunteered for nearly 40 years. My dad's not keen on waiting in a doctor's office just to hear he should drop a few pounds, so the firehouse physical is an easy way to check in.
My dad's PSA had been high before; he got a biopsy 2 years ago, but--after much fretting--it came back negative. This time, his PSA was even higher, but he wasn't concerned. The test has a reputation for faulty results (both healthy and cancerous cells can produce the chemical), so my dad was confident he was cancer-free.
Then he got the call. The urologist apologized for having to tell my dad over the phone, but even he was surprised by the results. Turns out, my dad had early stage prostate cancer--about as early as you can catch it. There was no immediate danger, but my dad decided to undergo surgery.
Some would consider his actions smart; others, excessive. That's because PSA testing isn't fool-proof. Doctors often err on the side of caution, but research findings have patients questioning whether the test is worth it.
Behind the Controversy
The PSA test has been criticized for inducing Henny Penny panic in men when results are abnormal. Even when a biopsy confirms the diagnosis, it's not always a death knell; some forms of prostate cancer never progress, or grow at such a slow pace they never become life-threatening, according to research. The European Randomized Study of Screening for Prostate Cancer (ERSPC) found that PSA screening every 4 years reduced prostate cancer deaths by 20 percent; however, the test also led to overdiagnosis, with 48 additional cancers detected for every death prevented. Similarly, the National Cancer Institute's Prostate, Lung, Colorectal and Ovarian Cancer (PLCO) Screening Trial identified "excess" cancer diagnoses--the screening group had 23 percent more diagnoses than the control group. But unlike the ERSPC, the PLCO trial did not find any reduction in deaths as a result of screening.
The results prompted some skeptics to slough off the test, but Mark Kawachi, MD, chair of the National Comprehensive Cancer Network Guidelines for Prostate Early Detection, believes early detection shouldn't be understated.
"I don't think anybody would be willing at this point in time to simply turn ther back on PSA, because it is in the single most powerful blood test for identifying the presence of prostate cancer at a time when the cancer is curable," said Kawachi, who is also associate professor of surgery, urology and urologic oncology at City of Hope Comprehensive Cancer Center, Duarte, CA.
The problem isn't overdiagnosis, Kawachi said, it's overtreatment. PSA testing and biopsies can confirm a man has cancer, but they can't distinguish between life-threatening and non-threatening cases. Large population studies, like the ERSPC and PLCO, indicate that more often than not, the cancer will be too slow-growing to prove fatal. But when you're the one on the exam table, numbers provide little comfort.
"We know some men will die, we know some men won't die, but we can't apply the statistics to a particular patient and necessarily say it's cut-and-dry this is what you should do," Kawachi said.
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