Healthy Living: Man's Worst Friend
There’s no shortage of information concerning prostate cancer—it’s all readily available at the American Cancer Society’s website cancer.org. It’s the second most common cancer diagnosis for American men (after skin cancer), and the second leading cause of cancer deaths in men (after lung cancer).
Roughly one in six of them will be diagnosed with the disease, with 241,740 new cases in 2012 alone. Nearly 30,000 men will die of prostate cancer this year, but because the disease is often slow to develop, many more—2.5 million—continue to live with it long after diagnosis. “We know that the majority of men with the disease aren’t going to die of it,” says Dr. Joseph R. Wagner, urologic oncologist with Hartford Specialists and director of robotic surgery at Hartford Hospital.
In part, this is due to the cancer’s reputation as an “old man’s disease”: The average age at diagnosis is 67, and 80 percent of men over 80 have it. The older you are at the time of diagnosis, the more likely you are to die of something else, like diabetes or heart disease. But this doesn’t mean younger men are free of risk. “When autopsy studies are done, it’s found that 30 percent of men age 50 harbor prostate cancer,” says Wagner.
For all that we know about prostate cancer, there’s also no shortage of mystery surrounding the disease. One of the thorniest problems has been how to achieve a reliable diagnosis, especially since symptoms are usually nonexistent. Toward that end, PSA screening, developed in the 1990s, was an important breakthrough. It’s a blood test designed to measure prostate-specific antigen, an enzyme produced by the prostate that enhances reproductive function. Screening determines its presence in terms of nanograms per milliliter: Levels tend to rise with the presence of prostate cancer, but also with benign conditions such as enlargement and inflammation of the prostate. A PSA below 4 is considered normal for most men, though men under 40 generally have PSAs less than 2.5 and in older men (above 70) higher levels may be acceptable.
So it’s an imperfect tool that sometimes results in confounding false positives, but it still—particularly when used in conjunction with a digital rectal exam (DRE)—“gives us our best chance of finding prostate cancers earlier than we have in the past,” says Dr. Marlene Murphy-Setzko, practitioner with the Hartford Urology Group and lead urologist at Saint Francis Hospital’s Curtis D. Robinson Men’s Health Center. “Before the PSA, we used to find 25 percent of our prostate cancer patients after the disease had metastasized to the bones. Now, only 5 percent of patients present at that stage.”
Annual PSA screenings in men age 50 and over (40 and over for African-American men and those with a family history of the disease) are currently covered by most insurance plans and Medicare. But in May of this year, the U.S. Preventive Services Task Force (USPSTF)—which describes itself in part as “an independent panel of experts that systematically reviews the evidence for effectiveness and develops recommendations for clinical preventive services”—gave the PSA test a barely passing “D” grade for diagnostic value, charging that it results “in small or no reduction in prostate cancer-specific mortality and is associated with harms related to subsequent evaluation and treatments, some of which may be unnecessary.”
Urologists cried foul, claiming that in making its determination, the USPSTF relied on two large cancer studies in the United States and Europe that had been heavily criticized. “This grade means that the PSA shouldn’t even be discussed between a doctor and a patient as a possible option,” says Murphy-Setzko. “Unfortunately, Medicare and other insurance providers tend to follow these task-force recommendations, potentially making the test non-reimbursable.” Adds Wagner, “To suggest the test is not worthwhile doesn’t seem logical, given that prostate cancer deaths have dropped since the introduction of PSA screenings in the 1990s and there are no other reasonable explanations.”
But the task-force evaluation speaks to a bigger issue, the tendency—particularly among U.S. doctors—to “overtreat” prostate cancer. “People who have been diagnosed are typically treated for the cure, even when there’s a good chance that the disease would not have been life-threatening,” says Dr. Peter G. Schulam, chairman of the department of urology at Yale School of Medicine and chief urologist at Yale-New Haven Hospital. “In many aspects of medicine, as long as the cure doesn’t harm, it’s okay to overtreat. But with prostate cancer, the primary treatments—surgery (radical prostatectomy) and radiation—can cause serious problems for the patient, including incontinence and impotence.”
How does a doctor best determine which patient has aggressive prostate cancer, which needs immediate intervention, and who has the slower-growing, non-life-threatening kind? On this question, too, there is no foolproof road map . . . yet. “The holy grail right now is to find a ‘marker’ that would indicate a bad cancer that needs treatment,” says Wagner. Notes Dr. Jeffrey D. Small, urologist and attending physician at St. Vincent’s Medical Center and Bridgeport Hospital, “The hottest research along these lines right now is in the area of epigenetic testing of prostate biopsy specimens.”
In the absence of a dependable marker, doctors are turning more and more to a protocol called “active surveillance,” in which a tumor, once detected, is “watched” for changes that might indicate increased threat. PSA levels play an important role in this process—are they going up over time?—as do their relationship to a man’s age (a PSA score of 6 in a man 75 years of age is considered less serious than in a man of 50). Other important sources of information, taken from a biopsy specimen, are the Gleason score (based on the tumor cells’ microscopic appearance) and the clinical stage of the disease (from T1 to T4, assigned based on the perceived size of the tumor and whether or not the disease has spread). Says Schulam, “If it looks like the cancer is progressing, we’ll intervene before it becomes metastatic.
“One problem in the process of active surveillance is that it’s very difficult to detect prostate cancer by imaging, because ultrasound is not very effective,” he adds. Ultrasound is typically used to guide prostate biopsy, in which needles are sent randomly into 12 or more different areas of the prostate, and the volume of the disease is determined by how many of these samples come back positive for cancer. Schulam notes that Yale is developing a system whereby an MRI image can be fused with real-time 3-D ultrasound—through a device called Artemis—which would make targeted biopsies possible.
Of course, active surveillance (instead of more aggressive treatment) can be put into play only if a patient agrees to it. “Unfortunately, there are guys who will tell you, ‘There’s no way I’m doing nothing—I’ve been afraid of getting cancer since I was a kid and I’ve been popping Valium like M&M’s since my diagnosis,’” says Wagner. “Many are worried they will miss a window of opportunity. But among our patients, only 25 to 33 percent on surveillance ultimately need treatment, and it is very seldom that they miss that window.”