Simpson tried to learn whether the gain for that group of people would be proportional to its price. When everything was added up, she concluded that a screening program would save society up to $3 billion over the lifetime of the present generation of older men.
"You get a little bit of life saved and a small amount of money saved per man screened," she told me recently, adding that benefits to individuals could of course be considerable.
I asked if that $3 billion savings merited investing in an enormous screening and treatment program for the whole country. Even in the most optimistic scenario the costs are high in the beginning, running to billions, and the benefits do not appear for years. "You'll spend more money each year until you find and treat all the cancers, and then you start saving money," she said. "The policy question is, can we afford to do that right now?"
What Men Should Do
IN some ways Simpson's question is moot. Although statistically each man obtains only a slight benefit from the test, those benefits are not distributed evenly - a man either receives them in full or he doesn't. The chances are quite good that if an otherwise healthy man who has just been diagnosed as having lowgrade prostate cancer ignores the news, his cancer will never trouble him and he will die of something else. Yet the penalty for guessing wrong is severe - and nobody plans to die of other causes. People focus on the problem at hand, and the argument that they should forget about prostate cancer because they might be felled by a stroke in five years carries little weight. As a result, men are willing to accept the possibility of deleterious side effects today to avoid an awful death in the future. Cost is rarely a factor to the individual, because his insurance will pick up most or all of the tab. On the broad societal level this may be the wrong choice, medically and fiscally. But the individual man doesn't care - his cancer will either stay dormant or kill him. As a result a de facto national screening program is taking place, good idea or no. Men are running pellmell to measure their PSA levels, and those with positive cancer diagnoses are submitting themselves to radical prostatectomy in record numbers. It is a perfect example of why healthcare costs are so difficult to control.
"What's good for the individual may not necessarily be good for the masses," Chodak told me. "It sounds like the moral of a Star Trek movie." Even William Catalona, a PSA enthusiast, would like to put some brakes on the prostatectomy express. Men over seventyfive should think twice about subjecting themselves to such a major surgical procedure as radical prostatectomy, he says. Even in the best of circumstances they are disproportionately likely to experience impotence and incontinence and to live no longer than they would have without the surgery. Therefore Catalona thinks the PSA test has considerably less utility for such men. Like every other researcher I have spoken with, he is dismayed by the recent explosion in prostate surgery in men older than seventyfive.
Fifty to sixtyyearolds, though, are a different matter. Both sides, pro and con, believe that if benefits accrue from treatment, they are concentrated among such men. These men, Catalona says, should have their PSA levels checked once or twice a year. If the level is high - above four nanograms per milliliter in the Hybritech test - they should have a rectal exam, an ultrasound exam, and a "quadrant" or "sextant" biopsy, which uses a computerassisted needle probe to image each part of the gland, obtaining samples from suspicious areas. Men should not have a biopsy if they suffer from prostatitis, because the biopsy may induce a dangerous infection. "Take the antibiotic and come back," Catalona says.
If a carcinoma is discovered, the patient should learn its location and size. Is it still confined within the prostate, or has it spread to the capsule? In the former case the disease is unlikely to have metastasized, and hence may be a candidate for surgery. In the latter case there is some chance that metastasis has already occurred and that it is too late for prostatectomy to do any good. Size is an important proxy measure of the likelihood that the carcinoma has passed through the genetic steps necessary to become dangerous: a widely but not universally accepted standard is that tumors less than half a cubic centimeter in volume are probably not old enough to have acquired the ability to grow rapidly and spread. Because tumor size is hard to determine precisely with a biopsy, surgeons also give considerable weight to the degree of differentiation, which describes, so to speak, the "cancerlike" qualities of the carcinoma. "Welldifferentiated" carcinomas are, despite the name, similar to the tissue surrounding them, and relatively unlikely to metastasize; "poorly differentiated" carcinomas are more likely to be advanced. All these factors play a role in determining the degree of threat. In general, surgeons consider poorly differentiated tumors that are still contained within the prostate to be the best candidates for immediate surgery.
Before submitting to a prostatectomy, Catalona says, men should choose their surgeon carefully. Ask surgeons if they know the nervesparing technique, how many prostatectomies they have performed, and at what rate their patients have experienced side effects. Avoid doctors who do not know the technique, who have performed fewer than 150 prostatectomies, or who have patients with higher rates of incontinence and impotence than those reported in journal articles by surgeons from major teaching hospitals. "If your surgeon can't tell you those rates," Catalona says, "that's grounds to think about trying another one."
Although such precautions will surely minimize the chance of an undesirable outcome on the individual level, they do nothing for the likelihood of an undesirable outcome on the collective level - that is, the possibility that the nation's healthcare spending will rise by billions to cover the cost of thousands of unnecessary operations. Indeed, as Kit Simpson says, "Surgery is expensive, justified or unjustified. The only truly cheap method of dealing with prostate cancer would be to prevent it."
Happily, prevention is what the National Cancer Institute is now examining. A number of laboratory reports suggest that prostate cancer is somehow linked to 5alphareductase, the enzyme that converts testosterone to dihydrotestosterone, the hormone that induces prostate swelling. The relation between the enzyme and the genetics of cancer is unknown, but it is known that finasteride (Proscar) stops the enzyme from functioning. Last month the NCI was scheduled to begin a clinical trial to examine whether finasteride can prevent cancer. The nationwide trial, which is headquartered in San Antonio, will randomly divide 18,000 healthy men into two groups. Half will take finastende for seven years; half will take a placebo. "It's a massive effort," says Brent Blumenstein, who assisted in designing the trial. "Whether this is the answer should come clear."
Blumenstein, like every statistician I have spoken with, is deeply skeptical of a national screening program. At fortynine he is rapidly approaching the age group most likely to be screened. What would he do, I asked, if he learned that he had a relatively large carcinoma in the center of his prostate? His answer came quickly. "Personally," he said, "I would start talking to the best surgeon I could find."