The Good and the Bad of Cancer Screening
01 Jun 2003
“Why did my wife die of breast cancer when she’s had a mammogram every year?” Or “I went through hell after the mammogram revealed a possible cancer.” Or “During a routine checkup examination the doctor discovered my 73 year old husband had an elevated PSA test. He didn’t have any symptoms, but a biopsy revealed cancer of the prostate. A specialist advised a radical prostatectomy. Now he’s impotent and in diapers.” Every year I receive letters asking these questions. That’s why it’s vital to know the negatives as well as the positives about cancer screening.
There is no doubt that cancer screening saves lives. But there is also a price to pay. Any woman who agrees to mammography has to understand the possibility of a frightening telephone call that a second mammogram is needed. Why? Because a suspicious area has been spotted that requires additional inspection. At this point it takes a strong woman not succumb to the conclusion that, “I’ve got breast cancer.” And sleepless nights begin.
Unfortunately the solution can’t be found overnight as it takes time to arrange for another mammogram. Then the next call may be, “We’re still not sure and we need to do a needle biopsy of the breast.” So another wait for the biopsy and more days for the result. Then even if the news is good, patients are often left with the suspicion that just maybe, just maybe, a cancer has been missed. And if a woman has 30 or more mammograms during her lifetime, there’s a good chance that sooner or later this scenario will happen.
But even if cancer is diagnosed by mammography, how many lives does it save? There is no simple answer as major health organizations can’t agree. For instance, a Danish study concluded that mammography simply does not save lives and the National Cancer Institute agreed. Others claim mammography reduces the risk of death from 30 to 50 percent. Not encouraging figures.
Faced with a procedure that may needlessly cause sleepless nights, or fails to diagnose cancers that are present, some women refuse this test. Besides, there is a extremely small possibility that the radiation from 30 or more mammograms during a lifetime may cause breast cancer.
The negative effect of mammography is that it is not sensitive enough to diagnose early cancer. Rather, it’s a “lump diagnosis” and lumps don’t form overnight. By the time the cancer is large enough to be detected it has often spread to other organs. This is why the aforementioned man’s wife died of breast cancer.
But why did Mr. X end up impotent? It’s because technology today often takes the place of common sense. At age 73 the PSA test is very questionable. Studies show that developing prostate cancer is much like getting gray hair. By age 70 about 40 percent of men have microscopic areas of cancer in the prostate gland.
Moreover, even if this man was destined to eventually die from this malignancy it would not end his life for 15 years. During that time there’s a good chance he may die of some other disease. It’s been aptly said that, “Getting older is invariably fatal, cancer of the prostate only sometimes.” It could be argued that the doctor should never have ordered a PSA test. By doing so he triggered a chain-reaction that ruined this man’s quality of life.
Medical consumers should also be aware that surgical complications tend to be under-reported. In effect, the patient who wets his pants is much more aware of it than the surgeon who performed the operation.
The cold facts show that only two screening tests are universally agreed to save lives. The Pap test for cervical cancer and colonoscopy to detect pre-cancerous polyps of the large bowel.
From past experience I’m acutely aware that to criticize mammography even mildly is like damning motherhood. Radiologists and organizations with vested economic interests in this procedure invariably accuse me of presenting false facts and putting women’s lives at risk. I expect this will happen again.
But I’m not against mammography and I always discuss the pros and cons of this test with patients. They can then make the final decision themselves, confidently, after being informed of both sides of the coin.
