Physician discusses benefits, dangers of cancer screening
12/08/2012 4:42 PM
12/08/2012 4:42 PM
First do no harm – that’s the main guideline physician Michael LeFevre uses in deciding whether people who have no symptoms should be screened for cancer.
Because harm can and does occur to otherwise healthy people from screening, LeFevre told a symposium of family-medicine doctors Saturday at the Wichita Marriott. The fact becomes even more important as patients believe the screenings are more of a safeguard than they are.
LeFevre said one erroneous belief among some women that must be overcome is: If I don’t get a mammogram I will die of breast cancer. If I do get a mammogram every year from age 40 until I die, I cannot die of breast cancer.
The University of Kansas Medical Center and School of Medicine sponsors the annual symposium to help doctors refine their diagnostic and therapeutic skills. LeFevre reviewed current recommendations about screening for breast and prostate cancers for the physicians – and then told them how he advises his patients.
LeFevre, a professor and director of clinical services at the University of Missouri School of Medicine in Columbia as well as a full-time physician, came with extra clout to talk about the screenings: He is on the U.S. Preventive Services Task Force. This independent panel of experts in 2009 recommended that women ages 50 to 74 cut back having mammograms to every other year, and that women in their 40s be judged individually as to whether they should receive the screening, taking into account their own judgment of the benefits and harms of mammograms.
The task force also recommends against prostate-specific antigen-based screening for prostate cancer.
Among the ways mammography harms, LeFevre said: “Radiation is not harmless.” A mammogram can be painful. And there is anxiety from the false positives that the screening can produce – which happens half the time in women in their 40s who are screened annually, he said. Such women should be told to expect such callbacks, LeFevre told the physicians.
For women over 40 who have not been screened for breast cancer, 3 percent will die of it, LeFevre said. Women who begin to be screened at age 50 will see that risk lowered to 2.3 percent, while women who start receiving the screening at age 40 see the risk lowered only very slightly – to 2.2 percent.
The risk of breast cancer increases for women in their 60s and 70s, he said.
What he does in his own practice, LeFevre said:• Discusses getting a mammogram with patients at age 40, speaking neither for nor against it.
• Encourages it every other year for women starting at age 50.
• Strongly encourages it every other year for women starting at age 60.
• Doesn’t discourage it for women starting at age 75 if they’re in good health.
• Sees declining returns from mammography at age 85.
He hasn’t taught women how to do self breast exams for 30 years, he said, instead advising “self-awareness. … If something changes, see me.”
One physician in the audience told LeFevre that women drive to Wichita from out of town to undergo thermography to try to detect breast cancer, believing that it is safer than mammography. LeFevre said there was no data with which to judge thermography or other forms of imaging, so doctors should recommend what they know does help: mammography.
“The appropriate use of mammography will prevent some deaths from breast cancer,” he said.
When it comes to prostate-specific antigen (PSA) blood testing for prostate cancer, LeFevre said, people may say: It’s just a blood test – why not screen? But the benefits are uncertain, he said. And as far as the negatives: Eighty percent of results are false positives. When biopsies are then ordered on those bad results, a third of the patients have moderate or major problems from the biopsies, and 1 percent of them are hospitalized because of effects from the biopsy.
Meanwhile, nine out of 10 men who have clinically localized prostate cancer will be fine 10 years later without a prostatectomy, he said, while one in 200 men who receive a prostatectomy will die from it.
“We are schooled to believe that cancer is a death sentence,” when it’s not, LeFevre said.
“We kill people by screening for prostate cancer,” LeFevre said. “We need to acknowledge that.”
He said that PSA screening should not be done without a person’s consent or knowledge and that it is wrong to say that black men will benefit from screening, though they should be made aware that they face a higher chance of developing prostate cancer than men of other races do.
LeFevre says that when advising men about prostate screening, he asks them which camp they’re in: They feel well and they want to go the route of doing more good than harm, or they worry about cancer and understand there are risks to testing.
The task force is studying lung cancer screening now, he said.