Screening Tests Give Best Information About Health Risks

When you’ve got your health, the saying goes, you’ve got everything. But for some healthy adults, that’s not enough – they keep wondering if something might be wrong. This might help explain the growing popularity of full-body health scans in the United States. Ads urge people to be scanned for the sake of wellness, for peace of mind, or to reassure their family. But those scans, which typically cost more than $700 (usually not covered by insurance), are generating controversy and concern by many physicians.

“The short answer,” says David A. Severance, MD, Assistant Professor of Family and Community Medicine at the Medical College of Wisconsin, “is that these scans are not recommended. We don’t have any evidence that they provide information that would improve the patient’s quality or quantity of life.”

Severance and other physicians say the scans, which are similar to CT scans, raise anxieties among patients over abnormalities that generally are harmless. Even worse, they may lead to further, more invasive procedures that may otherwise have not have been done. And this can put the patient at risk of complications from the procedure. In Body Scans Not Always Needed in the December 1, 2002 issue of HealthLink, Dr. Rebekah Wang-Cheng warned readers: “The American College of Radiology does not believe there is enough scientific evidence that body scans are cost-effective and prolong life. The American Cancer Society also cautions that there is a need for more data.”

Dr. Severance, whose practice focuses on wellness and prevention, believes healthy adults should have certain screening tests performed that could be early signs of two potentially deadly diseases – cancer and heart disease.

Tests Can Help Detect Cancer in Early Stages
The risk for cancer generally increases with age. Not all cancers can easily be detected early, when treatment is most effective, either by full-body scans or by conventional screening tests, he notes. Cancers that are difficult to detect early are those of the pancreas, liver, lungs and ovaries. These cancers, although relatively rare, are also among the deadliest.

The good news, though, Dr. Severance says, is that many common cancers can be detected early through fairly simple, inexpensive blood tests or physical examination.

Breast cancer: Although this is the cancer women seem to fear the most, only a small percentage of healthy women under 40 develop it. Mammography remains the gold standard for early detection, Dr. Severance says, but he notes that not everyone agrees when or how often women should start having mammograms. Unless a woman has a strong family history of breast cancer, he recommends mammograms every one to three years for women aged 40 to 50, and annually for women 50 and older. And he urges women to do breast self-examinations monthly, because women can detect lumps and other changes that even mammography can miss.

Colon cancer: Dr. Severance tells his patients to begin screening at age 50, unless an immediate family member has a history of cancer or precancerous lesions, in which case screening should start either at age 40, or 10 years earlier than when the relative developed the problem. The National Cancer Institute and American Cancer Society recommend a number of options for screening. Dr. Severance recommends colonoscopy – a procedure insurance routinely pays for – to his patients. If results are normal, the test should be repeated every 10 years. A second option that has very good evidence of effectiveness is fecal occult blood testing. In this simple procedure, a patient collects small samples of stool on special cards, which are then tested for the presence of blood. If blood is detected, the patient is referred for a colonoscopy for more definitive evaluation. If negative, the study should be repeated annually, he says. Other screening options include flexible sigmoidoscopy and air contrast barium enema.

Prostate cancer: The screening test for PSA, or prostate-specific antigen, is widely offered to men for early detection of prostate cancer, but Dr. Severance has some cautions about it. “About 60% to 70% of men over 65 have some form of prostate cancer,” he says, “but only a small percentage of men die of it. To date, the PSA test has not demonstrated an ability to discriminate between the benign and the more deadly types of prostate cancer. Routine use of the PSA test remains a controversial area.” Consequently, he does not routinely suggest his patients be tested for PSA. Instead he recommends that, starting at age 40, they undergo a simple digital rectal examination by their doctor every one to three years depending on their age. He does recommend a PSA test if the man’s father or a brother has a history of prostate cancer, if they experience urinary symptoms indicating an enlarged prostate, or if their digital rectal exam was abnormal.

“In addition,” Dr. Severance says, “there’s an art to interpreting the results of the test.” Typically, a PSA test rating of less than 4 has been considered within the normal range. However, he believes that readings in a borderline range (3.5 – 4.5) or a significant change in the reading from year to year may need to be interpreted differently based upon the age of the patient and other factors. If a patient or his physician desires a PSA test, Dr. Severance recommends discussing in detail how the results will be interpreted and followed over the long term.

Skin cancer: It’s the most common cancer in the United States, affecting 1 in 7, and its incidence is growing rapidly. Although it’s rarely fatal, almost 9,800 Americans will die of skin cancer this year, and 7,400 of those deaths will be from melanoma – nearly always due to sun exposure. Skin cancer is detected through visual examination, and Dr. Severance tells his patients to examine their skin (or have someone do it) every few months for changes such as any growth, mole or discoloration that appears suddenly or begins to change, or for a sore that doesn't heal.

Testicular cancer: This rare type of cancer usually affects younger men between 18 and 40. Dr. Severance urges his younger male patients to do monthly self-exams to feel for any lumps, bumps or changes.

Cervical cancer: Pap smears done during a pelvic exam are highly effective in detecting cervical cancer, which is one of the most treatable and curable of all cancers when detected early. Dr. Severance recommends that women have their first Pap test by age 18 – or earlier if they are sexually active. Thereafter, he recommends it be done every 1 to 3 years through age 65. Exception: For women who have had a hysterectomy for fibroid tumors or other benign condition, Dr. Severance recommends they have a Pap test after the surgery. If that test is normal, it need not be repeated for 10 years. If the hysterectomy was done as treatment for cervical cancer, then it needs to be repeated more frequently and should be discussed with the patient’s gynecologist.

Lifestyle Choices Can Prevent No. 1 Killer of Men and Women
Although both men and women fear the prospect of having cancer, the greatest health risk for both is actually heart disease. Heart disease kills more American men and women every year than all forms of cancer.

“Preventing heart disease is very much a lifestyle issue,” Dr. Severance says. With all my patients, we discuss six key risk factors that strongly influence whether they will develop cardiovascular problems.”

• Family history of heart disease
• Age and gender. The risk for cardiovascular disease increases in men over 45, and in women after menopause
• Smoking. Not only does it increase risks for heart disease, it strongly influences certain cancers – lung, bladder, and mouth and throat, among others.
• Hypertension (high blood pressure)
• High cholesterol
• Obesity

• Blood pressure checked annually
• Cholesterol tested through a blood test beginning at 35; if normal, repeat in five years
• Diabetes screening with a fasting blood test

For all his patients, particularly those who are overweight, he recommends maintaining an active lifestyle through regular exercise and eating a “reasonable” diet, which he describes as one that is:

• Low in saturated fats (animal fats and other fats that are solid at room temperature)
• Higher in fiber. He tells patients to increase dietary fiber by eating more whole-grain breads and cereals, and more fresh fruits and vegetables daily
• Moderate in alcohol – one drink a day for women, two for men. A standard drink means 12 ounces of beer, 6 ounces of wine or 1½ ounces of 80 proof grain alcohol

Other preventive steps healthy adults can take are getting annual flu shots, and for those over 65, a one-time vaccination against pneumonia. Postmenopausal women should have their bone-mineral density measured at least once to determine if they are at risk for osteoporosis.

Annual physicals for healthy adults? Dr. Severance recommends them. “See your doctor every year so you can update each other. Your physician can update you about medical breakthroughs, and you can update your physician about changes affecting your life.”

Meanwhile, arguments against full-body scans continue to grow. At the annual meeting of the Radiological Society of North America in early December, findings from a study of 1,192 patients ages 22 to 85 who had full-body scans at private, for-profit imaging centers were presented. Conclusion: No one under 45 had scan results that strongly suggested cancer, and patients younger than 40 had very few findings requiring further tests. Other research has shown that follow-up tests usually determine that scan-detected abnormalities are insignificant.

Barbara Abel
HealthLink Contributing Writer

MCW Health News presents up-to-date information on patient care and medical research by the physicians of the Medical College of Wisconsin.