The goal of screening and early detection programs is to find and treat diseases before they cause irreversible damage to our bodies. That is the ultimate goal of early detection programs but, unfortunately, medical science is not there yet.
In fact, some screening tests can cause almost as much harm as good. False positive results lead to more invasive tests and over-treatment of minor findings that would never progress to become clinically significant. False positives also cause anxiety — to patients and health care providers.
While false positive test results can't be completely avoided, their downside can be decreased when the types, timing and subjects of screening tests are carefully chosen.
Screening should not be unnecessarily applied to low risk populations.
It's important to weigh the risks, benefits, and alternatives. Tests can be chosen, timed and targeted to those people most likely to benefit from the results. Screening should not be unnecessarily applied to low risk populations.
The American College of Physicians has just published recommendations for cancer screening geared toward achieving that balance. The group looked at five common types of cancer screening — breast, cervical, ovarian, prostate and colorectal cancers.
Women over 30 should continue routine screening either with a Pap smear every three years or a Pap smear plus HPV testing every five years.
Women 65 years old and over may discontinue routine screening if they have had three consecutive every-three-year Pap tests or two consecutive every-five-year Pap smear plus HPV tests.
The group looked at five common types of cancer screening — breast, cervical, ovarian, prostate and colorectal cancers.
Those women who have had a hysterectomy with removal of the cervix do not need cervical cancer screening for the rest of their lives.
Everyone between ages 50 and 75 should be screened for colorectal cancer with one of the following four strategies:
- An annual high sensitivity fecal occult blood test (FOBT) or fecal immunochemical test (FIT) OR
- Sigmoidoscopy every five years OR
- FOBT/FIT every three years, along with sigmoidoscopy every five years OR
- A colonoscopy every 10 years.
If a person is having colonoscopy every 10 years (or more frequently because polyps have been found in an earlier colonoscopy), the three other screening tests should not be done.
Women of average risk for ovarian cancer should not be screened for ovarian cancer. This includes pelvic examinations, Cancer Antigen125 tests (CA 125) and trans-vaginal ultrasound. The American College of Physicians advises that these screenings offer no benefits for women who have no major risk factors and increases costs and harm to this group, including complications of invasive work-ups.
Complications from prostate biopsy, overdiagnosis, and over-treatment have brought about a big increase in cost and harm.
The ACP advises average risk men, ages 50 to 69, have a one-time discussion about the limited potential benefits and the high potential harms of PSA (prostate-specific antigen) screening blood tests with their doctors. Clinicians should not use this test unless, after discussion, their patient expresses a clear preference for screening.
The ACP recommends that doctors discuss the risks and benefits of mammography and order biennial mammography for women ages 40-49 if an informed woman requests it.
Women aged 50 to 74 should have a mammogram every two years, according to the ACP's recommendations.
Women of average risk should not be screened with MRI or high resolution digital tomosythesis.
Generally, screening for any cancers is not recommended for someone who is of average risk, or if other health problems mean that he or she has less than 10 years to live.
Over-screening is common in our current medical climate. For example, from 23 to 35% of women ages 30-39 had mammography that was suggested by their physicians even though they were actually too young to require such tests.
The elderly are over-screened, too — 38% of women over 80 years old were screened for cervical cancer and 50% for breast cancer.
If your doctor gives you a prescription for a common screening test, discuss the screening recommendation.
Forty percent of gynecologists report routine annual screening for ovarian cancer. Sixty percent of adults had colonoscopies more frequently than guidelines recommend.
The American College of Physicians hopes the guidelines will be used to control costs and the risks to patients. They also hope the guidelines will educate health care providers to consider value when they recommend screening. The ACP urges patients to weigh risks and benefits, and avoid using screening as a way of seeking false peace of mind.
They further recommend keeping overly-invasive follow-up of positive screening results to a minimum. If at all possible, it is better is to watch, wait and re-test, rather than choose a biopsy or other surgical test.
If your doctor gives you a prescription for a common screening test, discuss the screening recommendation with your physician. Find out why the test is being prescribed, what the possible complications might be and whether you are considered at high or low risk. The choice is yours, and you need to be fully informed.
“Screening for Cancer: Advice for High-Value Care From the American College of Physicians,” is published in Annals of Internal Medicine. The article is available for free to the public.