In an effort to reduce confusion and improve the benefits of screening for cancer, the American College of Physicians (ACP) recently issued guidelines for testing people who show no signs or symptoms or who are at average risk for five major types of cancer—breast, ovarian, prostate, cervical, and colorectal. The guidelines were published in the Annals of Internal Medicine along with a companion article outlining a framework to help physicians think and talk with their patients about the risks, benefits, and value of cancer screening.
For its new report, the ACP reviewed clinical guidelines and evidence from the U.S. Preventive Services Task Force, the American Academy of Family Physicians, the American Cancer Society, the American College of Obstetrics and Gynecology, the American Gastroenterological Association, the American Urological Association, and the ACP. The organizations may differ in their opinions on types and frequency of testing for cancer, which can lead to confusion for consumers and their healthcare providers.
The committee, called the High Value Care Task Force, defines "high value care" as the delivery of services providing benefits that make their harms and costs worthwhile. The ACP in its report says it wants health practitioners to focus on tests that improve health, avoid harms, and eliminate wasteful practices.
Both too much and too little cancer screening is of concern to health experts. Screening is encouraged for certain groups because it can provide the benefit of catching cancer early, when it is most treatable and before it has spread. But testing too frequently or in people with low risk of cancer can increase the possibility of causing harm.
Some of the harms from screening can come from false positives, test results that indicate disease when none is present. This can lead to worry and unnecessary follow-up tests and procedures. Over-testing might also lead to needless treatment. For instance, prostate cancer screening with a PSA test can detect some tumors that might never cause a threat to health or life expectancy. This is why the ACP says it is trying to strike a balance between enough but not too much screening.
"ACP wants smarter screening by informing people about the benefits and harms of screening and encouraging them to get screened at the right time, at the right interval, with the right test," said Wayne J. Riley, MD, ACP president. "Many people have a lack of understanding about the trade-offs of screening. Study after study has consistently shown that patients and many physicians overestimate the benefits and are unaware of and/or downplay the potential harms of cancer screening," Riley added.
The ACP report largely agrees with other expert guidelines released in the last few years for the five types of cancer. The following are among the key considerations for people with average risk:
- Women aged 40 to 49 years: discuss the benefits and harms of screening mammography with a health practitioner; if the choice is to undergo screening, have it done every two years.
- Women aged 50 to 74: have screening every two years; however, some professional organizations recommend these women have mammograms annually (for a summary, see Breast Cancer Screening for Adults 50 and Up).
- Don't have imaging tests other than mammography, such as an MRI, for breast cancer screening.
- Average-risk women under the age of 40 years or over the age of 75 should not be screened for breast cancer.
- Women at average risk should begin screening at age 21 years using Pap tests without HPV tests every 3 years.
- Every 3 years for women aged 30 years or older, or for those who prefer screening less often than every 3 years, have a combination of Pap and HPV testing once every 5 years. However, recent interim guidelines from a panel of experts representing several major health organizations say that HPV testing may be offered as a screening option without a Pap test for women aged 25 and older. (For more on this, read Experts Offer Advice on hrHPV Testing as a Primary Screen for Cervical Cancer.)
- There is no need for HPV testing in women younger than 30 years. HPV infections are common in this age group and often resolve without treatment.
- Women and men aged 50 to 75 years should choose one of the following screening methods:
- Don't screen for colorectal cancer more frequently than these recommendations, in those younger than 50 years, or those over 75 years.
- Don't undergo screening—no appropriate test is currently available.
- Men aged 50 to 69 years who are thinking about having a PSA test: talk to a health practitioner about the limited potential benefits and substantial harms of screening for prostate cancer solely depending on the PSA test. The test has a high rate of false positives, which in the past has resulted in many surgeries that may not have been warranted and caused side effects in many men, including sexual dysfunction and incontinence.
- Don't undergo screening for prostate cancer using the PSA test without an informed discussion and a clear preference for screening.
- Screening for prostate cancer using the PSA test is not advised for men younger than 50 years or older than 69 years or those with a life expectancy of less than 10 years.
- PSA screening in conjunction with a digital rectal examination may be of greater benefit.
Introductions of new cancer screening tests and reevaluations of existing ones can be confusing for consumers. Lab Tests Online publishes a summary of screening tests that puts cancer screening and the risks and benefits into context. As significant changes to guidelines are announced, Lab Tests Online will report on them, keeping readers up to date.