The US Preventive Services Task Force (USPSTF) recently issued draft recommendations on breast cancer screening that lower the starting age for routine mammography screening for those at average risk.1 The proposed recommendations are an update to USPSTF’s 2016 guidance on this topic.
What’s different. There are 2 major differences in the new recommendations:
- Recommendation for routine mammography starting at age 40 for women at average risk for breast cancer (eg, no personal or family history or genetic risk factors). This is a “B” recommendation (offer or provide the service). Previously, the recommended age to start routine mammography was 50 years, with a “C” recommendation (individual decision-making) for those ages 40 to 49 years.
- No mention of digital tomosynthesis. Previously, this screening modality was rated as an “I” (insufficient evidence to assess). While the new draft recommendation does not mention tomosynthesis, the related evidence report concludes that there is still insufficient evidence to assess it.2
What’s the same. Several important recommendations have not changed. The USPSTF continues to state that the evidence is insufficient to assess the value of (1) supplemental screening with breast ultrasonography and magnetic resonance imaging in women with dense breasts and negative mammograms and (2) mammography in women ages 75 years and older.
And, most importantly, the USPSTF continues to recommend biennial, rather than annual, mammography screening. This recommendation is based on studies that show very little difference in outcomes between these strategies but higher rates of false-positive tests and subsequent biopsies with annual testing.2
What others say. USPSTF’s draft recommendations continue to differ from those of the American Cancer Society, which for average-risk women recommend individual decision-making from ages 40 to 45 years; routine annual mammography for those ages 45 to 54 years; annual or biennial mammography for those ages 55 years and older; and continued screening for women older than 75 years who are in good health and have a life expectancy ≥ 10 years.3
The USPSTF’s rationale for lowering the age at which to start routine mammography is a little puzzling. Several conclusions in the draft evidence report seem to contradict this recommendation:
In the summary of screening effectiveness, the report states “For women ages 39 to 49 years, the combined [relative risk] for breast cancer mortality was 0.92 (95% CI, 0.75 to 1.02; 9 trials); absolute breast cancer mortality reduction was 2.9 (95% CI, –0.6 to 8.9) deaths prevented per 10,000 women over 10 years. None of the trials indicated statistically significantly reduced breast cancer mortality with screening….”2
And in a summary of screening harms, it states that for “every case of invasive breast cancer detected by mammography screening in women age[s] 40 to 49 years, 464 women had screening mammography, 58 were recommended for additional diagnostic imaging, and 10 were recommended for biopsies.”2
The USPSTF apparently based its decision on a modeling study conducted by the Cancer Intervention and Surveillance Modeling Network (CISNET) at USPSTF’s request. This analysis found that screening biennially from ages 50 to 74 years resulted in about 7 breast cancer deaths averted over the lifetimes of 1000 females and that 1 additional death was averted if the starting age for screening was 40 years.4
Financial implications. The USPSTF’s change from a “C” to a “B” recommendation for women ages 40 to 49 years has financial implications. The Affordable Care Act mandates that all “A” and “B” recommendations by the USPSTF have to be provided by commercial health plans with no out-of-pocket costs. (This is currently being challenged in the courts.) However, any follow-up testing for abnormal results is not subject to this provision—so false-positive work-ups and biopsies may result in out-of-pocket costs.
What to discuss with your patients. For women ages 40 to 50 years, discuss the differences in mammography recommendations and the potential risks and benefits of the procedure, as well as financial implications; respect the patient’s decision.
For those ages 50 to 74 years, recommend biennial mammography.
For those older than 74 years, assess life expectancy and other health problems. Discuss the potential risks and benefits of the procedure and respect the patient’s decision.
For all patients, document all discussions and decisions.