Breast Cancer Screening: Five Takeaways from New Systematic Review of Global Guidelines

In a recently published systematic review of guidelines for breast cancer screening, researchers assessed 23 guidelines from 11 countries or regions that were published between 2010 to 2021. In what may be the largest review to date to examine international breast screening guidelines, the authors noted common similarities as well as differences regarding recommendations for screening age, intervals and methods for women who have average or high risk for breast cancer.

Here are some takeaways from the research.

1. When should breast cancer screening stop? Three guidelines, including those from the American College of Radiology (ACR) and the Society of Breast Imaging (SBI), emphasized that this decision is subject to health status, noting that breast cancer screening could cease for those with lower than five to 10 years of remaining life expectancy. Other guidelines, including guidelines from the American College of Physicians, said screening can stop after the age of 75 unless projected life expectancy was greater than seven to 10 years. Guidelines from Germany and Singapore suggested an age limit of 70. There was no age limit noted for breast cancer screening in nine of the reviewed guidelines.

2. When it comes to women with dense breasts, the ACR recommended annual magnetic resonance imaging (MRI) screening. Adjunctive use of ultrasound in addition to mammogram is recommended for screening of asymptomatic women with dense breasts, according to Brazilian guidelines as well as those from SBI/ACR. Annual mammography and ultrasound screening are recommended by the National Cancer Center of China for those with dense breasts.

(Editor's note: For related articles, see "Large Study Finds Elevated 10-Year Breast Cancer Risks in Women with Dense Breasts and Benign Breast Disease" and "Ten Key Considerations with Breast MRI.")

3. For women with genetic susceptibility to breast cancer, guidelines from the SBI/ACR and the Ministry of Health in Singapore recommended annual screening with mammograms or MRI beginning at ages 25-30. For women who have breast cancer susceptibility gene 2 (BRCA2), the European Society of Breast Cancer Specialists (EUSOMA) recommended the start of annual MRI screening between the ages of 25 to 29. For women who have the TP53 gene, EUSOMA encouraged initial screening to begin at the age of 20. When it comes to patients with genetic predisposition who cannot tolerate MRI, the ACR recommended ultrasound as an adjunct to mammograms or digital breast tomosynthesis (DBT).

4. The authors of the systematic review noted that a number of randomized controlled trials from Canada, Sweden, the United Kingdom and other countries revealed higher false positive biopsy results and overdiagnosis with screening in patients aged 40 to 44. However, the majority of guidelines recommended that women at average risk of breast cancer begin mammographic screening at the age of 40.

5. Multiple guidelines recommended annual mammograms or MRI screening for patients diagnosed with invasive breast cancer, ovarian cancer, lobular carcinoma in situ (LCIS), ductal carcinoma in situ (DCIS) or atypical ductal hyperplasia (ADH).