The American College of Physicians (ACP) now urges biennial mammography for women aged 50 to 74 at average risk. The recommendation is among the most consequential ACP breast cancer screening guideline updates of 2026.

The new ACP breast cancer screening guidelines were released at the 2026 Internal Medicine Meeting and published in the Annals of Internal Medicine. They tighten the rules on when to start screening, when to stop, and which imaging tools to use.

What the new guidance says

For asymptomatic, average-risk women aged 50 to 74, the group recommends mammography every 2 years. It defines "average risk" as women without a personal or family history of breast cancer. They also have no known high-risk gene variants such as BRCA1 or BRCA2, and no prior high-dose chest radiation at a young age.

For women aged 40 to 49, screening should be a shared decision between the patient and the clinician. For women 75 and older, or those with a limited life expectancy, clinicians should weigh whether to stop. For women with dense breasts, 3D mammography may be considered. Extra imaging is not routinely advised in average-risk patients.

Why the new ACP breast cancer screening guidelines pick biennial

Amir Qaseem, MD, PhD, MHA, MGIN, FRCP, FACP, is the first author of the new guidelines. He is also Senior Vice President of Clinical Policy and the Centre for Evidence Reviews at the American College of Physicians (ACP).

He told : "Annual screening resulted in more false-positive recalls and biopsies than biennial screening. Annual screening creates additional patient burden and costs, and current evidence does not show added benefit of annual screening over biennial screening."

"Therefore, the ACP says clinicians should initiate biennial mammography in asymptomatic, average-risk females aged 50 to 74 years," Qaseem added.

Why are ages 40 to 49 treated differently

For this age group, Qaseem said the choice should be personal.

"For asymptomatic, average-risk females aged 40 to 49 years, clinicians should use shared decision making. It's a personal choice. Clinicians should discuss the individual patient's risk for breast cancer, her values and preferences, and uncertainty around the benefits and harms of screening for breast cancer," he told .

"There is a small absolute reduction in mortality (only in ages 45 to 49 years) but no difference in advanced breast cancers, which needs to be balanced against harms," he said.

He listed the harms. They include overdiagnosis, overtreatment, false-negative findings, more follow-up tests, false-positive distress, added radiation exposure, and lower future screening adherence.

What it means for women aged 75 and older

For older women, the ACP breast cancer screening guidelines back a candid talk about stopping.

"Clinicians should discuss discontinuation of breast cancer screening based on shared decision making in asymptomatic average risk females aged 75 years or older or with a limited life expectancy," Qaseem said.

"Continuing screening beyond the age of 74 showed no difference in breast cancer mortality but resulted in additional testing with or without biopsy and overdiagnoses," he added.

Dense breasts and 3D mammography

For women with BI-RADS category C or D breast density, the ACP breast cancer screening guidelines allow supplemental digital breast tomosynthesis (DBT). DBT is a 3D mammography method that can outperform standard tools in dense tissue.

"Clinicians should consider using supplemental DBT in females with breast density of BI-RADS category C or D based on benefits, harms, additional radiation exposure, availability, values and preferences, and costs. However, do not use supplemental MRI or ultrasound in females with breast density of BI RADS C or D," Qaseem told .

A divided expert response

Not everyone agrees with the new ACP breast cancer screening guidelines. Some experts warn that the policy relies on outdated data and may increase mortality.

Debra Patt, MD, PhD, MBA, is Executive Vice President of Public Policy and Strategy for Texas Oncology. She told her concerns.

"We are concerned that the ACP guidelines will lead to delayed diagnoses, particularly among young women 40 to 49 and women with dense breasts. The American College of Radiology and the Society for Breast Imaging have both voiced concerns about the diminished screening recommendations," she said.

"To be clear, annual mammography in women 40 to 49 who are average risk leads to earlier diagnosis and saves lives. In contrast, for women over 50 of average risk with average breast density can safely screen with biennial mammography," Patt said.

She likened cancer screening to other forms of routine self-care. She also said women with dense breasts can benefit from a stronger screening plan, and that family history can warrant a more rigorous approach.

How big is the breast cancer problem

Breast cancer makes up about 30% of new female cancer cases in the U.S. each year. A woman in the U.S. has roughly a 1-in-8 lifetime risk of the disease. Most cases occur in women 50 or older. The median age at diagnosis is 62. A diagnosis under age 45 is rare.

"Cancer screening saves lives," Patt told. "Every time there is an article to heighten awareness of breast cancer screening, women are reminded of the importance of screening, they get screened, they are diagnosed earlier, and their lives are saved."

The new ACP breast cancer screening guidelines now feed a wider debate. The question is how to balance early detection against the real harms of over-testing. The new ACP breast cancer screening guidelines also raise the stakes for clinics planning patient outreach. Coverage on Medigear.uk explains why hospital teams, distributors, and clinic operators must follow the evolution of this guidance.

Source: Medical News Today — based on ACP guidance presented at the 2026 Internal Medicine Meeting and published in the Annals of Internal Medicine.