What are the guidelines for breast cancer screening using Mammography (mammography)?

From the Guidelines

Breast cancer screening guidelines recommend biennial mammograms for women aged 50-74 years, with the decision to start screening between ages 40-49 being an individual one, taking into account the benefits and harms of screening. Women at average risk should discuss their screening options with their healthcare provider, considering factors such as family history, genetic mutations, and previous radiation therapy to the chest.

• The American Cancer Society recommends that women at average risk should have the opportunity to begin annual screening between the ages of 40 and 44 years, and women aged 45-54 years should undergo regular screening mammography beginning at age 45 years 1.
• The US Preventive Services Task Force recommends biennial screening mammography for women aged 50-74 years, with a grade B recommendation, and a grade C recommendation for women aged 40-49 years, indicating that the decision to start screening should be an individual one 1.
• The European Guidelines for quality assurance in breast cancer screening and diagnosis recommend mammography screening every 2 years for women aged 50-69 years, with a recommendation to discuss the benefits and risks of screening with the woman who is to be screened 1.
• Women with higher risk factors, such as familial breast cancer or proven BRCA mutations, may benefit from additional screening methods like MRI, and should start screening earlier, typically at age 30, with annual MRI concomitantly or alternating every 6 months with mammography 1.
• Clinical breast exams by healthcare providers are not recommended for breast cancer screening among average-risk women at any age, and breast self-awareness is encouraged for all women to recognize changes in their breasts 1.
• Screening should continue as long as a woman is in good health and expected to live at least 10 more years, with individual screening plans developed with healthcare providers based on personal risk factors and preferences.

From the Research

Breast Cancer Screening Guidelines

• The American College of Radiology (ACR) recommends annual screening beginning at age 40 for women of average risk and earlier and/or more intensive screening for women at higher-than-average risk 2.
• For most women at higher-than-average risk, the supplemental screening method of choice is breast MRI 2.
• Women with genetics-based increased risk, those with a calculated lifetime risk of 20% or more, and those exposed to chest radiation at young ages are recommended to undergo MRI surveillance starting at ages 25 to 30 and annual mammography (with a variable starting age between 25 and 40, depending on the type of risk) 2.
• Mutation carriers can delay mammographic screening until age 40 if annual screening breast MRI is performed as recommended 2.
• Women diagnosed with breast cancer before age 50 or with personal histories of breast cancer and dense breasts should undergo annual supplemental breast MRI 2.
• Others with personal histories, and those with atypia at biopsy, should strongly consider MRI screening, especially if other risk factors are present 2.
• For women with dense breasts who desire supplemental screening, breast MRI is recommended 2.
• For those who qualify for but cannot undergo breast MRI, contrast-enhanced mammography or ultrasound could be considered 2.

Screening Intervals

• The balance between the benefits and harms of different screening intervals is still a matter of debate 3.
• Annual compared to biennial screening may have small additional benefits but an important increase in false positive results 3.
• Triennial compared to biennial screening may have smaller benefits while avoiding some harms 3.
• In women 50-69, biennial screening may be the most favorable option 3.
• In younger women (aged 45-49), annual screening may have a less favorable balance, while in women aged 70-74 years longer screening intervals may be more favorable 3.

Effectiveness of Screening Methods

• Mammography screening has consistently been shown to significantly reduce breast cancer mortality over a variety of study designs 4.
• MRI has been shown to detect cancers that were not identified on mammography 6 months earlier in women at genetically high risk of developing breast cancer 5, 6.
• Screening MRI in high-risk women was capable of detecting mammographically and clinically occult breast cancer 6.