At what age should a female patient with a history of breast cancer screening and significant smoking history stop routine mammography screening, considering average risk and no prior breast cancer diagnosis?

When to Stop Mammography Screening

For average-risk women, discontinue screening mammography at age 75 or when life expectancy falls below 10 years, whichever comes first. 1, 2

Age-Based Stopping Criteria

Age alone should not determine when to stop screening—the decision must incorporate health status, comorbidities, and estimated longevity. 1 The American College of Physicians explicitly states that beyond age 75, decisions should be based on shared decision-making informed by the woman's health status and life expectancy, not age as an isolated factor. 1, 2

Life Expectancy Thresholds

• Stop screening when life expectancy is less than 10 years, as it takes approximately 10 years before screening-detected breast cancer affects survival. 1, 3, 4
• For women aged 70 with no comorbidities, average life expectancy is 19 years; with serious comorbidities, it drops to approximately 11 years. 1
• For women aged 75 with no comorbidities, average life expectancy is 15 years; with serious comorbidities, it falls to approximately 9 years. 1

Screening Benefits vs. Harms After Age 75

Potential Benefits

• Continuing biennial screening from age 70-79 prevents approximately 2 breast cancer deaths per 1,000 women screened. 3, 4
• One additional screen at age 75 results in 1-2 fewer breast cancer deaths per 1,000 women without comorbidities. 5
• More than one-third of all breast cancer deaths occur in women diagnosed after age 70. 2

Potential Harms (Increasingly Problematic with Age)

• False-positive results occur in approximately 200 per 1,000 women screened over 10 years (12-27% of screened women). 3, 4
• Overdiagnosis affects 10-30% of screen-detected cancers in women aged 75+, meaning these cancers would never have become clinically apparent during the woman's lifetime. 5, 3, 4
• Five additional screens over 10 years in women aged 75+ lead to 238-268 false positives per 1,000 women. 5
• Treatment risks increase with age, yet nearly all older women undergo treatment for screen-detected cancers, including overdiagnosed ones. 4

Practical Implementation Algorithm

Step 1: Assess Life Expectancy at Age 75

• Use validated mortality indices incorporating age, comorbidities, and functional status (e.g., Charlson Comorbidity Index). 1, 2
• Consider specific comorbidities: chronic obstructive pulmonary disease, heart failure, end-stage liver disease, end-stage renal failure, or dementia significantly reduce life expectancy. 1

Step 2: Apply Decision Framework

• If life expectancy < 10 years: Discontinue screening—harms outweigh benefits. 1, 2
• If life expectancy ≥ 10 years AND overall health is good: Continue biennial screening based on patient preference after discussing benefits and harms. 1, 2
• If significant comorbidities present at age 75: Strongly consider stopping, as competing mortality risks exceed potential breast cancer mortality reduction. 1

Guideline Variations

The American Cancer Society recommends continuing screening as long as overall health is good and life expectancy exceeds 10 years, with no specified upper age limit. 1, 2 The American College of Radiology similarly recommends no upper age limit. 1, 2 However, the USPSTF concludes there is insufficient evidence to assess screening benefits and harms in women 75 years or older. 2

Critical Pitfalls to Avoid

• Do not use age 75 as an automatic cutoff—individualized assessment of health status and life expectancy is essential. 1, 2
• Do not continue screening in women with severe comorbidities or limited life expectancy—the harms of false positives, overdiagnosis, and unnecessary procedures outweigh mortality benefits. 1, 2
• Do not ignore the patient's smoking history when estimating life expectancy—significant smoking increases competing mortality risks and may shift the benefit-harm balance toward stopping screening earlier. 1