At age 82, Helen was healthy and active and living independently. A mother, grandmother, and great-grandmother, she enjoyed aerobics, tai chi, and walking, painting (which she also taught), writing poetry, and stimulating conversation. She took pride in looking much younger than her age and watched out for her older neighbors.
An active participant in her health care, Helen had been happy when, at 75, she was told by her primary care provider that she no longer needed regular mammograms. But one morning, seven years later, she felt a sharp pain in her right breast. Self-examination revealed a grape-sized lesion under her nipple. Helen sought immediate health care and was diagnosed with a stage IIb tumor.
Given an option of lumpectomy followed by radiation, Helen decided that a double mastectomy would better allow her to return to the life she had been living. After her surgery, however, Helen experienced a steady decline, with increasing pain, debilitating skin lesions, fractures, and edema. Against her will, she was moved to an assisted living facility, where she was too debilitated to participate in activities. Helen died six months later—three years after she discovered her breast lump.
The lack of clear breast cancer screening guidelines has left many providers confused about how to advise their patients, particularly women older than 75. Screening recommendations based on patient age alone are of insufficient value, as health status and life expectancy—which vary widely in this patient population—are also, along with patient preferences, important considerations. The purpose of this article is to present the reported benefits and risks of breast cancer screening among older women, in order to help primary care providers more effectively advise their elderly female patients in the decision-making process.
The Breast Cancer Screening Debate
There is strong consensus among expert advisory groups (the US Preventive Services Task Force,1 the American Cancer Society,2 the American College of Obstetricians and Gynecologists,3 the American Academy of Family Physicians,4 and the American Geriatrics Society5) that mammography is to be recommended to screen for the early detection of breast cancer in women between ages 50 and 75. However, a recent review of the randomized controlled studies on which these recommendations were based suggests that the benefits of mammography may be relatively minimal, and that the risks for overdiagnosis and overtreatment may be significant.6 None of these trials enrolled women older than 74, so further information is needed to make evidence-based decisions regarding breast cancer screening for the older woman. Currently available evidence for such decision making is limited to observational or retrospective analyses.6
Women 75 or older have a greater risk than younger women for breast cancer, but older women are also at greater risk for dying of another disease—even those who have breast cancer.7,8 Thus, as with any health screening, it is advisable that a woman’s health status be carefully considered before screening decisions are made.
Breast Cancer in Older Women
Breast cancer incidence increases with age. Almost half of all invasive breast cancers and breast cancer deaths occur among women 65 and older, and almost one-quarter of all invasive breast cancers occur in women age 80 and older.9 Approximately one in six women diagnosed with breast cancer dies of the disease within 10 years.10 Once the cancer has metastasized, median survival time is two to four years. Older women have about a 1% chance of dying of breast cancer in a 10-year period.11
At the same time, older women are more likely than their younger counterparts to have comorbid illnesses—conditions that can compete with breast cancer as a cause of death and increase treatment-related morbidity. Older women with breast cancer and two or more other comorbid diseases are 20 times more likely to die of one of these diseases than of breast cancer.8
Use of Mammography in Older Women
Regular mammography has been shown to help detect tumors that are smaller and at an earlier stage of development than would be identified without this screening.8 Women who undergo regular mammograms have been shown to outlive those who do not, provided they live for at least five years after starting screening.12
Life expectancy for older women is often underestimated. The average 75-year-old woman has 12 more years of life expectancy, and the healthiest 25% of 80-year-old women will live an additional 13 years.13 Most of these women do not receive regular mammographic screening for breast cancer. However, if health status and life expectancy were considered as screening criteria in addition to age, many of these women would qualify for mammographic screening.
Using the Surveillance, Epidemiology, and End Results (SEER) Medicare database to evaluate 12,358 women age 80 and older who had been diagnosed with breast cancer, Badgwell et al14 found that only 51% had had one or more mammograms within the previous five years. Biennial screening rates were 24% to 27% among women ages 80 to 84 and 14% to 23% among those 85 to 89. In this cohort of elderly women, the researchers found that regular mammographic screening was associated with detection of breast cancer at earlier stages and suggest that the low rates of screening in this age-group may represent a missed opportunity for early detection of disease.