This week’s Case Record of the Massachusetts General Hospital is An 85-Year-Old Woman with Mammographically Detected Early Breast Cancer.
Randomized trials have confirmed improved survival in women 40 to 70 years of age who undergo annual or biannual screening mammography, but only sparse and conflicting data are available pertaining to women older than 70 years.
• Is mammography useful for screening older women for breast cancer?
The sensitivity, specificity, and positive predictive value of mammography for detecting breast cancer increases with age, because ductal tissue is replaced by fat, resulting in an increase in the radiolucency of breast tissue. One study of women 80 years of age or older who underwent mammography on a regular basis showed that breast cancer was detected at a lower stage and was associated with a higher rate of breast-cancer-specific survival. In addition, however, deaths from other causes were lower in this group, which suggests a bias for screening mammography among healthier patients.
• When should screening for breast cancer among older patients be discontinued?
Since the precise age at which to discontinue screening mammography is uncertain and guidelines from major panels and organizations are conflicting, using life expectancy and not age as the basis for recommending screening appears to be the most prudent approach. Since prospective controlled trials are unlikely to be performed in elderly patients, a reasonable option would be to offer yearly screening to women without major coexisting conditions and with an estimated life expectancy of at least 5 years.
Morning Report Questions
Q: Is there a role for aromatase inhibitors in the treatment of older women with hormone-receptor-positive breast cancer?
A: The most recent meta-analysis of trials of adjuvant therapy by the Early Breast Cancer Trialists’ Collaborative Group showed that adjuvant tamoxifen therapy, as compared with no tamoxifen treatment, significantly improved both relapse-free survival (decrease in the absolute annual risk of recurrence, 54%) and overall survival (decrease in the absolute annual risk of death, 34%) in women 70 years of age or older with early-stage, hormone-receptor-positive breast cancer. In postmenopausal women, adjuvant therapy with aromatase inhibitors (anastrozole, letrozole, and exemestane) has shown significant improvement (approximately 3 to 5%), as compared with tamoxifen, in relapse-free survival but not in overall survival.
Q: Is there an advantage in using aromatase inhibitors rather than tamoxifen for older women with hormone-receptor-positive breast cancer?
A: Unlike tamoxifen, aromatase inhibitors are not associated with endometrial cancer or thromboembolism, but their use does increase the risk of fracture. Oral bisphosphonates can be effective in preventing or minimizing further bone loss in women treated with aromatase inhibitors. However, aromatase inhibitors are expensive.