Breast cancer in women over 75 differs in several important ways from breast cancer in younger women, affecting how it develops, how aggressive it is, how it is treated, and the outcomes experienced by patients. Understanding these differences is crucial for tailoring screening, diagnosis, and treatment strategies to this older population.
First, breast cancers in women over 75 tend to be biologically less aggressive. Tumors in this age group are more likely to have favorable characteristics such as being hormone receptor-positive (estrogen and progesterone receptors), which means they often respond well to hormone therapies. These tumors also tend to have fewer positive lymph nodes, indicating less spread to nearby lymphatic tissue. Additionally, the metastatic spread—the process by which cancer cells move to other parts of the body—usually occurs more slowly in older women. This slower progression often results in a longer sojourn time, meaning the tumor grows more slowly and may remain localized for a longer period compared to tumors in younger women.
Because of this slower growth and less aggressive nature, breast cancer detected in older women may not always require the same aggressive treatment approaches used in younger patients. For example, adjuvant chemotherapy, which is chemotherapy given after surgery to reduce the risk of cancer returning, has shown limited survival benefit in women over 70 with hormone receptor-positive, HER2-negative breast cancer. Moreover, chemotherapy in this age group often causes substantial toxicity, which can significantly impact quality of life. Therefore, treatment decisions in older women often weigh the potential benefits of therapy against the risks and side effects, with a greater emphasis on maintaining quality of life.
Screening practices also differ for women over 75. While mammography screening is widely recommended for women up to age 75, the benefits of continuing routine screening beyond this age become less clear. This is partly because the life expectancy of women over 75 varies, and those with less than 5 to 10 years of expected life are unlikely to gain survival benefits from screening mammography. Additionally, some breast lesions detected in older women, such as ductal carcinoma in situ (DCIS), a noninvasive form of breast cancer, may never progress to invasive cancer within their lifetime, leading to potential overdiagnosis and overtreatment. Hence, decisions about continuing screening in women over 75 are often individualized, taking into account overall health, life expectancy, and patient preferences.
Symptoms and clinical presentation of breast cancer in older women may also differ slightly. While the classic signs such as lumps, changes in breast size or shape, skin dimpling, nipple changes, or discharge remain important, older women might be less likely to report symptoms promptly or may attribute changes to aging or other health issues. This can sometimes delay diagnosis. However, when breast cancer is diagnosed, it is often at an earlier stage due to the slower tumor growth, although this is not always the case.
From a molecular perspective, breast cancers in older women show distinct genetic and proteomic profiles compared to those in younger women. For example, mutations in genes like TP53 and PIK3CA are more common in luminal tumors (a subtype of breast cancer that is hormone receptor-positive) in older women, whereas younger women’s tumors may have different mutation patterns and tend to be more aggressive. These molecular differences influence tumor behavior and response to therapies.
Treatment approaches in older women must consider comorbidities, frailty, and the potential for treatment-related side effects. Surgery remains a mainstay of treatment for operable breast cancer regardless of age, but the extent of surgery and the use of additional therapies like radiation or chemotherapy may be adjusted. Hormone therapy is often favored for hormone receptor-positive tumors due to its effectiveness and generally better tolerance. Radiation therapy may be used selectively, especially if life expectancy is limited or if the risks outweigh the benefits.
In summary, breast cancer in women over 75 is generally characterized by less aggressive tumor biology, slower progression, and a higher likelihood of hormone recepto