**4. Breast cancer biology in elderly patients**

Most available publications report that breast cancer in older women is less aggressive. In this group, hormone-dependent cancers are diagnosed more frequently, and overexpression of the HER2 receptor, grade 3 cancers, and high Ki67 values are less common.

The odds of developing triple-negative cancer in women aged <40 years are 1.53 times higher than in patients aged over 60 years, but 15–18% of older patients are diagnosed with this breast cancer subtype, which confers a poor prognosis [12].

Age does not significantly affect the cancer's histological subtype, but lobular, mucinous, and papillary carcinomas are slightly more common in older patients. For example, mucinous carcinomas account for 4–6% of cancers diagnosed over the age of 75 years, whereas only 1% of premenopausal women are diagnosed with this type of cancer [12, 13].
