The risk of breast cancer is moderately elevated in current and recent hormone replacement therapy users, with an approximate 2.3% excess risk per year of use. Some excess risk has also been reported for ovarian cancer in long-term users. Unopposed oestrogens are strongly related to endometrial cancer risk, but cyclic progestogen addition appears to reduce this side effect, possibly further increasing the risk of breast cancer. There is a moderate inverse association between colorectal cancer and hormone replacement therapy. Most potential favourable and adverse effects of hormone replacement therapy on cancer risk are restricted to current users. Selective oestrogen receptor modulators may offer advantages in reducing breast cancer risk. Regular aspirin use and high levels of physical activity induce a moderate reduction of risk for colorectal, and possibly for breast, ovarian and endometrial cancer. Overweight and obesity are strongly related to gallbladder, endometrial and breast cancer, and appear to be also related to colorectal, renal, pancreatic and ovarian cancer.
- Hormone replacement therapy
- Nonsteroidal anti-inflammatories
- Physical activity
ASJC Scopus subject areas
- Obstetrics and Gynaecology