Evaluation of breast risk at menopause: what impact on the use of menopausal hormone therapy?

A key concern with menopausal hormone therapy is the potential duration-dependent increase in breast cancer risk. Despite using progestogens (micronized progesterone and dydrogesterone), associated with the lowest risk, a slight increase in risk is still observed over 6 years of treatment. This increase in breast cancer concerns estradiol receptor-positive breast cancers and is consistent with a promoter effect on preexisting lesions. It is thus recommended to select patients according to their level of breast cancer risk before indicating menopause hormone therapy or preferring nonhormonal alternatives. A very high risk is being a carrier of a pathogenic variant or having a strong history of breast cancer in the family that occurs at a young age. Women biopsied with atypical hyperplasia, having benefited from thoracic radiotherapy at a young age, or with high breast density, are also at high risk of breast cancer. Lower-risk factors include reproductive and lifestyle factors. Some scores can, albeit imperfectly, help evaluate a woman's risk category and the probability of carrying a pathogenic variant. The IBIS score, Gail score, and CANrisk are the most commonly used tools for risk stratification. Various scientific societies have based their recommendations on the limitations of menopausal hormone therapy, depending on risk category. Discussions with the patient and lifestyle improvements can help modulate and tailor these recommendations.