Risk of Cancer With Hormone Replacement Therapy: A Narrative Review

Hormone replacement therapy (HRT) remains the cornerstone of menopausal symptom management, effectively alleviating vasomotor symptoms and genitourinary syndrome, whilst mitigating long-term risks such as osteoporosis. However, despite an increasing body of evidence on the relative safety of HRT, earlier studies that demonstrated an increased cancer risk have resulted in decades of controversy and reshaped clinical practice and public perception. Concerns around HRT are heightened in cancer survivors or those with strong family histories and genetic risks, and many clinicians remain reluctant to consider HRT due to the potential for promoting cancer. Globally, around 9 million women and an estimated 60 000 women in the UK under the age of 50 are diagnosed with cancer and will receive treatment that results in iatrogenic premature or early menopause or develop hormone-related, menopause-like, side effects, even if not rendered menopausal. Improvements in oncological management have resulted in significant benefits in cancer survivorship, and importantly, an increasing focus on quality of life. This article aims to comprehensively review the evidence and provide an overview for clinicians that can help guide discussions with patients regarding HRT risks and benefits, and promote shared, informed decision making.