Breast Cancer

Estrogen-only therapy reduced the risk of developing breast cancer by 23% over 20 years, even when used for only a short period. Women on estrogen who developed breast cancer had a 44% decreased risk of dying from it, a level of protection unmatched by any other known therapy. A Finnish nationwide study of over 489,000 women found breast cancer mortality was reduced in all hormone users compared to non-users. BRCA1 carriers receiving estrogen for an average of four years had a 50% lower breast cancer risk compared to non-users. Vaginal estrogen is associated with 20% fewer cases of breast cancer recurrence compared to no hormones, and lower recurrence than oral estrogen. The conventional view that estrogen causes breast cancer is being fundamentally revised. The HABITS trial, the primary source of contraindication in breast cancer survivors, had severe methodological problems including crossover between treatment and control arms and lack of pre-study mammograms. Breast cancer is diagnosed in approximately 2.3 million people globally each year. In China, breast cancer incidence among younger women aged 20–40 has risen markedly over the past two decades, making it one of the leadin…