University says women should be advised of their Breast Density!!

I never knew of the connection between dense breast tissue and breast cancer. I had dense breasts and cysts. My cancer cells were aggressive.  lump 2cm, no lymph involvement. Surgery, chemo  radium and now tamoxifen. My cancer was found at my mammogram and ultrasound annual check. I also didn't know tamoxifen reduces breast density and there has been some discussion that it could be used at a preventive for women that have dense breasts.