I have been on Prolia for the past 4 years- no side effects. I was diagnosed with stage 1 ER+ breast cancer in July. My endocrinologist who originally prescribed the Prolia said I couldn't be on a better drug for osteoporosis since Prolia has been shown to prevent cancer cells from going to the bones, which is one of the places breast cancer cells like to go.
He did tell me though that when I stop getting the injections, I would need to immediately follow up with something like Reclast or Evenity to prevent the risk of bone fractures from stopping Prolia.
I don't know how long he wants me to continue on Prolia, but I believe it is responsible for the lack of damage to my hip bone after a fall and a diagnosed hip fracture. I was able to heal completely after 6 weeks of non-weight-bearing on that leg.
I started taking anastrozole after my recent mastectomy and will see what my next bone scan will show in August. They told me that the bone loss, if any, would be very slow and they would have plenty of time to decide whether or not to switch me to tamoxifen.
Wishing you the best.