Hello. I had Gamma Knife in March 2024. My surgeon told me at that time. The procedure would keep the tumor from progressing and that it may take years to see if it gets smaller. That is why (when it was accidentally discovered) they wait to monitor the growth. It was a terrifying and amazing procedure rolled all into one. Walk in to UofP at 6:00 am and walk out at 3:30pm. No side affects at all. I only had the tiny little holes from the halo that had to heal.