Chondrosacroma of the skull

Anyone here have a chondrosacroma of the skull ? I have been researching so hard for my husband who has a piece of the tumor too close to his curated artery and could not be removed after surgery . It’s stage 2/3 . We are having a pet scan because two years post surgery , the doctors have noticed a change in growth .😢 We are told our options are limited . There is a drug called Ivosidenib, they could put him on , but it still
has not been proven to stop the growth. I am very worried. Any help would be appreciated.