My 86 year old husband has GMB 4. Inoperable but stereotactic biopsy done on 10/16/23. He had to wait 5 weeks for the surgical site to heal before beginning radiation. Longer than we expected, but began chemotherapy simultaneously. The initial treatments were very tough, but he is doing well now, 7 months down the road. Chemotherapy is to continue beyond the typical 6 cycles because his tumor continues to shrink. No known prognosis at this point, but it’s clear he’s doing better than expected. Praying that your father has a great response to treatment!