Avastin and GI bleeding

[Ina3]

Has anyone experienced GI bleeding being on Avastin? My dad with Stage IV NCSLC and LMD is on Keytruda and Avastin. Three weeks After full brain radiation he experienced GI bleeding and doctors are saying its due to Avastin. I worry now cause was hoping that Avastin will help with his brain mets but if that is causing bleeding , now what is next?

Any advice would be appreciated.