Prostate Cancer and Memory Difficulties

Can anyone help me with this please? My husband has PC and one of the side effects seems to be that its making him more forgetful - noticably so. Its ok at home in as much as I simply (!) do all his remembering for him but its starting to affect his work. My husband is 59 so its not dementia or anything like that.  Has anyone else had this problem? Im also wondering if there are any memory exercise programs out there? thanksLynne...