This sounds exactly like what my husband has but he has never had cancer (maybe he does now). Right after Christmas I started smelling this putrid smell on him when he'd come down from working in the attic and I thought maybe it was chemicals but then it continued to get worse and worse to the point that, now, I make him bathe and change clothes at least twice a day and I wash the bed linens every day and won't even let him sit on the furniture until he's fresh out of the shower. It is definitely not B.O. but one of the worst smells I've smelled in my life. I literally, seriously threw up this morning because it is just overwhelming. The worst part is that it just hangs in the air for hours even after he's left the house. I can't handle it and I'm truly afraid I may have to leave a 16-year marriage if we can't find a cure. My kids say they don't smell it though which is almost certainly impossible. He just had an ultrasound of his kidneys which came back normal. I'm very, very concerned.