I'd rather be wrong about mine than wrong about yours. I was thinking brain tumor. Yours is very operable as long as you move quickly enough.
My dad never even seemed to mind the teflon they put in behind his stomach. He was pretty spunky (well, spunky for an overweight senior) for a while before his brain finally exploded. The doctor said something about a massive stroke, but I think it was from all the stuff he knew.
ACK!!