The word on the flatpick list is it was not throat cancer, but some sort of chronic inflammation of the vocal cords brought on by singing as much as he did with the voice forced up into a tenor range. I suspect it was aggravated by cigareets, but the claim that wasn't the primary cause.

Recent posts have indicated that he is now singing a few baritone parts at gigs with a group, after several years of not being able to sing at all.

All the above is second (at least) hand, however.

Peter.