I have personally found one in the past. I believe some catfishes swallow the hook so deep that some fishermen wouldn’t want to go through the hustle of trying to get the hook out. So they cut the line and sale the fish, while the hook remained inside.
Also, some catfishes swallow hook and cut the line with their teeth, before being later caught by another fisherman who wouldn’t know that the fish had previously swallowed a hook.
So, I made searching for hook a part of the catfish cooking routine, to be on a safer side.”