Blinky! That's what I immediately thought of and was hoping for. That or a two headed massive catfish!
As everyone before mentioned, those guys do get huge on their own. I wonder if the reason they are finding them there at this size had nothing to do with them being mutated. Maybe, its because people are too afraid to catch, eat or mess with the fish there because they possibly are somewhat radio active. Just letting these guys grow to their natural lengths is unheard of anymore, and we're not used to seeing them get to these lengths.