Cancerous Carp?

Here are a few carp pictures from my last outing. The text that describes this trip is actually in the previous post. Two of these images depict a carp that has a very large growth just back of its operculum on its right side. The fish appeared to be very sickly - practically walked right up to me after I hooked it... kind of sad, kind of eerie... not sure just what happened to the fish - if anyone has an idea, please share. It's fairly common to see wounds and small growths - even evidence of disease in fish, but I've never seen anything this extreme. The other fish is representative in size of a large percent of the legions of carp that populate this river stretch.