What your seeing on the pectorals are either an over production by the fish of breeding tuberculls which would be a case of "well hello you lucky ladies , arent I well endowed in the tuberculls",

"swim away girls"

.
He may also be on steriods
Joking aside it may well be something that is far more serious in that these could be what are called Papilloma's
Papilloma are similar in apearance to carp or fish pox with large areas of it appearing on the leading ray of pectoral fins, they like carp pox normally disapear as the water temperature rises
Papilloma may choose to reveal itsself by the appearance of tumors redish to pink in their appearance, these will have to be removed surgically by that of a vet in extreme cases where a large number of these need be removed secondary infection may very well set in which obviously will require another visit to the vet .
Dave