goldfish with lump on head

Question
I have a fancy goldfish that I've had for about 2 years, and it has now developed a lump on its head.  The lump is pale orange to white and about the size of a small pea. It isn't getting any better or worse at the moment.  My local fish shop were of no help.
Thanks

Answer
Nina,                                                        He may have just injured himself. Lets give him some tetracycline. This is broad spectrum antibiotic and see what happens. Don't forget to remove your carbon while you treat him for 7 days. Then a 25% water change and new carbon. If it starts to go down in size great. If not it may be a tumor. I am so sorry if it is. They are usually fatal, but don't be to sad yet sometimes they can live with them for quite awhile. Lets see how this goes first. If he is swimming and eating don't worry. If it doesn't go away and he starts having real problems get back to me and we will go from there. Good Luck, Tina