I have three albino cories, 1 I have had for about 2 yrs and he has a third chin now and what looks like fat along the bottom of the dorsal fin. He also has a good size belly. I'm going to try for a picture later.
A picture would be great, it doesn't look like it could be a tumor or anything like that could it? Also, are you sure it is an albino, I've seen green corys listed as albinos before and the green corys aren't "true" corys and can get alot bigger than a normal cory, just an idea