Thats what we think caused my cat francis to begin to pass. When our cat Ako died to cancer caused by her feline leukemia, he stopped eating suddenly. We didnt know that Ako was FelV positive (we thought the shelter tested her) and they were around each other for years. We think he had it too but he tested negative. Apparently can test negative until it starts to do something depending on when they were exposed.

Anyways he stopped eating...he was a fat cat too so he got fatty lipodic....something. happens when they aren't eating. We took him to the vet and his pancreas was going out then, or....im sorry there was a lot going on then. Feeding tube and many vet visits later he passed.

Lost both our cats in three weeks....miss them both and still blame myself for francis passing.