It is not all that common, but it can happen with the rabies vaccines as well as the feline leukemia vaccine (the first identified culprit.) Therefore, my best friend who is also a vet, recommends for inside-only kitties:

* No feline leukemia vaccine
* 3-year Rabies vaccine instead of 1-year
* Give any vaccines low on back leg, in case tumor develops and amputation is required. (Loss is easier for cat to adjust to than loss of a front leg/paw.)


** NOTE: this advice is for STRICTLY indoor-only, no contact with others. cats! ***

This is the method I've been following with my indoor-only girls. It's six years now, and no problems with tumors at all.

Catwoman