Ah i see. well thats good to hear! i have never had a pet with any type of cancer so its really hard for me to say whether or not you could be over reacting. but in my opinion (because im like this with my animals) any change in normal behavior should be looked into. there is always something behind it even if its nothing life threatening.
Definitely did not know about fish and mast cells! learn something new every day. i think by principle for cats and dogs avoiding fish is good because of the high risk of toxins in fish and the addictive nature it has for kitties. i try to avoid it if i can.
