My sister in law's cat was a very butch 'husky' male. Long hair, gorgeous. He suddenly lost half his weight and became very docile. SIL basically left him to die, but I had a soft spot for him, and took him to the vet. Liver cancer, he's got 6 weeks at best. Surgery was possible, but would cost $$$. SIL would never bother. I made a jug of water, 4 litres water and put one oz of 35% food grade H202. Put some of this solution in his drinking water daily. He began to throw up daily, but kept gaining weight! His fur became thick again, one happy fat kitty. I believe he was 'throwing up' the cancer in a healing crisis. Whatever he was throwing up, it didn't look like his food, and it was nasty. This was 6 months ago. He's just well again.