My Cat is losing alot of Weight

My Cat in the last year has lost alot of weight. From Weighing 13 lbs to now only 8. My cat is skin and bones and I am frantic to have him gain some weight. I brought him to two vets. One that said nothing is wrong with him because he doesn't have parasites. Then I was not satisfied by what he had to say so I went for a second opinion. The second opinion said that he thinks it's cancer but he did an xray of his chest and found nothing abnormal. He does have an injury on one of his outer digits but that happened 2 weeks ago, and he thinks the cancer is there. They are preforming a biopsy to see if there are cancer cells. He looks worse everyday. I will wait for the results but does anyone have an idea what else it could be. I just have a feeling it may be something else?

Answer by Kate
Did your vet take blood samples and check for a thyroid problem? I ask because a sign of a thyroid problem is loss of weight even though the cat continues to eat normally. It happened to my cat.

I would have assumed that any vet would have considered the thyroid. If not it may be worth mentioning, perhaps when they do the biopsy.

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