Welcome! My name isXXXXX am a 2003 graduate, and currently a Medical Director of a veterinary hospital.
I am sorry to hear about this concern for Beauty.
That sounds like a pretty good deal.
Generally, a histopathology to evaluate a tumor at the laboratory can easily cost about $150-200 by itself. So, $450 for anesthesia and surgery isn't to bad for a tumor excision.
Try not to squeeze it! If a mast cell tumor, that just makes it more mad and creates ore inflammation. Also, every time it opens up, there will be a predisposition for infection.
If nearby, you could get a second opinion from a VCA hospital as a free exam.
Click on the below link and enter your zip code to the right. If you find a local Veterinary Centers of America hospital, their website will have a link to a free examination voucher. VCA hospital locator
(Disclosure: I work for a VCA hospital)I always appreciate hearing about any experiences if you find a local VCA hospital to assist you
I hope that information has been helpful.
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