We're so sorry to hear about your rat! We'd love to help you any way we can, but questions regarding specific treatment will require that you call us directly at 816-363-4922.
Post your concerns on the nextdoor app. There are thousands of people in your community also have rats and are animal lovers that could help you out with this question. You may even be able to help raise some funds to help you with the surgery. Aid Animal hospital is fantastic. But surgery can be expensive as expected. Tumor removal on a very small animal may not cost as much as you think. Depending on your budget. Post on Nextdoor.
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