I guess we firstly have to go back to "how did the vet make the diagnosis?". Have they performed a needle aspirate to determine this is "a significant" lump that requires removal as opposed to a fatty lump?
If they have, then the costs quoted may also included for a diagnostic of the lump removed to ascertain if it is benign or malignant. (Worth asking your vet to clarify this as could explain the slightly higher price you have been quoted to other members)
I'm afraid that many mammary tumours are malignant - so the success of the operation may depend upon firstly how soon this has been "caught" and secondly on how deeply the tumour is set within this body and it;s proxmity to other organs.
The good news is that from what you have described - this is a very early case...and it could still be benign but you need histology tests to confirm that..
Start weighing him daily both pre and post op as this will help you to ascertain if he is taking in enough food to keep his guts going. Be prepared to have to syringe feed and get gut stimulants from your vet for the first few days post op until he recovers eating his normal quanittes, and also ensure that he is discharged with appropriate daily pain relief (metacam).
Think about putting him in a small "hospital" cage on towels or fleece post-op so you can monitor his output and keep his wound clean
Just a few suggestions - please don;t hesitate to keep asking questions on your htread
Keeping all fingers and paws crosed here for Arthur
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