I agree fully with what Christina has wrote. Healthy piggies arent the best under anestic so an older pig would be a great risk.
I wouldnt let the vet force you into doing anything with her, if the lump causes pain or distress please think is it worth putting her through the operation and having her pts. I had a sow a couple of years ago with a mass on her throat, it turned out to be a tumour and she was pts at only 3yrs old.

Emma x

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