Too old for treatment?

TRACIL593 asks: "The other day I noticed two lumps about the size of a pea, on my Persian cat's tail. She is about 16 1/2 years old. I took her to my vet, who said that the lumps could be anything. She did not want to biopsy, because she felt that at her age she would not survive the anesthesia. My vet felt that my cat had outlived her life expectancy, and even if it is cancer to just let her live her life out. Other than the lumps my cat is in great shape for her age. I am wondering if there is any other way to diagnose the lumps such as aspiration, or through blood work? Is my cat too old to have the lumps removed?"