Hi Danica,
This is a great question, so thanks for the submission. I always recommend investigating any lump or bump you find on your pet, no matter how long it has been there. We cannot definitively determine the identity of a mass just by visual inspection and palpation (feeling it). We need to take some samples and examine the cells that make up the mass in order to appropriately identify it.
The first test that is typically recommended is called a fine-needle aspirate. For this test, a needle is inserted into the mass and a syringe is attached to aspirate (suction) some cells out. This test allows us to get an idea of the cell type inside the mass when we examine them under the microscope. Some masses give us enough clear cells from this technique to make a diagnosis, while others can be more elusive.
If an aspirate does not give a clear diagnosis, the next step would be a tissue biopsy. This is different from an aspirate in that we take a piece of the mass, preserve it, and send it to the lab to have a pathologist process and review. A biopsy is always more definitive because the pathologist can see how the abnormal cells are growing and behaving. She can tell what type of cell they are, how abnormal they are, how quickly they are multiplying and if they are invading surrounding normal structures. All of these things help to determine if a mass is benign or malignant (cancerous). Biopsies can be either incisional (a piece is taken) or excisional (the whole mass is removed). Your veterinarian will be able to guide you further on the best diagnostic approach for your cat, but hopefully this gives you an idea of what to expect.
Regarding your concerns about her age and the risks of any procedure – so long as a pet is otherwise healthy, advanced age alone is not a contraindication to performing diagnostic or surgical procedures. Before proceeding with a work-up on the mass however, a thorough physical exam, as well as bloodwork and a urinalysis would be a good idea to ensure she is healthy enough to handle any procedure that may be needed. I hope this information is helpful for you.
Sincerely,
Dr. Kim Hester
