A biopsy is a medical test involving sampling of cells or tissues for examination. This usually entails pre-anesthetic testing and anesthesia in order to get an adequate sample to submit to the laboratory. In some cases, we may choose to do a needle aspiration while the animal is awake to get a small sample to examine here in the hospital. This quick test can help us to determine if further treatment or surgery is necessary. Occasionally, we may need to send your pet to a local referral hospital for the biopsy if the surgery is especially complicated.