Accounting for up to 10% of all feline cancers, oral cancer is an important and deadly disease for cats. As in humans, squamous cell carcinoma (SCC) is the most common type of oral cancer in cats, comprising 60-70% of reported cases. Most commonly involving the bone of the upper or lower jaw and the tongue, feline SCC typically progresses very rapidly. Treatment of feline oral SCC with surgery, chemotherapy, and/or radiation therapy has yielded poor results, with typically less than 10% of affected cats living longer than one year. Recent findings in dogs and people indicate that nonsteroidal anti-inflammatory drugs (NSAIDs), a class of drugs that includes aspirin, may be effective in the treatment of certain types of cancer, including SCC. These drugs may help kill cancer cells, decrease the growth of new blood vessels into tumors, or enhance the body’s immune response to cancer cells. Piroxicam is one drug in this class of NSAIDs that has been shown to hold particular promise in the treatment of cancer. Mitoxantrone is an injectable chemotherapy agent that has also been found to be beneficial in the adjuvant treatment of SCC. Recently, a study in dogs with bladder carcinoma indicated that combination of piroxicam with mitoxantrone may provide responses superior to piroxicam alone. In fact, the combination nearly doubled the survival time compared to dogs treated with piroxicam alone. This study is designed to evaluate the clinical efficacy of piroxicam alone, compared to piroxicam and mitoxantrone, for treatment of oral SCC in cats. It is hoped that one-year survival times will increase from 10% to 50% of treated cats.