Specifically, this pilot study seeks to evaluate the feasibility of determining whether celecoxib treatment inhibits COX-2 expression, alters the intratumor eicosanoid profile, and/or suppresses markers of proliferation and growth in human tumor tissues. In addition, this trial aims to evaluate the feasibility of reliably measuring the effects of celecoxib treatment on biomarkers of angiogenesis, prostaglandin metabolism and select growth factors. The study is titled: "Molecular effects of short-term celecoxib treatment on head and neck squamous carcinoma." In this study, 10 patients identified in the Head and Neck Surgical Oncology clinic at MSKCC with untreated squamous cell carcinoma of the oral cavity or oropharynx will be recruited to participate. Participation will not change the standard of cancer care that the patients receive. At the initial office evaluation the tumor will be biopsied. Blood and urine will also be collected. Patients will then take oral celecoxib (400 mg) twice daily starting exactly 5 days prior to staging examination under anesthesia or definitive resection and including the morning of surgery. The tumor will then be re-biopsied at the time of staging examination under anesthesia or surgical resection. Blood and urine will similarly be re-collected at that time.