After surgery a second biopsy is done to measure any changes in the chemicals being produced in response to the surgery. For this biopsy, patients are assigned to one of two groups - one group has the second biopsy within 3 hours of surgery, before taking the rescue drug, and the other group returns to the clinic the next morning for a biopsy 24 hours after surgery. Patients in the second group leave the clinic after surgery with two pain medications (tramadol and the study drug) and forms to record pain ratings at home. They are permitted to take only the pain medications provided and only at certain times.