Ethics of surgical innovation to treat rare diseases

A gynecologist has referred you a 50-year-old woman with extensive intravenous leiomyomatosis. A tissue diagnosis of invasive low-grade malignancy is available, and the tumor extends into the renal and hepatic veins. You propose removing the tumor by hysterectomy, to be combined if necessary with an extensive venectomy. The patient has had multiple vascular procedures which have exhausted all her available autologous graft material. You will try to excise the tumor through a venotomy, but it is likely that reconstruction will require venous replacement with prosthetic material, for which you have chosen externally supported polytetrafluoroethylene. What is the ethical course of action?.