Now and Future of TORS in the Management of Recurrent Nasopharyngeal Carcinoma

Abstract

Nasopharyngectomy has been shown to be an effective salvage for local recurrence of nasopharyngeal carcinoma (NPC) after radiotherapy. Various approaches for open nasopharyngectomy have been described but all approaches required a facial incision and transgress a significant amount of normal tissue. With the advance of endoscopic surgery, several authors have described endoscopic nasopharyngectomy. Due to the lack of instruments to turn around corners and difficulty of manipulating tissue in a tight space, endoscopic nasopharyngectomy is not an easy operation. The advent of the surgical robot introduced several advantages for use in the nasopharynx, including 3-D magnified vision and the ability to perform complex wristed movements in a tight space by the endowrist of the robot. In order to adapt the da Vinci surgical robot for transoral robotic nasopharyngectomy, the robot need to be docked from the head of the patient. The nasopharynx can be approached with a midline palatal split, lateral palatal flap or a palatal suspension approach. Due to the lack of tactile sensation of the robot, dissection around the internal carotid artery in the parapharyngeal space is not advised. Therefore tumours should be 1cm away from the internal carotid artery to avoid inadvertent injury to the vessel. Combining with endoscopic drills and burs, the roof of the nasopharynx and the floor of the sphenoid can be resected enbloc if necessary. Early results of the author’s current cohort of 26 patients showed a 83% 2-years local control rate with a mean operating time of 234 minutes. A new generation of surgical robots like the Flex Robot or da Vinci SP are now available or soon be in the market. These new robots are designed for transoral use and should improve the delivery of the robotic arms to the nasopharynx, without resorting to splitting the palate. Early cadaveric experiments showed promising results with the new robots.