Comparison of Surgical Outcomes of Robotic and Conventional Approaches in Patients with Pre- and Poststyloid Parapharyngeal Space Tumors

Background Benefits and drawbacks of robotic surgical approaches for parapharyngeal space (PPS) tumors remain undetermined. The purpose of this study is to compare surgical outcomes of PPS tumor patients who underwent robotic surgery with those of patients who received conventional surgical treatment. Patients and Methods We retrospectively analyzed clinicopathologic data from 136 patients who underwent surgical removal of PPS tumors via conventional or robotic approaches. Results We identified PPS tumors in pre- and poststyloid regions in 87 (64%) and 49 (36%) patients, respectively. There were 48 (35.3%) pleomorphic adenomas, 36 (26.5%) schwannomas, and 24 (17.6%) paragangliomas. Conventional surgical techniques were performed in 83 patients, and robotic surgical approaches were administered to 53 patients. Transcervical-parotid and transcervical approaches were most commonly performed in conventional surgery, while transoral and retroauricular approaches were the preferred surgical methods in robotic surgery for pre- and poststyloid PPS tumors, respectively. Robotic surgery resulted in less estimated blood loss during poststyloid PPS tumor surgery. Postoperative cranial nerve complications were noted in 36 of 83 cases (43.4%) in the conventional surgery group and in 17 of 53 cases (32.1%) in the robotic surgery group. Intraoperative tumor spillage of pleomorphic adenoma showed no significant differences between the two groups (13.6% in conventional vs. 15.4% in robotic surgery). The mean follow-up time was 4.9 +/- 3.4 years, and recurrences were observed in two patients during follow-up without a significant difference between the two groups (4.5% in conventional vs. 3.8% in robotic surgery). Conclusions Robotic surgery in PPS tumors is feasible through transoral, retroauricular, or combined approaches and provides treatment outcomes comparable to those of conventional open surgery.