Association of Intraoperative Frozen Section Controls With Improved Margin Assessment During Transoral Robotic Surgery for Human Papillomavirus–Positive Oropharyngeal Squamous Cell Carcinoma

Abstract

ImportanceIntraoperative margin assessment is an important technique for ensuring complete tumor resection in malignant cancers. However, in patients undergoing transoral robotic surgery (TORS) for oropharyngeal carcinomas, tissue artifact may provide pathologic uncertainty.ObjectiveTo assess the benefit of providing frozen section control samples (“positive tumor biopsies”) for use during intraoperative margin assessment for patients undergoing TORS for human papillomavirus (HPV)-16–positive oropharyngeal squamous cell carcinoma (OPSCC).Design, Setting, and ParticipantsIn this cohort study, patients receiving curative-intent TORS for biopsy-proven HPV-16–positive OPSCC performed by a single attending surgeon (A.H.M.) at Ronald Reagan UCLA Medical Center from 2017 to 2021 were included in a retrospective data analysis. Exclusion criteria included HPV-negative status, participation in clinical trials, and tumors of unknown primary origin.Main Outcomes and MeasuresSurvival outcomes investigated included overall and disease-free survival. Adverse pathologic outcomes measured included occurrence of nondiagnostic margins and margin reversal from frozen to fixed pathology.ResultsOf the 170 patients included (mean [SD] age, 61.8 [9.9] years; 140 [82%] male), 50% of patients (n = 85) received a frozen section control. Use of a frozen section control was associated with statistically significantly improved sensitivity of intraoperative margin assessment, from 82.8% to 88.9% (difference, 6.1%; 95% CI, 3.9%-8.3%). Eleven percent (n = 18) of all tumors evaluated exhibited at least 1 nondiagnostic intraoperative margin, and 11% (n = 18) experienced margin reversal from frozen to fixed pathology. In patients with nondiagnostic margins, use of frozen section controls was associated with statistically significantly reduced time spent in the operating room (Cohen d, 1.14; 95% CI, 0.12-2.14).Conclusions and RelevanceIn this cohort study, frozen intraoperative margins assessed during TORS resections of HPV-16–positive OPSCC were diagnostically challenging. Adverse pathologic outcomes, such as margin status reversal from positive on frozen pathology to negative on formal analysis, were common. Providing intraoperative frozen section control biopsies may offer clarity in cases with nondiagnostic margins, reducing the need for additional sampling and time spent in the operating room.