The Impact of "Close Margins" in HPV-Associated Oropharyngeal Squamous Cell Carcinoma Treated with TORS.

Objective: Margin distance is a significant prognosticator in oral cavity cancer but its role in HPV-related oropharyngeal squamous cell carcinoma [HPV(+)OPSCC] remains unclear. Here, we investigate the impact of margin distance on locoregional recurrence in HPV(+)OPSCC.

Study Design: This is a retrospective cohort study of surgically treated HPV(+)OPSCC patients. Patients received either standard of care (at least 60 Gy with or without cisplatin) or de-escalated adjuvant therapy (30-36 Gy with concurrent docetaxel). Margin distance was measured in mm from the primary specimen or in combination with separately submitted margins. Kaplan-Meier survival analysis with univariate and multivariable Cox regressions were conducted to determine the impact of margin distance on risk of local and locoregional recurrence.

Setting: Setting for this is 3 tertiary centers between January 2010 and February 2024.

Results: Among 1102 included patients, 33 (3.0%) had positive final margins. 374 patients had adequate margin distance data available. Margin distance was >3 mm in 73.4%, 1 to 3 mm in 24.5%, and <1 mm in 2.2% of patients. Positive final margins, pT4 disease, pN2 disease, and surgery alone as a treatment modality (P < .02 for all) was associated with higher risk of 5-year locoregional recurrence. Margin distance did not significantly impact risk of local or locoregional recurrence even after adjusting for de-escalated adjuvant therapy (P > .05).

Conclusion: Positive final margins after TORS without adjuvant radiotherapy for HPV(+)OPSCC carries a high risk of local recurrence. Margin distance does not appear to significantly impact risk of local or locoregional recurrence, even after de-escalated adjuvant radiotherapy.