Trends in Positive Surgical Margins in cT1-T2 Oral Cavity Squamous Cell Carcinoma

Objectives/Hypothesis To evaluate trends in contemporary positive surgical margin incidence in cT1-T2 oral cavity squamous cell carcinoma and to evaluate factors associated with surgical margin status. Study Design Retrospective analysis of large dataset. Methods Retrospective analysis of the National Cancer Database. Results Between 2004 and 2016, 39,818 patients with cT1 or cT2 oral cavity squamous cell carcinoma received primary curative-intent surgery. Positive surgical margins were present in 7.95% of patients, and univariable adjusted probability of positive surgical margins over the study period declined by 1% per year (odds ratio [OR], 0.99; 95% confidence interval [CI], 0.98-1.0; P = .049). Multivariable regression revealed the annual rate of positive surgical margins declined significantly (OR, 0.95 per year; 95% CI, 0.92-0.97; P < .001). Factors associated with increased odds of positive surgical margins included cT2 disease, subsite, understaged disease, lymphovascular invasion, tumor grade, and positive lymph nodes. Race and socioeconomic status were not associated with surgical margin status. Treatment at an academic center was associated with increased time to definitive surgery (median 35 days IQR 22-50 vs. median 27 days IQR 14-42; P < .001) and a 20% reduction in positive surgical margin rate (OR, 0.80; 95% CI, 0.71-0.90; P < .001). Treatment at high-volume centers was less likely to be associated with positive surgical margins (OR, 0.85; 95% CI, 0.74-0.98; P = .02). Conclusion Surgical subsite, clinical T and N category, presence of lymphovascular invasion, and histologic grade were independent predictors of positive surgical margins. Patients are increasingly being treated at high-volume and academic centers. Overall, the rate of positive surgical margins in cT1-T2 oral cavity squamous cell carcinoma is decreasing. Level of Evidence 4 Laryngoscope, 2022