Impact of margin status on survival after surgery for sinonasal squamous cell carcinoma

Background Sinonasal squamous cell carcinoma (SNSCC) is the most common malignancy of the paranasal sinuses. Surgery is the mainstay of treatment, yet positive surgical margins (PSM) are common and the prognostic impact on overall survival (OS) is mixed. Given the heterogeneity of impact of PSM on OS within the literature, we hypothesized that extent of tumor extirpation (microscopic PSM vs macroscopic PSM) may play a role in OS. Methods Patients with SNSCC were identified in the National Cancer Database (NCDB, n = 7808). Of these, 4543 patients underwent surgery, 3265 patients underwent nonsurgical therapy. Kaplan-Meier curves were used to compare OS between negative surgical margin (NSM), micro-PSM, and macro-PSM cohorts vs patients undergoing primary nonsurgical therapy in a propensity-score-matched analysis. Multivariable analysis of factors associated with macro-PSM was also performed. Results One thousand thirty-three (22.0%) of the surgery patients had PSM, and approximately half (n = 521, 50.6%) of these had macro-PSM. When compared with nonsurgical treatment, propensity-score-matched results demonstrated improved OS in patients with NSM and micro-PSM (p < 0.001), but macro-PSM patients did not demonstrate improvement (p = 0.20). Tumor within the paranasal sinuses and advanced nodal classification (N2/N3) (odds ratio [OR], 1.18; p = 0.02; and OR, 15.09; p = 005, respectively) was associated with increased odds of macro-PSM on multivariable analysis. Conclusions We demonstrate that the degree of tumor extirpation correlates with OS. Macro-PSM did not confer a benefit to OS when compared with nonsurgical therapy, and factors including tumor location and advanced nodal status affect whether surgery will result in macro-PSM. Given these findings, informed, shared decisionmaking between patient and surgeon regarding nonsurgical alternatives should occur before electing to proceed with surgery in SNSCC.