Nodal metastasis in surgically treated sinonasal squamous cell carcinoma

Objectives Tumor factors such as subsite and stage impact the risk of lymph node metastasis (LNM) and overall risk in sinonasal squamous cell carcinoma (SNSCC). We sought to identify the rates of patients presenting with or without clinical LNM for different tumor subsites and stages of surgically-treated SNSCC, determine the concordance between clinical and pathologic LNM after neck dissection (ND), and identify predictors of occult LNM. Methods The National Cancer Database was queried for patients with surgically-treated SNSCC from 2004 to 2016. For patients presenting with clinical LNM, rates of pathologic LNM and node negativity were determined following ND. For patients without clinical LNM, rates of elective neck dissection (END) and occult LNM were calculated. Predictors of occult LNM were identified using multivariate logistic regression. Results 1,964 patients were included; primary tumor subsites included nasal cavity (55.7%), maxillary (37.8%), and ethmoid sinuses (6.5%). Clinical LNM rates at presentation were 14.3% overall and 25.3% for the maxillary sinus; clinical LNM rates increased with tumor stage. 30.8% of patients with clinical LNM were pN0 following ND. Only 15.3% of patients underwent END; advanced age (> 75 years) (OR 8.17 [1.59-64.7]), presence of lymphovascular invasion (LVI) (OR 8.68 [2.63-30.2]) and unknown LVI status (OR 4.48 [1.17-16.2]) were associated with significantly higher risk of occult LNM. Conclusions Rates of occult LNM differed by subsite and tumor stage for surgically managed SNSCC. Rates of occult LNM were increased with older age and presence of LVI. Additional studies are necessary to determine the benefit of END in SNSCC.