Prognostic Determinants in De Novo Sinonasal Squamous Cell Carcinoma: A Retrospective Study

Abstract Objective Patients diagnosed with de novo sinonasal squamous cell carcinoma (DN‐SSCC) generally present at an advanced stage and have a poor prognosis. The study aimed to summarize and analyze the outcomes of DN‐SSCC patients. Study Design Retrospective cross‐sectional study. Setting Single‐center clinical database. Methods Overall survival was assessed with Kaplan‐Meier analyses and Cox proportional hazard regression analyses for patients diagnosed with DN‐SSCC between 2010 and 2018. Results Long‐term follow‐up was completed for 85 out of 112 patients. The distribution of cancer stages was as follows: 1.8% in stage Ⅰ, 7.1% in stage Ⅱ, 23.2% in stage Ⅲ, and 67.9% in stage Ⅳ. Ocular invasion was present in 50.9% and intracranial invasion in 23.2%. Significant intergroup differences in T‐stage ( P = .009) and clinical stages ( P = .028) across therapeutic modalities. The 1‐year and 5‐year overall survival (OS) rates were 83.5% and 51.4%, respectively. Factors significantly associated with prognosis included age ( P = .048), lymph node classification ( P = .003), clinical stages ( P = .002), ocular invasion ( P = .035), therapeutic modalities ( P < .001), and resection margin status ( P = .005). Surgery followed by adjuvant chemotherapy or/and radiotherapy (Surgery + CT/RT) demonstrated best prognosis, with a 5‐year OS rate of 71.9%. Margin status significantly impacted survival outcomes (5‐year OS: 56.0% negative margin versus 29.0% positive margin) (log‐rank P = .005). Lymph node classification (HR 4.927, 95% CI 1.296‐18.733; P = .019) and preoperative induction chemotherapy combined with surgery (ICT + Surgery) (HR 0.048, 95% CI 0.004‐0.574; P = .017) were independent prognostic factors for DN‐SSCC. Conclusions Patients receiving Surgery + CT/RT had better prognoses. This therapeutic modality is recommended for advanced‐stage patients, especially those with positive resection margins.