Cancer Metastasis to the Sinonasal Cavity: Clinical Characteristics and Survival Analysis in 35 Patients.

ObjectivesSinonasal metastases are far rarer than primary sinonasal malignancies, hence seldom reported or analyzed in existing literature. To address these gaps, we have retrospectively analyzed 35 patients with sinonasal metastasis in a single university hospital in South Korea, over a 24-year period.MethodsFrom 1998 to 2022, among 11,814 pathology reports of sinonasal tissues, 35 (0.3%) were identified with sinonasal metastasis from solid organ cancers. Patients' clinical characteristics, presentation, primary tumor profiles, treatment modalities for the sinonasal metastasis, and overall survival (OS) were retrospectively reviewed and analyzed, in addition to the literature review.ResultsHepatocellular carcinoma (HCC) was the most common primary cancer (37.1%), followed by lung (14.3%), breast (11.4%), and thyroid (8.6%). The most common presentation was epistaxis (20%), however, 20% were identified incidentally. The nasal cavity (37.1%), sphenoid and maxillary sinus (31.4%), and skull base (34.3%) were the most prevalent metastatic locations. Although the median OS following a sinonasal metastatic diagnosis was 7.0 months, patients with isolated sinonasal metastasis, thyroid cancer- metastases, or definitive therapy for sinonasal metastasis had significant longer OS (p=0.037, 0.035, and p-trend=0.003, respectively).ConclusionIn our study, HCC was the most common primary cancer for sinonasal metastasis, contrasting with renal cell carcinoma prevalence in Western literature, suggesting that regional cancer incidence variations may influence sinonasal metastasis epidemiology. Despite the poor prognosis in general, in selected patients with thyroid cancer or solitary sinonasal metastases, the definitive treatment for the sinonasal metastasis may aid in an increased duration of survival.