: Metastases to the sinonasal tract are rare but occur for many malignancies. The demographics of sinonasal metastases in Korea aren't well known. Methods : Nine cases of metastases to the sinonasal tract identified at Asan Medical Center from January, 1995 to December, 2007 were reviewed. Results : Metastatic carcinomas accounted for 2.4% of sinonasal malignancies and 4.7% of carcinomas. Six kinds of cancer metastasized to the sinonasal tract. They included hepatocellular carcinomas (nasal

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... ty and maxillary sinus), colonic adenocarcinomas (sphenoid sinus and maxillary sinus), clear cell renal cell carcinoma (nasal cavity), pulmonary small cell carcinoma (nasal cavity), follicular carcinoma of thyroid (sphenoid sinus), and breast ductal carcinoma (maxillary sinus). Primary sites had been known in 7 cases, but follicular carcinoma and one adenocarcinoma were diagnosed after sinus metastases. Histologically, they had ill-defined borders and involved both mucosae and bones. Microscopic findings were not different from those for the primary tumors. Conclusions : The pattern of sinonasal metastases in Korea are different from western data regarding incidence, site, and type, with hepatocellular carcinoma and the nasal cavity being the most common type and site, respectively. Awareness of the possibility of metastases and their pattern is encouraged when examining sinonasal tumors.