[Sinonasal undifferentiated carcinoma: 2 cases report].

Sinonasal undifferentiated carcinoma happens rarely, the clinical manifestations of the disease lacked specificity, with nasal obstruction and blood mainly in a unilateral nasal cavity. Two casas were reviewed, one case of tumor located in the middle of inferior turbinate; 1 in the bottom wall of the anterior nasal cavity. The tumor appeared dark red and unsmooth surface. Sinus CT scan showed occupying shadow and significant bone de struction. Complete resection of the lesion was performed. The pathology of neoplasm showed small-medium sized oval nuclei, high nucleus to cytoplasm ratio, and active mitosis. The pathological diagnosis was undifferentiated carcinoma. Comprehensive treatment of postoperative radiotherapy and chemotherapy were given distant metastasis still happened. One survived in 2 years of follow-up, 1 patient died in 18 months.