Undifferentiated sarcoma of the maxillary sinus: report of a rare case in an adult.

A 51-year-old man complained of left facial swelling and recurrent nasal bleeding. A giant solid tumor in the left maxillary sinus was detected on head CT and MRI, and this tumor was destroying the maxilla and extending into the orbit, pterygoid muscle and posterior paranasal sinuses. The resected specimen consisted of spindle cells containing necrotic material. Histological examination revealed immature tumor cells, and immunohistological study of the tumor showed staining was only positive for vimentin. We accordingly diagnosed undifferentiated sarcoma in the maxillary sinus. Combination chemotherapy with vincristine, doxorubicin, cyclophosphamide/ifosfamide with mesna and etoposide was administered; however, the tumor was unresponsive and the patient died after around 3 months.