True Malignant Mixed Tumor of the Maxillary Sinus; A Case Report

Abstract

A true malignant mixed tumor (TMMT), a neoplasm in which both epithelial and non-epithelial components of pleomorphic adenoma show malignancy, is very rare. We treated an extraordinarily rare case of TMMT of maxillary sinus origin.
A 65-year-old woman visited our clinic having a one-month history of left cheek pain. The CT scan suggested a benign or low-grade-malignant tumor of the left maxillary sinus. Probe maxillotomy was performed, and its macroscopic findings were a soft, whitish tumor. The histological diagnosis was “malignant mixed tumor”, the epithelial component of which was adenocarcinoma, and the non-epithelial component of which was fibrosarcoma. There was no cervical or distant metastasis.
Combination therapy for maxillary squamous cell carcinoma, consisting of irradiation, chemotherapy and necrotomy, was performed. After 60 Gy of irradiation, since no malignant cells were found in the abraded tissue from the sinus, the patient was discharged.
The patient has shown no evidence of recurrence as of 3 months after the irradiation therapy.