Purpose:
To evaluate the correlation between the gross imaging evidence of an aggressive masticator space (ms) tumor and the presence of such a ms malignancy.
Materials and methods:
Thirty patients were identified retrospectively who had a malignancy that either arose in or metastasized to the ms, had pathologic verification of the diagnosis, and had magnetic resonance (mr) and/or computed tomographic (ct) images. specifically evaluated was the presence or absence of gross imaging evidence of mandibular erosion and the integrity of the medial ms fascia as evaluated by a smooth margin between this fascia and the parapharyngeal space fat.
Results:
Of the 30 tumors, 28 were high-grade malignancies and 2 were histiocytoses. of these, 5 had mandibular erosion and violation of the ms fascia, 19 had bone erosion with an intact fascia, 4 had neither bone erosion nor fascial violation (3 of these patients were under the age of 20 years), and 2 had fascial violation with no bone erosion.
Conclusions:
In 76.7% of patients with a malignancy arising in the ms, on imaging the medial ms fascia was grossly intact. there were 4 patients with ms malignancy and neither violation of the medial ms fascia nor mandibular bone erosion. thus, these imaging findings may not be good criteria to evaluate the presence of a high-grade ms malignancy, especially if the patient is under the age of 20 years, in which age group ms sarcomas are more likely to arise.