CHONDROMYXOID FIBROMA OF THE SKULL BASE - A TUMOR WHICH MAY BE CONFUSED WITH CHORDOMA AND CHONDROSARCOMA - A REPORT OF 3 CASES AND REVIEW OF THE LITERATURE

Three cases of chondromyxoid fibroma arising in the skull base are rep orted. The tumors arose in females 34, 65, and 66 (median 55) years of age. Two women presented with headaches, and one with nasal obstructi on. Radiographic studies revealed that all three lesions were expansil e soft tissue masses centered in the clivus, at least 4 cm in greatest diameter. One lesion involved primarily the clivus, the others extend ed from the clivus into the sphenoid and ethmoid sinuses. Two of the t hree cases were initially misdiagnosed as chordoma or chondrosarcoma. The initial treatment was curettage of gross disease in all three case s. One patient also received radiation therapy. One patient had local progression of disease, which was treated with surgery and radiation t herapy. All patients are clinically free of disease 11 to 26 months fo llowing the most recent treatment. Chondromyxoid fibroma can and shoul d be distinguished from chondrosarcoma and chordoma, two tumors which more commonly arise in the skull base and which have the potential to metastasize.