[Clinical and pathological study of chordoma in the skull base]

To study the clinical and pathological characteristics of chordoma in the skull base.

The clinical manifestation, radiological finding and pathological characteristics in 20 patients with skull base chordoma were reviewed. Among them, 7 were immunohistochemical stained for keratin, epithelial membrane antigen, vimentin, glial fibrillary acidic protein and desmen, 2 were studied by electron microscope. 19 patients received surgical resection(5 cases were assisted by nasal endoscope). Eleven patients received radiation therapy. All 19 patients were followed-up for 3-5 years after treatment.

(1) Clinical type were divided into four types in this group according to symptoms, sign, imaging features, operation finding, the original places and the expansive direction of the tumor. Seller type 5 cases, clival type 9 cases, occipito-temproral type 2 cases and extent type 4 cases. One case with multiple cranial never palsies died due to the pressure on brain stem by the neoplasm, was autopsied prove lungs metastasis. 5 years survival rates were 65% and 35% respectively. (2) Vacuolated physaliferous cell is the pathology characteristic of chordoma. (3) Positive rate of epithelial marker antigens are higher than other mesenchymal neoplasms. Distended rough endoplasmic reticulum and filament were found within the cytoplasm under transmission electron microscope.

Chordoma is a kind of low malignancy which express epithelial and mesenchymal characteristics. Vacuolated physaliferous cell is the characteristic Pathologic appearance. Immunohistiochemical stain is helpful in differential diagnosis. Complete excision is still technically impossible. Chordoma maintain high recurrence rate after surgery, with metastasis. Combined modality therapy include surgical operation and radiation could prolonged survival period.