[Chondrosarcoma of the skull base associated with fatal intratumoral hemorrhage : report of an autopsy case and review of the literature].

We report a case of intracranial chondrosarcoma of the skull base with fatal intra- and peritumoral hemorrhage. A 75-year-old woman complained of right blepharoptosis and diplopia in 1989. An initial diagnosis of Tolosa-Hunt syndrome was made, and the patient was treated with steroid hormone therapy at a local hospital. Because the symptoms had not been relieved, she was admitted to our hospital. Computed tomography (CT) scan and magnetic resonance (MR) images demonstrated a large mass extending from the right side of the clivus to the parasellar region and petrous apex. The mass was partially calcified and had destroyed the base of the middle cranial fossa. The lesion had homogeneous enhancement with contrast medium. Preoperative diagnosis was chordoma or chondroma. A biopsy of the tumor was made. The pathological diagnosis of biopsy specimen was chondroid chordoma. The patient was followed up but no palliative treatment such as radiotherapy was given. On June 25, 1991, she suffered from cerebral infarction. On June 29, 1993, she died of sudden respiratory failure. Autopsy was performed. It revealed intra- and peritumoral hematoma compressing the medulla oblongata, pons and midbrain. Histologically immature chondroid cells proliferated in a myxoid-rich extracellular matrix. The tumor cells were composed of hyperchromatic nuclei and eosinophilic cytoplasm, but there was no evidence of notochordal differentiation. Compared with biopsy findings, the tumor showed high cellular density. Immunohistochemically, the tumor cells reacted positively for S - 100 protein, vimentin and cytokeratin, but negatively for epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA). In view of these histopathological findings, the diagnosis of low-grade myxoid chondrosarcoma was established. Intratumoral hemorrhage often occurs in malignant brain tumors such as glioblastoma and metastatic brain tumor, but chondroid tumors rarely develop a fatal type of intratumoral hemorrhage. Only 8 cases have been reported in detail to date. We discuss the immunohistochemical features and spontaneous intratumoral hemorrhage of chondrosarcoma.