BASE OF SKULL CHORDOMA - A CORRELATIVE STUDY OF HISTOLOGIC AND CLINICAL-FEATURES OF 62 CASES

Background. Chordomas are uncommon primary malignant tumors of bone th at typically occur in the axial skeleton including the sacrum, vertebr ae, and skull base. The base of skull tumors usually are not amenable to complete surgical resection, and most require postoperative radioth erapy. The natural history of skull base chordoma is typified by slow locally invasive tumor progression and eventual death, although few pa rameters are known that allow stratification of patients into prognost ic groups. Methods. Sixty-two patients with skull base chordomas treat ed at the Massachusetts General Hospital by proton beam irradiation th erapy with at least 2 years of follow-up information were reviewed in an attempt to identify clinical and pathologic parameters that predict ed outcome. Results. Female sex, tumor necrosis in preradiation treatm ent biopsy, and tumor volume in excess of 70 ml were each independent predictors of shortened overall survival after radiation therapy for s kull base chordoma. Conclusions. Stratification of patients with skull base chordoma into poor and good outcome groups can be performed usin g the three parameters identified in our study. In addition, the strik ing difference in survival between the sexes suggests that further inv estigations of these tumors should include determination of their horm onal receptor status and consideration of hormonal manipulation in the ir management.