STUDY DESIGN: Twenty-one cases of chordoma arising in the mobile spine were retrospectively reviewed. OBJECTIVES: All the cases were submitted to oncologic and surgical staging to correlate treatment and outcome. SUMMARY OF BACKGROUND DATA: Excluding plasmacytomas, chordoma is the most frequent primary malignant tumor of the spine, occurring mainly in elderly men. The course of the disease is slow, metastases occur late, and death can result from complications related to local extension of the disease. Complete excision of the tumor according to oncologic criteria can be hampered by extension of the tumor and by anatomic constraints in the mobile spine. METHODS: All charts, radiographs, and images were reviewed. The composite information provided by this review allowed for oncologic and surgical staging of these cases. Treatment was defined according to Ennekings criteria. All the patients were followed for determination of their status clinically and radiographically. RESULTS: Ten patients died (1 to 137 months after treatment, mean 65 months); four patients are alive with the disease; only seven patients (33%) are symptom free at the final follow-up (39 to 112 months after treatment, mean 65 months). Conventional radiation therapy was not effective in eradicating the tumor, even if associated with palliative or debulking surgery: of 15 cases, 12 were associated with recurrence or progression. Intralesional surgery also was not effective (two recurrences in two cases, 18 to 41 months later). En bloc excision of the lesion, sometimes combined with radiation therapy as an adjuvant, obtained the best results (four patients disease free at 39 to 112 months, mean 77 months). CONCLUSIONS: En bloc excision--even if marginal--is the treatment of choice of chordomas of the spine. Early diagnosis and careful surgical staging and planning are necessary. Megavoltage radiation can be administered as an adjuvant.