Intraoperative radiation therapy for metastatic spinal tumors

Study Design. Retrospective examination of 37 pa tients with metastatic spi nal tumors treated with intraoperative radiation therapy. Objective. To propose a new technique for local control of metastatic spina l tumors. Summary of Background Data. No reports of intraoperative radiation therapy for metastatic spinal tumors have been published as of the time of this wri ting. Methods. Between December 1992 and April 1996, intraoperative radiation the rapy was performed in 37 patients with spinal metastasis. In all but one pa tient, the spinal cord was protected during intraoperative radiation therap y by a lead shield to prevent radiation myelopathy. In addition to intraope rative radiation therapy, 22 of the 37 patients received external radiation therapy, either before or after their operation. Although the authors had recommended a dose of approximately 30 Gy of external radiation therapy aft er wound suture removal to patients who did not receive preoperative radiat ion therapy, the remaining 15 patients did not receive external radiation t herapy, either by choice or because they received alternative therapy. Adju vant chemotherapy for various cancers was administered to 9 of the 37 patie nts, including 4 of the aforementioned 15. Results. All patients attained clinical improvement in pain, neurologic fun ction status, or both, with no evidence of local recurrence. Radiation myel opathy developed in the one patient whose spinal cord was not protected dur ing intraoperative radiation therapy. Eleven patients experienced metastasi s in vertebrae that were not surgically treated. Conclusion. Intraoperative radiation therapy appears to achieve good pallia tion and may be useful for local control of spinal metastases.