A system for surgical staging and management of spine tumors: A clinical outcome study of giant cell tumors of the spine

Study Design. This study developed and independently applied a spine tumor classification system, referred to as the Weinstein-Boriani-Biagini system, in a retrospective analysis of a series of patients with spinal giant cell tumors from three institutions. Objective. To evaluate factors of potential prognostic significance for recurrence of spinal giant cell tumors. Summary of Background Data. No prior reviews of patients treated with modern surgical techniques are available. Methods. Charts and radiographs for 36 cases of spinal giant cell tumors were reviewed by an independent investigator. All patients had had recent clinical follow-up examinations. All patients were classified according to the Enneking system. A subgroup of 24 patients for whom preoperative computed tomography scans were available were classified using the Weinstein-Boriani-Biagini staging system. Outcome measures included pain, neurologic status, and tumor recurrence. Results. Recurrence rates were substantially higher among patients treated with attempted surgical excision before referral to a tertiary care center (83% vs. 18%). There was a higher recurrence rate for tumors that involved the vertebral body and posterior elements in comparison with lesions residing in only anterior elements (24% vs. 0%). Tumors that had extra-osseous extension into the canal and into the paraspinous musculature had a higher recurrence rate than tumors either confined to the osseous compartment or with extension either into the spinal canal or externally into paraspinous planes, but not both (21% vs. 10%). Conclusions. These results indicate that the Weinstein- Boriani-Biagini system may prove useful in developing treatment algorithms and in assessing outcome for these rare and difficult lesions. At least in the case of giant cell tumors, the musculoskeletal tumor staging system as developed by Enneking for long bones suggests the ideal surgical margin and may provide information relevant to tumor recurrence rates. Additional aspects of tumor extent and location, however, may berelevant to primary tumor recurrence rates when the selesions occur in the spine.