EN-BLOC RESECTIONS OF BONE-TUMORS OF THE THORACOLUMBAR SPINE - A PRELIMINARY-REPORT ON 29 PATIENTS

Study Design. Twenty-nine patients with primary bone tumors and solita ry metastases of the thoracolumbar spine treated with en bloc resectio n are reviewed retrospectively. Objective. To demonstrate the possibil ity to apply in the spine the same principles of surgical oncology ado pted for primary bone tumors of the limbs. Summary of Background Data. The surgical oncologic staging systems currently applied in limb tumo r surgery are difficult to apply to spinal tumors. The anatomic condit ions make extralesional surgery difficult or impossible, which has res trained a more common use of resection surgery in the spine. Focus is put on a new surgical staging system and en bloc vertebral resection. Methods. Twenty-five primary malignant and aggressive benign bone tumo rs and four solitary metastases were treated. The patients were submit ted to oncologic and surgical staging for surgical planning. The prima ry tumors were classified according to Enneking system: three Stage IA , sic Stage IB, eight Stage IIB, eight Stage 3 benign. Staging accordi ng to the Weinstein-Boriani-Biagini system was also done. Thirteen les ions involved the vertebral body; nine lesions developed in the poster ior arch, or part of it, and seven lesions occupied part of the body a nd part of the arch. A careful anesthesiologic evaluation was performe d as well a a continuous intraoperative on-line monitoring of the vita l parameters. The en bloc resections (multisegmental in five patients) were performed in 10 thoracic, in 16 lumbosacral lesion. Reconstructi on was performed, aiming to replace the resected columns. The specimen s were submitted to histologic study of the margins. All the patients were followed, and their status was defined on clinical and imaging st udies. Results. In 20 patients, a wide margin was achieved, in eight a marginal margin, in one an intralesional margin. The margin was conta minated in seven patients. Surgical time was 3-21 hours (average, 12 h ours). No patient died during surgery or from surgical complications. Three mechanical failures of the implants required additional surgery. One deep infection arose. The only neurologic problems observed were related to the nerve roots sectioned for oncologic purpose. No local r ecurrence was found at follow-up evaluation after 6-134 months (averag e, 30 months). Conclusions. En bloc resection can be performed in sele cted tumors of the spine; the indication to such major surgery must be based on the oncologic stage, and the procedure must be carefully pla nned. For this purpose, the Weinstein-Boriani-Biagini system could be a helpful tool. Long-term results must be weighted before a definitive statement of the indications can be made.