Is preoperative embolization a prerequisite for spinal metastases surgical management?

Background: Preoperative embolization decreases the intraoperative risk of hemorrhage in spinal decompression surgery of hypervascular metastases such as renal cell carcinoma. There is no consensus concerning embolization in other metastases. The purpose of this study was to compare the intraoperative amount of blood loss in embolized versus non-embolized patients, seeking for differences depending on the primary tumor and the extent of surgery. Patients and methods: Ninety-three patients, average age 60.5 years, were operated. The origins of metastases were: 28 breast cancer (30.1%), 19 pulmonary carcinoma (20.4%), 16 renal cell carcinoma (17.2%), 30 other cancers (32.3%). Surgical procedures were: 52 thoracolumbar laminectomies with instrumentation, 29 thoracolumbar corpectomies or vertebrectomies, 12 cervical corpectomies. A preoperative microsphere embolization was performed in 35 patients. Blood loss was evaluated by: blood volume in surgical aspiration devices, number of transfused packed red blood cells units and hemoglobin variation during surgery. Results: Renal metastases were systematically embolized. In the breast group, there was no significant difference (P > 0.05) in blood loss between embolization versus non-embolization. In the pulmonary group and in other metastases, no difference was found either. The extent of surgery (corpectomy/vertebrectomy versus thoracolumbar instrumentation and cervical corpectomy) increased bleeding: breast 1775 ml versus 778 ml and 600 ml respectively (P = 0.048), pulmonary 2500 ml versus 430 ml and 180 ml (P = 0.020), renal 3346 ml versus 1175 ml and 780 ml (P = 0.036) and others 1550 ml versus 474 ml and 400 ml (P = 0.020). Conclusions: Embolization decreases the risk of hemorrhage in highly vascularized metastases such as renal cell carcinoma. A benefit of embolization was not found for metastases of breast or pulmonary tumors. As far as other metastases, thyroid carcinoma should be analyzed on a greater cohort. The extent of surgery remains an important risk factor for intraoperative bleeding. A preoperative angiogram should be carried out in all types of metastases prior to a thoracolumbar corpectomy or vertebrectomy to perform an embolization if the tumor is hypervascular. Level of evidence: Level IV, retrospective study. (C) 2012 Elsevier Masson SAS. All rights reserved.