Perioperative Complications of Total En Bloc Spondylectomy: Adverse Effects of Preoperative Irradiation

Abstract

BackgroundTotal en bloc spondylectomy (TES) is associated with a high complication rate because it is technically demanding and involves patients compromised by cancer. Specifically, perioperative complications are more likely to occur in patients receiving preoperative irradiation. We examined the perioperative complications associated with TES in patients receiving preoperative irradiation.MethodsSeventy-seven patients underwent TES between May 2010 and April 2013. We performed a retrospective review of prospectively collected data for 50 patients with metastatic tumors of the thoracic spine, excluding patients with primary spinal tumors, lumbar spinal metastasis, and combined anterior and posterior approach TES. Patients were divided into 2 groups: those with preoperative irradiation (RT-TES group, 18 patients) and those without preoperative irradiation (TES group, 32 patients). The following perioperative complications, occurring within 2 months of surgery, were compared between the groups: intraoperative dural injuries, epidural hematomas, deep surgical-site infections, postoperative cerebrospinal fluid leakage, wound dehiscence, pleural effusions, and neurological deficits.ResultsSignificant differences in patient characteristics were not observed between the RT-TES and TES groups. Perioperative TES complications occurred in 20/50 patients (40.0%). The complication rate in the RT-TES group was 77.8% (14 out of 18), threefold higher than the 18.8% (6 out of 32) in the TES group (P<0.01). The incidence of complications, including intraoperative dural injuries, postoperative cerebrospinal fluid leakage, wound dehiscence, and pleural effusions, was significantly higher in the RT-TES group (P<0.01).ConclusionThe perioperative complication rate associated with TES for spinal metastasis was significantly higher among patients receiving preoperative irradiation than among those not receiving preoperative irradiation.

Loss of Local Tumor Control After Index Surgery for Spinal Metastases: A Prospective Cohort Study

“…27 In another study from the group of Tomita, 10 patients with spinal metastases for which en bloc spondylectomy was performed, had no recurrences after 10 years of follow up. 28 Complication rates for en bloc spondylectomy vary widely 14,24,29,30 and partially depends on surgeons' caseload and expertise. Whether more radical surgical removal of metastatic spinal lesions affects survival is unclear; a different question is whether en bloc resection might lower the rate of LLC.…”

“…While it is thought that radical en bloc resections may reduce the incidence of loss of local control, 9 such interventions are associated with higher surgical risks. 14 The reported incidence of loss of local control after piecemeal intralesional debulking varies between 1.4 and 32% depending on the definition used for loss of local control: 32% for radiological loss of local control, 15 20-22% for symptomatic loss of local control 16,17 and 1.4-8.4% for patients effectively undergoing revision surgery. 18,19 Laufer et al reported a median survival of 9 months after repeat surgery for recurrent spinal metastasis, and a 65% rate of preserved ambulation.…”

Effects of Radiation on Spinal Dura Mater and Surrounding Tissue in Mice

“…In clinical studies at our facility, occurrence of intraoperative dural injury was significantly higher at ≥12 months postirradiation than at <12 months [ 12 ]. In these cases, epidural fibrosis, as a late-stage radiation injury, could be a major cause of the subsequent dural injury.…”

“…Therefore, it is anticipated that meningeal permeability would be increased in association with postirradiation ABC thinning by a similar mechanism. Clinically, postoperative CSF leakage is sometimes experienced despite the absence of dural injury [ 12 ]; the possibility that this would be caused by an increase in meningeal permeability due to radiation injury is fully conceivable. In the future, analysis of more samples and experimental verification of increased meningeal permeability associated with ABC thinning is necessary.…”

“…However, late-stage radiation injury is associated with perioperative complications, such as delayed wound healing or wound infection [ 10 , 11 ]. In addition, research at our facility has indicated that dural injury and postoperative cerebrospinal fluid (CSF) leakage, probably due to adhesion around the dura mater, are frequently observed during surgery for spinal tumors after radiotherapy [ 12 ]. Therefore, similar to radiation-induced fibrosis—a major late-stage radiation injury in other tissue [ 13 – 15 ]—epidural fibrosis is anticipated to precede dural injury in the spine; however, this has not yet been investigated.…”