Noriaki Yokogawa (Department of Orthopedic Surgery, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan) and others report in Plos One that the rate of perioperative complications in patients who have undergone total en bloc spondylectomy for the management of metastatic spinal tumours is significantly higher in those who have received preoperative irradiation compared with those who have not received preoperative irradiation.
Yokogawa et al comment that total en bloc spondylectomy is a “technically demanding procedure” and that its use in patients who have complicated medical backgrounds (eg. cancer) was associated with a higher rate of perioperative complications than is associated with other spinal surgeries. They add: “Specifically, perioperative complications are more likely to occur in patients receiving preoperative irradiation.” However, the authors state that the rate of perioperative complications following total en bloc spondylectomy with a focus on the adverse effects of preoperative radiation has not been studied. The aim of their study was to examine the rate of perioperative complications associated with total en bloc spondylectomy in a single-centre retrospective study.
Of 50 patients in the study, all of whom underwent total en bloc spondylectomy for the management of metastatic tumours of the thoracic spine, 18 had received preoperative irradiation and 32 had not. A total of 37 perioperative complications were reported, with 30 occurring in the patients who received preoperative irradiation. Yokogawa et al state: “Thus, the rate of complications in the preoperative irradiation total en bloc spondylectomy group was 77.8% or threefold higher than in the 18.8% observed in the total en bloc spondylectomy group. This difference was statistically significant (p<0.01).” They add that significant differences were observed between groups in the number intraoperative dural injuries, postoperative cerebral spinal fluid leaks, wound dehiscence, and pleural effusions (p<0.01 for the comparisons).
The authors also reviewed potential differences in the rate of perioperative complications between patients who were exposed to ≥40Gy of irradiation and those exposed to <40Gy of irradiation, finding that the rate of wound dehiscence in the ≥40Gy group was 36.4% and 0% in the <40Gy group—but this was not a statistically significant difference. Furthermore, Yokogawa et al found that the rate of intraoperative dural tears was 60% in patients who received irradiation ≥12 months prior to surgery compared with 12.5% in patients who received irradiation <12 months prior to surgery (p=0.041).
Yokogawa et al, on the basis of their study, claim that “careful consideration” should be given to patients receiving preoperative irradiation and “wherever possible”, preoperative irradiation should be avoided in patients having an indication for total en bloc spondylectomy. But, they add that as radiotherapy is a standard treatment for spinal metastases—“making the need for total en bloc spondylectomy inevitable in some patients receiving radiotherapy”—preventative measures to minimise complications need to be established in future study.
Yokogawa told Spinal News International: “The most important thing is to avoid easy irradiation of radio-resistant cancer such as renal cell carcinoma and thyroid cancer.”