Dea, Nicolas

OBJECTIVE Intramedullary spinal cord tumors (IMSCTs) are rare tumors with heterogeneous presentations and natural histories that complicate their management. Standardized guidelines are lacking on when to surgically intervene and the appropriate aggressiveness of resection, especially given the risk of new neurological deficits following resection of infiltrative tumors. Here, the authors present the results of a modified Delphi method using input from surgeons experienced with IMSCT removal to construct a framework for the operative management of IMSCTs based on the clinical, radiographic, and tumor-specific characteristics. METHODS A modified Delphi technique was conducted using a group of 14 neurosurgeons experienced in IMSCT resection. Three rounds of written correspondence, surveys, and videoconferencing were carried out. Participants were queried about clinical and radiographic criteria used to determine operative candidacy and guide decision-making. Members then completed a final survey indicating their choice of observation or surgery, choice of resection strategy, and decision to perform duraplasty, in response to a set of patient- and tumor-specific characteristics. Consensus was defined as ≥ 80% agreement, while responses with 70%–79% agreement were defined as agreement. RESULTS Thirty-six total characteristics were assessed. There was consensus favoring surgical intervention for patients with new-onset myelopathy (86% agreement), chronic myelopathy (86%), or progression from mild to disabling numbness (86%), but disagreement for patients with mild numbness or chronic paraplegia. Age was not a determinant of operative candidacy except among frail patients, who were deemed more suitable for observation (93%). Well-circumscribed (93%) or posteriorly located tumors reaching the surface (86%) were consensus surgical lesions, and participants agreed that the presence of syringomyelia (71%) and peritumoral T2 signal change (79%) were favorable indications for surgery. There was consensus that complete loss of transcranial motor evoked potentials with a 50% decrease in the D-wave amplitude should halt further resection (93%). Preoperative symptoms seldom influenced choice of resection strategy, while a distinct cleavage plane (100%) or visible tumor-cord margins (100%) strongly favored gross-total resection. CONCLUSIONS The authors present a modified Delphi technique highlighting areas of consensus and agreement regarding surgical management of IMSCTs. Although not intended as a substitute for individual clinical decision-making, the results can help guide care of these patients. Additionally, areas of controversy meriting further investigation are highlighted.

OBJECTIVE Oncological resection of primary spine tumors is associated with lower recurrence rates. However, even in the most experienced hands, the execution of a meticulously drafted plan sometimes fails. The objectives of this study were to determine how successful surgical teams are at achieving planned surgical margins and how successful surgeons are in intraoperatively assessing tumor margins. The secondary objective was to identify factors associated with successful execution of planned resection. METHODS The Primary Tumor Research and Outcomes Network (PTRON) is a multicenter international prospective registry for the management of primary tumors of the spine. Using this registry, the authors compared 1) the planned surgical margin and 2) the intraoperative assessment of the margin by the surgeon with the postoperative assessment of the margin by the pathologist. Univariate analysis was used to assess whether factors such as histology, size, location, previous radiotherapy, and revision surgery were associated with successful execution of the planned margins. RESULTS Three hundred patients were included. The surgical plan was successfully achieved in 224 (74.7%) patients. The surgeon correctly assessed the intraoperative margins, as reported in the final assessment by the pathologist, in 239 (79.7%) patients. On univariate analysis, no factor had a statistically significant influence on successful achievement of planned margins. CONCLUSIONS In high-volume cancer centers around the world, planned surgical margins can be achieved in approximately 75% of cases. The morbidity of the proposed intervention must be balanced with the expected success rate in order to optimize patient management and surgical decision-making.

Abstract BACKGROUND Despite our inability to accurately predict survival in many cancer patients, a life expectancy of at least 3 mo is historically necessary to be considered for surgical treatment of spinal metastases. OBJECTIVE To compare health-related quality of life (HRQOL) in patients surviving <3 mo after surgical treatment to patients surviving >3 mo to assess the validity of this inclusion criteria. METHODS Patients who underwent surgery for spinal metastases between August 2013 and May 2017 were retrospectively identified from an international cohort study. HRQOL was evaluated using generic and disease-specific outcome tools at baseline and at 6 and 12 wk postsurgery. The primary outcome was the HRQOL at 6 wk post-treatment measured by the Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ). RESULTS A total of 253 patients were included: 40 patients died within the first 3 mo after surgery and 213 patients survived more than 3 mo. Patients surviving <3 mo after surgery presented with lower baseline performance status. Adjusted analyses for baseline performance status did not reveal a significant difference in HRQOL between both groups at 6 wk post-treatment. No significant difference in patient satisfaction at 6 wk with regard to their treatment could be detected between both groups. CONCLUSION When controlled for baseline performance status, quality of life 6 wk after surgery for spinal metastasis is independent of survival. To optimize improvement in HRQOL for this patient population, baseline performance status should take priority over expected survival in the surgical decision-making process.

Introduction Primary tumors of the spine requiring enbloc resection are rare. Most published reports are small and focus on disease free survival and recurrence rates. Very few studies focus on the various anterior and posterior reconstructive options and subsequent outcomes with respect to fusion rates and need for revision due to hardware failure. The objective of this review was to (1) summarize the published literature and (2) report the failure rates of various anterior and posterior reconstructive techniques after enbloc resection of spinal tumors and (3) supplement the deficiencies in the available published literature with expert opinion for reconstructive options from a group of experienced international spine tumor surgeons. Material and Methods An electronic search of the literature was undertaken from January 1990 – December 2013 evaluating specific reconstructive techniques of the spine after primary tumor enbloc resection. Prospective/retrospective trials and case series were included in the final analysis when fusion rates or failure rates were reported. The data available for each reconstructive technique was then combined and construct survivorship was summarized. In addition, a questionnaire was administered to a group of 20 international spine tumor surgeons evaluating specific reconstructive preferences at different regions of the spine based on the number of vertebrae resected and whether post-operative radiation was planned. Results The initial search yielded 381 articles with 31 subsequently included for full text review. Fourteen articles were included in the final analysis. There were 146 patients included for final review. There were 2/9 (22%) patients revised from short to long segment constructs and 3 reports of broken pedicle screws with only one requiring revision in longer constructs. Rates of revision for anterior reconstruction were similar for autogenous strut grafts (10%), cages (7.7%) and allograft strut grafts (8.3%). No surgeons responding to the questionnaire recommended short segment posterior constructs. For anterior reconstruction, cages packed with morcellized allograft and autograft were preferred (75%, p < 0.05) while strut bone grafting was choosen more often at the cervicothoracic junction (65%, p < 0.05) and when more than one vertebrae was resected in the mid thoracic spine (75%, p < 0.05). Few surgeons changed their anterior reconstructive technique (15%) or posterior reconstructive technique (10%) when post-operative radiation was planned. Conclusion The literature and consensus opinion supports posterior reconstruction with at least two vertebral levels of support above and below. For anterior vertebral column reconstruction, structural allograft, autograft and cages packed with morcelized bone have shown similar rates of fusion and failure. Expert opinion, however, suggests that structural autograft or potentially vascularized strut grafts should be used when spanning a defect greater than 2 vertebral bodies especially at the cervicothoracic junction.