Charles G. Fisher, Tony Goldschlager, Stefano Boriani, Peter Paul Varga, Laurence D. Rhines, Michael G. Fehlings, Alessandro Luzzati, Mark B. Dekutoski, Jeremy J. Reynolds, Dean Chou, Sigurd H. Berven, Richard P. Williams, Nasir A. Quraishi, Chetan Bettegowda, and Ziya L. Gokaslan
The National Institutes of Health recommends strategies to obtain evidence for the treatment of rare conditions such as primary tumors of the spine (PTSs). These tumors have a low incidence and are pathologically heterogeneous, and treatment approaches are diverse. Appropriate evidence-based care is imperative. Failure to follow validated oncological principles may lead to unnecessary mortality and profound morbidity. This paper outlines a scientific model that provides significant evidence guiding the treatment of PTSs.
A four-stage approach was used: 1) planning: data from large-volume centers were reviewed to provide insight; 2) recruitment: centers were enrolled and provided the necessary infrastructure; 3) retrospective stage: existing medical records were reviewed and completed with survival data; and 4) prospective stage: prospective data collection has been implemented. The AOSpine Knowledge Forum Tumor designed six modules: demographic, clinical, diagnostic, therapeutic, local recurrence, survival, and perioperative morbidity data fields and provided funding.
It took 18 months to implement Stages 1–3, while Stage 4 is ongoing. A total of 1495 tumor cases were captured and diagnosed as one of 18 PTS histotypes. In addition, a PTS biobank network has been created to link clinical data with tumor pathology and molecular analysis.
This scientific model has not only aggregated a large amount of PTS data, but has also established an international collaborative network of spine oncology centers. Access to large volumes of data will generate further research to guide and enhance PTS clinical management. This model could be applied to other rare neoplastic conditions. Clinical trial registration no.: NCT01643174 (ClinicalTrials.gov).
Daniel M. Sciubba, Mohamed Macki, Mohamad Bydon, Niccole M. Germscheid, Jean-Paul Wolinsky, Stefano Boriani, Chetan Bettegowda, Dean Chou, Alessandro Luzzati, Jeremy J. Reynolds, Zsolt Szövérfi, Patti Zadnik, Laurence D. Rhines, Ziya L. Gokaslan, Charles G. Fisher, and Peter Paul Varga
Clinical outcomes in patients with primary spinal osteochondromas are limited to small series and sporadic case reports. The authors present data on the first long-term investigation of spinal osteochondroma cases.
An international, multicenter ambispective study on primary spinal osteochondroma was performed. Patients were included if they were diagnosed with an osteochondroma of the spine and received surgical treatment between October 1996 and June 2012 with at least 1 follow-up. Perioperative prognostic variables, including patient age, tumor size, spinal level, and resection, were analyzed in reference to long-term local recurrence and survival. Tumor resections were compared using Enneking appropriate (EA) or Enneking inappropriate surgical margins.
Osteochondromas were diagnosed in 27 patients at an average age of 37 years. Twenty-two lesions were found in the mobile spine (cervical, thoracic, or lumbar) and 5 in the fixed spine (sacrum). Twenty-three cases (88%) were benign tumors (Enneking tumor Stages 1–3), whereas 3 (12%) exhibited malignant changes (Enneking tumor Stages IA–IIB). Sixteen patients (62%) underwent en bloc treatment—that is, wide or marginal resection—and 10 (38%) underwent intralesional resection. Twenty-four operations (92%) followed EA margins. No one received adjuvant therapy. Two patients (8%) experienced recurrences: one in the fixed spine and one in the mobile spine. Both recurrences occurred in latent Stage 1 tumors following en bloc resection. No osteochondroma-related deaths were observed.
In the present study, most patients underwent en bloc resection and were treated as EA cases. Both recurrences occurred in the Stage 1 tumor cohort. Therefore, although benign in character, osteochondromas still require careful management and thorough follow-up.
Ziya L. Gokaslan, Patricia L. Zadnik, Daniel M. Sciubba, Niccole Germscheid, C. Rory Goodwin, Jean-Paul Wolinsky, Chetan Bettegowda, Mari L. Groves, Alessandro Luzzati, Laurence D. Rhines, Charles G. Fisher, Peter Pal Varga, Mark B. Dekutoski, Michelle J. Clarke, Michael G. Fehlings, Nasir A. Quraishi, Dean Chou, Jeremy J. Reynolds, Richard P. Williams, Norio Kawahara, and Stefano Boriani
A chordoma is an indolent primary spinal tumor that has devastating effects on the patient's life. These lesions are chemoresistant, resistant to conventional radiotherapy, and moderately sensitive to proton therapy; however, en bloc resection remains the preferred treatment for optimizing patient outcomes. While multiple small and largely retrospective studies have investigated the outcomes following en bloc resection of chordomas in the sacrum, there have been few large-scale studies on patients with chordomas of the mobile spine. The goal of this study was to review the outcomes of surgically treated patients with mobile spine chordomas at multiple international centers with respect to local recurrence and survival. This multiinstitutional retrospective study collected data between 1988 and 2012 about prognosis-predicting factors, including various clinical characteristics and surgical techniques for mobile spine chordoma. Tumors were classified according to the Enneking principles and analyzed in 2 treatment cohorts: Enneking-appropriate (EA) and Enneking-inappropriate (EI) cohorts. Patients were categorized as EA when the final pathological assessment of the margin matched the Enneking recommendation; otherwise, they were categorized as EI.
Descriptive statistics were used to summarize the data (Student t-test, chi-square, and Fisher exact tests). Recurrence and survival data were analyzed using Kaplan-Meier survival curves, log-rank tests, and multivariate Cox proportional hazard modeling.
A total of 166 patients (55 female and 111 male patients) with mobile spine chordoma were included. The median patient follow-up was 2.6 years (range 1 day to 22.5 years). Fifty-eight (41%) patients were EA and 84 (59%) patients were EI. The type of biopsy (p < 0.001), spinal location (p = 0.018), and if the patient received adjuvant therapy (p < 0.001) were significantly different between the 2 cohorts. Overall, 58 (35%) patients developed local recurrence and 57 (34%) patients died. Median survival was 7.0 years postoperative: 8.4 years postoperative for EA patients and 6.4 years postoperative for EI patients (p = 0.023). The multivariate analysis showed that the EI cohort was significantly associated with an increased risk of local recurrence in comparison with the EA cohort (HR 7.02; 95% CI 2.96–16.6; p < 0.001), although no significant difference in survival was observed.
EA resection plays a major role in decreasing the risk for local recurrence in patients with chordoma of the mobile spine.
Charlotte Dandurand, Charles G. Fisher, Laurence D. Rhines, Stefano Boriani, Raphaële Charest-Morin, Alessandro Gasbarrini, Alessandro Luzzati, Jeremy J. Reynolds, Feng Wei, Ziya L. Gokaslan, Chetan Bettegowda, Daniel M. Sciubba, Aron Lazary, Norio Kawahara, Michelle J. Clarke, Y. Raja Rampersaud, Alexander C. Disch, Dean Chou, John H. Shin, Francis J. Hornicek, IIya Laufer, Arjun Sahgal, and Nicolas Dea
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.
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.
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.
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.