Iatrogenic aortic injuries are a potentially devastating complication of spine surgery. In instrumented cases, injuries may occur in the perioperative period due to iatrogenic vessel injury, or they may occur years later as prominent implants erode or penetrate major vessels. The authors present a case of a 71-year-old man in whom a thoracic pedicle screw was found perforating the thoracic aorta during routine follow-up 6 months after surgery. Due to the risk of future complications, the screw was removed while simultaneously delivering an endovascular aortic stent to gain vascular control. Surgical considerations and potential technical limitations are discussed.
Michelle J. Clarke, James Guzzo, Jean-Paul Wolinsky, Ziya Gokaslan and James H. Black III
Michelle J. Clarke, Patricia L. Zadnik, Mari L. Groves, Daniel M. Sciubba, Timothy F. Witham, Ali Bydon, Ziya L. Gokaslan and Jean-Paul Wolinsky
Recently, aggressive surgical techniques and a push toward en bloc resections of certain tumors have resulted in a need for creative spinal column reconstruction. Iatrogenic instability following these resections requires a thoughtful approach to adequately transfer load-bearing forces from the skull and upper cervical spine to the subaxial spine.
The authors present a series of 7 cases in which lateral mass reconstruction with a cage or fibular strut graft was used to provide load-bearing support, including 1 case of bilateral cage placement.
The authors discuss the surgical nuances of en bloc resection of high cervical tumors and explain their technique for lateral mass cage placement. Additionally, they provide their rationale for the use of these constructs throughout the craniocervical junction and subaxial spine.
Lateral mass reconstruction provides a potential alternative or adjuvant method of restoring the load-bearing capabilities of the cervical spine.
C. Rory Goodwin, Eric W. Sankey, Ann Liu, Benjamin D. Elder, Thomas Kosztowski, Sheng-Fu L. Lo, Charles G. Fisher, Michelle J. Clarke, Ziya L. Gokaslan and Daniel M. Sciubba
Surgical procedures and/or adjuvant therapies are effective modalities for the treatment of symptomatic spinal metastases. However, clinical results specific to the skin cancer spinal metastasis cohort are generally lacking. The purpose of this study was to systematically review the literature for treatments, clinical outcomes, and survival following the diagnosis of a skin cancer spinal metastasis and evaluate prognostic factors in the context of spinal skin cancer metastases stratified by tumor subtype.
The authors performed a literature review using PubMed, Embase, CINAHL, and Web of Science to identify articles since 1950 that reported survival, clinical outcomes, and/or prognostic factors for the skin cancer patient population with spinal metastases. The methodological quality of reviews was assessed using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) tool.
Sixty-five studies met the preset criteria and were included in the analysis. Of these studies, a total of 25, 40, 25, and 12 studies included patients who underwent some form of surgery, radiotherapy, chemotherapy, or observation alone, respectively. Sixty-three of the 65 included studies were retrospective in nature (Class of Evidence [CoE] IV), and the 2 prospective studies were CoE II. Based on the studies analyzed, the median overall survival for a patient with a spinal metastasis from a primary skin malignancy is 4.0 months; survival by tumor subtype is 12.5 months for patients with basal cell carcinoma (BCC), 4.0 months for those with melanoma, 4.0 months for those with squamous cell carcinoma, 3.0 months for those with pilomatrix carcinoma, and 1.5 months for those with Merkel cell carcinoma (p < 0.0001). The overall percentage of known continued disease progression after spine metastasis diagnosis was 40.1% (n = 244/608, range 25.0%–88.9%), the rate of known recurrence of the primary skin cancer lesion was 3.5% (n = 21/608, range 0.2%–100.0%), and the rate of known spine metastasis recurrence despite treatment for all skin malignancies was 2.8% (n = 17/608, range 0.0%–33.3%). Age greater than 65 years, sacral spinal involvement, presence of a neurological deficit, and nonambulatory status were associated with decreased survival in patients diagnosed with a primary skin cancer spinal metastasis. All other clinical or prognostic parameters were of low or insufficient strength.
Patients diagnosed with a primary skin cancer metastasis to the spine have poor overall survival with the exception of those with BCC. The median duration of survival for patients who received surgical intervention alone, medical management (chemotherapy and/or radiation) alone, or the combination of therapies was similar across interventions. Age, spinal region, and neurological status may be associated with poor survival following surgery.
Michelle J. Clarke, Patricia L. Zadnik, Mari L. Groves, Hormuzdiyar H. Dasenbrock, Daniel M. Sciubba, Wesley Hsu, Timothy F. Witham, Ali Bydon, Ziya L. Gokaslan and Jean-Paul Wolinsky
Traditionally, hemisacrectomy and internal hemipelvectomy procedures have required both an anterior and a posterior approach. A posterior-only approach has the potential to complete an en bloc tumor resection and spinopelvic reconstruction while reducing surgical morbidity.
The authors describe 3 cases in which en bloc resection of the hemisacrum and ilium and subsequent lumbopelvic and pelvic ring reconstruction were performed from a posterior-only approach. Two more traditional anterior and posterior staged procedures are also included for comparison.
In all 3 cases, an oncologically appropriate surgery and spinopelvic reconstruction were performed through a posterior-only approach.
The advantage of a midline posterior approach is the ability to perform a lumbosacral reconstruction, necessary in cases in which the S-1 body is iatrogenically disrupted during tumor resection.
Mohammed Abdulaziz, Grant W. Mallory, Mohamad Bydon, Rafael De la Garza Ramos, Jason A. Ellis, Nadia N. Laack, W. Richard Marsh, William E. Krauss, George Jallo, Ziya L. Gokaslan and Michelle J. Clarke
While extent of resection has been shown to correlate with outcomes after myxopapillary ependymoma (MPE) resection, the effect of capsular violation has not been well studied. The role of adjuvant radiation also remains controversial. In this paper the authors' goals were to evaluate outcomes following resection of MPE based on intraoperative capsular violation and to explore the role of adjuvant radiotherapy in cases of capsular violation.
A retrospective review of patients undergoing resection of MPE at 2 academic institutions between 1990 and 2013 was performed. Cases with dissemination at presentation, less than 12 months of follow-up, or incomplete records were excluded. Extent of resection was defined as en bloc if all visible tumor was removed without capsular violation, gross-total resection (GTR) if all visible tumor was removed, but with capsular violation, and subtotal resection (STR) if a known residual was left at the time of surgery. Postoperative MR images were reviewed to confirm the extent of resection. Primary outcomes were progression-free survival (PFS) and overall recurrence rates. The effects of extent of resection, capsular violation, and adjuvant radiotherapy on recurrence rates and PFS were analyzed using Kaplan-Meier statistics. Associations between recurrence and preoperative variables were evaluated using Fisher exact methods and t-tests where appropriate.
Of the 107 patients reviewed, 58 patients (53% were male) met inclusion criteria. The mean age at surgery was 40.8 years (range 7–68 years). The median follow-up was 51.5 months (range 12–243 months). Extent of resection was defined as en bloc in 46.5% (n = 27), GTR in 34.5% (n = 20), and STR in 18.9% (n = 11). No recurrences were noted in the en bloc group, compared with 15% (n = 3) and 45% (n = 5) in the GTR and STR groups. En bloc resection was achieved most frequently in tumors involving the conus. Twelve patients (20%) underwent adjuvant radiotherapy following either STR or GTR. The overall recurrence rate was 13.8% (n = 8), and the 5-year PFS was 81%. Capsular violation was associated with a higher recurrence rate (p = 0.005). Adjuvant radiotherapy showed a nonsignificant trend of lower recurrence rates (16.7% vs 31.6%, p = 0.43) and longer PFS at 5 years (83.3% vs 49.9%, p = 0.16) in cases of capsular violation.
A strong correlation between capsular violation and recurrence was found following removal of MPE and should be assessed when defining extent of resection in future studies. Although the use of adjuvant radiotherapy in cases of capsular violation showed a trend toward improved PFS, further investigation is needed to establish its role as salvage therapy also appears to be effective at halting disease progression.
Ganesh M. Shankar, Michelle J. Clarke, Tamir Ailon, Laurence D. Rhines, Shreyaskumar R. Patel, Arjun Sahgal, Ilya Laufer, Dean Chou, Mark H. Bilsky, Daniel M. Sciubba, Michael G. Fehlings, Charles G. Fisher, Ziya L. Gokaslan and John H. Shin
Primary osteosarcoma of the spine is a rare osseous neoplasm. While previously reported retrospective studies have demonstrated that overall patient survival is impacted mostly by en bloc resection and chemotherapy, the continued management of residual disease remains to be elucidated. This systematic review was designed to address the role of revision surgery and multimodal adjuvant therapy in cases in which en bloc excision is not initially achieved.
A systematic literature search spanning the years 1966 to 2015 was performed on PubMed, Medline, EMBASE, and Web of Science to identify reports describing outcomes of patients who underwent biopsy alone, neurological decompression, or intralesional resection for osteosarcoma of the spine. Studies were reviewed qualitatively, and the clinical course of individual patients was aggregated for quantitative meta-analysis.
A total of 16 studies were identified for inclusion in the systematic review, of which 8 case reports were summarized qualitatively. These studies strongly support the role of chemotherapy for overall survival and moderately support adjuvant radiation therapy for local control. The meta-analysis revealed a statistically significant benefit in overall survival for performing revision tumor debulking (p = 0.01) and also for chemotherapy at relapse (p < 0.01). Adjuvant radiation therapy was associated with longer survival, although this did not reach statistical significance (p = 0.06).
While the initial therapeutic goal in the management of osteosarcoma of the spine is neoadjuvant chemotherapy followed by en bloc marginal resection, this objective is not always achievable given anatomical constraints and other limitations at the time of initial clinical presentation. This systematic review supports the continued aggressive use of revision surgery and multimodal adjuvant therapy when possible to improve outcomes in patients who initially undergo subtotal debulking of osteosarcoma. A limitation of this systematic review is that lesions amenable to subsequent resection or tumors inherently more sensitive to adjuvants would exaggerate a therapeutic effect of these interventions when studied in a retrospective fashion.
Mark B. Dekutoski, Michelle J. Clarke, Peter Rose, Alessandro Luzzati, Laurence D. Rhines, Peter P. Varga, Charles G. Fisher, Dean Chou, Michael G. Fehlings, Jeremy J. Reynolds, Richard Williams, Nasir A. Quraishi, Niccole M. Germscheid, Daniel M. Sciubba, Ziya L. Gokaslan, Stefano Boriani and The AOSpine Knowledge Forum Tumor
Primary spinal osteosarcomas are rare and aggressive neoplasms. Poor outcomes can occur, as obtaining marginal margins is technically demanding; further Enneking-appropriate en bloc resection can have significant morbidity. The goal of this study is to identify prognostic variables for local recurrence and mortality in surgically treated patients diagnosed with a primary osteosarcoma of the spine.
A multicenter ambispective database of surgically treated patients with primary spine osteosarcomas was developed by AOSpine Knowledge Forum Tumor. Patient demographic, diagnosis, treatment, perioperative morbidity, local recurrence, and cross-sectional survival data were collected. Tumors were classified in 2 cohorts: Enneking appropriate (EA) and Enneking inappropriate (EI), as defined by pathology margin matching Enneking-recommended surgical margins. Prognostic variables were analyzed in reference to local recurrence and survival.
Between 1987 and 2012, 58 patients (32 female patients) underwent surgical treatment for primary spinal osteosarcoma. Patients were followed for a mean period of 3.5 ± 3.5 years (range 0.5 days to 14.3 years). The median survival for the entire cohort was 6.7 years postoperative. Twenty-four (41%) patients died, and 17 (30%) patients suffered a local recurrence, 10 (59%) of whom died. Twenty-nine (53%) patients underwent EA resection while 26 (47%) patients underwent EI resection with a postoperative median survival of 6.8 and 3.7 years, respectively (p = 0.048). EI patients had a higher rate of local recurrence than EA patients (p = 0.001). Patient age, previous surgery, biopsy type, tumor size, spine level, and chemotherapy timing did not significantly influence recurrence and survival.
Osteosarcoma of the spine presents a significant challenge, and most patients die in spite of aggressive surgery. There is a significant decrease in recurrence and an increase in survival with en bloc resection (EA) when compared with intralesional resection (EI). The effect of adjuvant and neoadjuvant chemotherapeutics, as well as method of biopsy, requires further exploration.
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.