Faculty Bibliography

OPINION STATEMENT/UNASSIGNED:The management of recurrent chordomas are clinically challenging because of its relentless nature. Local therapy, whether surgery or radiation, are important considerations since local progression of disease results in significant morbidity and locally aggressive treatment is often required. Stereotactic radiosurgery, shown to be very effective for radioresistant histologies, may be an important radiotherapeutic approach for recurrent tumors. Ultimately, the treatment of recurrent chordoma is palliative in intent, thus, enthusiasm for improving local control must be tempered against the possible impact of treatment on quality of life. Judicious use of radiotherapy and surgery can often provide meaningful palliation and local control of recurrences. Systemic treatment options, particularly with targeted molecules have great potential for chordomas in the recurrent setting, as the risk of disseminated disease is higher. The development of tools to help assess potential targets for drug therapy will be crucial. The incorporation of locally aggressive therapy and effective systemic therapy will be critical for the successful management of recurrent chordomas. At present, there is a paucity of published data regarding salvage therapy. Nonetheless, advances in surgical, medical, and radiation oncology are providing new avenues of research and potentially may have significant impact upon successful salvage treatment.

BACKGROUND:Treatment of spinal and intracranial tumors with dural involvement is complicated by radiation tolerance of sensitive structures, especially in the setting of previous treatment. OBJECTIVE:To evaluate whether intraoperative brachytherapy with short-range sources allows therapeutic dose delivery without damaging sensitive structures. METHODS:The median doses of previous treatment were 3000 cGy (range, 1800-7200 cGy) for 8 patients with primary/recurrent and 17 patients with metastatic spinal tumors and 5040 cGy (range, 1300-6040 cGy) for 5 patients with locally recurrent and 2 patients with metastatic intracranial tumors. Patients underwent gross total or maximal resection of the tumor and were then treated with an intraoperative brachytherapy plaque consisting of a flexible silicone film incorporating P. A dose of 1000 cGy was delivered to a depth of 1 mm; the percent depth dose was less than 1% at 4 mm from the prescription depth. Median postoperative radiation doses of 2700 cGy (range, 1800-3000 cGy) were delivered to 15 spinal tumor patients and 3000 cGy (range, 1800-3000 cGy) to 3 intracranial tumor patients. The median follow-up was 4.4 months (range, 2.6-23.3 months) for spinal tumor patients and 5.3 months (range, 0.7-16.2) for intracranial tumor patients. RESULTS:At 6-month follow-up, for all spinal tumor patients, local progression-free survival and overall survival rates were both 83.3% (95% confidence interval [CI]: 62.3%-94.3%); for all intracranial tumor patients, the local progression-free survival rate was 62.5% (95% CI: 23.8%-90.9%) and the overall survival rate was 66.7% (95% CI: 26.7%-92.9%). There were no intraoperative or postoperative complications secondary to radiotherapy. CONCLUSION/CONCLUSIONS:Use of the P brachytherapy plaque is technically simple and not associated with increased risk of complications, even after multiple radiation courses. Local control rates were more than 80% in patients with proven radiation-resistant spinal disease.

STUDY DESIGN/METHODS:A retrospective review. OBJECTIVE:To report our approach and results using a contralateral minimally invasive spinal surgical muscle splitting approach that allows visualization of the cyst without extensive removal of the adjacent facet joint. SUMMARY OF BACKGROUND DATA/BACKGROUND:The use of tubular retractors for spinal surgery can potentially minimize tissue injury. Contralateral approaches may be beneficial in visualizing pathology that is located adjacent or under the facet joint. This approach has not been reported previously. METHODS:Sixteen consecutive patients were treated using this approach using tubular retractors and the operating microscope. A retrospective chart and imaging review was conducted to determine operative and clinical measures. Subsequently, patients were contacted to obtain long-term clinical follow-up. RESULTS:Nine patients had an excellent and 5 had a good outcome, with median follow-up of 18 months, 2 patients were lost due to lack of follow-up. The mean operative time was 105 minutes and in all cases the blood loss was <40 mL. No postoperative instability was noted. CONCLUSIONS:A contralateral approach using a tubular retractor system provides excellent visualization of the facet cyst allowing safe cyst resection and nerve root decompression without compromising the facet joint. Larger case series with longer follow-up are needed to assess stability.

OBJECT In this paper, the authors' goal was to determine the outcome of reoperation for recurrent epidural spinal cord compression in patients with metastatic spine disease. METHODS A retrospective chart review was conducted of all patients who underwent spine surgery at the Memorial Sloan-Kettering Cancer Center between 1996 and 2007. Thirty-nine patients who underwent reoperation of the spine at the level previously treated with surgery were identified. Only patients whose reoperation was performed because of tumor recurrence leading to high-grade epidural spinal cord compression or recurrence with no further radiation options were included in the study. Patients who underwent reoperations exclusively for instrumentation failure were excluded. All patients underwent additional decompression via a posterolateral approach without removal of the spinal instrumentation. RESULTS Patients underwent 1-4 reoperations at the same level. A median survival time of 12.4 months was noted after the first reoperation, and a median survival time of 9.1 months was noted after the last reoperation. At last follow-up 22 (65%) of 34 patients were ambulatory at the time of last follow-up or death, and the median time between loss-of-ambulation and death was 1 month. Functional status was maintained or improved by one Eastern Cooperative Oncology Group grade in 97% of patients. A major surgical complication rate of 5% was noted. CONCLUSIONS Reoperation represents a viable option in patients with high-grade epidural spinal cord compression who have recurrent metastatic tumors at previously operated spinal levels. In carefully selected patients, reoperation can prolong ambulation and result in good functional and neurological outcomes.

OBJECTIVE:The evolution of imaging techniques, along with highly effective radiation options has changed the way metastatic epidural tumors are treated. While high-grade epidural spinal cord compression (ESCC) frequently serves as an indication for surgical decompression, no consensus exists in the literature about the precise definition of this term. The advancement of the treatment paradigms in patients with metastatic tumors for the spine requires a clear grading scheme of ESCC. The degree of ESCC often serves as a major determinant in the decision to operate or irradiate. The purpose of this study was to determine the reliability and validity of a 6-point, MR imaging-based grading system for ESCC. METHODS:To determine the reliability of the grading scale, a survey was distributed to 7 spine surgeons who participate in the Spine Oncology Study Group. The MR images of 25 cervical or thoracic spinal tumors were distributed consisting of 1 sagittal image and 3 axial images at the identical level including T1-weighted, T2-weighted, and Gd-enhanced T1-weighted images. The survey was administered 3 times at 2-week intervals. The inter- and intrarater reliability was assessed. RESULTS:The inter- and intrarater reliability ranged from good to excellent when surgeons were asked to rate the degree of spinal cord compression using T2-weighted axial images. The T2-weighted images were superior indicators of ESCC compared with T1-weighted images with and without Gd. CONCLUSIONS:The ESCC scale provides a valid and reliable instrument that may be used to describe the degree of ESCC based on T2-weighted MR images. This scale accounts for recent advances in the treatment of spinal metastases and may be used to provide an ESCC classification scheme for multicenter clinical trial and outcome studies.

STUDY DESIGN/METHODS:Systematic review and evidence appraisal. OBJECTIVE:To evaluate the optimal treatment for patients with spinal cord compression secondary to solid metastases and in patients with solitary renal metastases, without spinal cord compression. METHODS:Focused Medline and OVID database searches were conducted using relevant keywords. Only clinical articles that evaluated specific end points of interest were included in the literature review. The quality of evidence provided by each article was assessed using the ATS guidelines. The expert opinion was synthesized based on the evidence and rated as strong or weak, depending on the quality of the supporting literature. RESULTS:Twelve surgical and 7 radiation clinical series were identified that evaluated post-treatment ambulation in patients with metastatic spinal cord compression. Only 1 surgical article met the criteria for moderate quality evidence while the remaining surgical and radiation articles presented very low quality of evidence. All articles that evaluated treatment of solitary renal metastases presented very low quality of evidence. CONCLUSION/CONCLUSIONS:A strong recommendation is made for patients with high-grade cord compression due to solid tumor metastases to undergo surgical decompression with stabilization followed by radiation therapy. A weak recommendation is made for patients with solitary renal metastases without spinal cord compression to undergo spinal stereotactic radiosurgery.

PURPOSE/OBJECTIVE:Single-fraction image-guided intensity-modulated radiation therapy (IG-IMRT) allows for tumoricidal treatment of traditionally radioresistant cancers while sparing critical adjacent structures. Risk of vertebral fracture after IG-IMRT for spinal metastases has not been defined. PATIENTS AND METHODS/METHODS:We evaluated 62 consecutive patients undergoing single fraction IG-IMRT at 71 sites for solid organ metastases. A neuroradiologist and three spine surgeons evaluated prospectively obtained magnetic resonance/computed tomography (CT) imaging studies for post-treatment fracture development and tumor recurrence. RESULTS:Fracture progression was noted in 27 vertebrae (39%). Multivariate logistic regression analysis showed that CT appearance, lesion location, and percent vertebral body involvement independently predicted fracture progression. Lesions located between T10 and the sacrum were 4.6 times more likely to fracture than were lesions above T10 (95% CI, 1.1 to 19.7). Lytic lesions were 6.8 times more likely to fracture than were sclerotic and mixed lesions (95% CI, 1.4 to 33.3). As percent vertebral body involvement increased, odds of fracture also increased. Patients with fracture progression had significantly higher narcotic use, change in Karnofsky performance score, and a strong trend toward higher pain scores. Local tumor progression occurred in seven patients and contributed to one fracture. Obesity, posterior element involvement, bisphosphonate use, and local kyphosis did not confer increased risk. CONCLUSION/CONCLUSIONS:Vertebral fracture is common after single fraction IG-IMRT for metastatic spine lesions. Lytic disease involving more than 40% of the vertebral body and location at or below T10 confer a high risk of fracture, the presence of which yields significantly poorer clinical outcomes. These results may help clinicians identify high-risk patients who would benefit from prophylactic vertebro- or kyphoplasty.

OBJECTIVE:To determine the accuracy of [(18)F]fluorodeoxyglucose (FDG) positron emission tomography (PET) in the diagnosis of vertebral metastases in patients with cancer using needle-biopsy results and patient follow-up data. METHODS:A retrospective chart review of all patients who underwent a needle biopsy of a spinal lesion and underwent FDG-PET within 6 weeks of the biopsy was performed. Biopsy results and magnetic resonance imaging and computed tomographic appearance of the biopsied lesion, as well as long-term clinical follow-up data, were recorded for each patient. A total of 82 patients with solid tumors and hematological spine metastases were included in this study. RESULTS:The mean standardized uptake values of lesions with active cancer were 7.1 and 2.1 in benign lesions (P < 0.02). In patients with metastatic solid tumors, the mean standardized uptake value was 7.3. Stratification of solid tumor lesions according to whether they had a sclerotic appearance on computed tomographic scans showed that FDG-PET was a significantly better predictor of cancer status in lytic or mixed lesions. In patients with a history of solid tumors, there was 100% concordance between the FDG-PET and needle-biopsy diagnoses in nonsclerotic lesions, when the standardized uptake value cutoff of 2 was used. CONCLUSION/CONCLUSIONS:FDG-PET is an accurate screening test for vertebral metastases in cancer patients. It is especially accurate in patients with nonsclerotic vertebral lesions and a history of solid malignancy.

Malignant primary tumors of the spine present difficult management problems because of the complexities of en bloc resection and their chemoresistance and radioresistance. A combination of radiation techniques and advances in systemic therapy may ultimately provide improved local tumor control and cure for these treatment-resistant tumors.