MIS technique for separation surgery in lumbar spine metastatic disease.

Around 40% of cancer patients present with spinal metastases (SM), the lumbar spine being the second most involved site (15%-30%) after the thoracic (60%-80%). Since the development of separation surgery, minimally invasive surgery (MIS) has increasingly been applied to approach SM, mirroring benefits yielded in the degenerative realm. Moreover, preoperative embolization potentially enhances local control for certain radioresistant histologies. Carbon fiber-reinforced PEEK hardware reduces image artifact, facilitating more accurate follow-up and radiotherapeutic planning. Additionally, short-segment cement-augmented constructs may be beneficial to decrease surgical morbidity and operative risk in this population. The authors present a lumbar spinal metastasis treated with MIS techniques. The video can be found here: https://stream.cadmore.media/r10.3171/2024.1.FOCVID23222.

Thoracic root-related intradural extramedullary cavernoma presenting with subarachnoid hemorrhage: illustrative case.

BACKGROUND: Just 5% of all cavernomas are located in the spine. Thoracic root-related subtypes are the rarest, with a total of 14 cases reported in the literature to date. Among them, only 4 presented with subarachnoid hemorrhage (SAH). OBSERVATIONS: A 65-year-old female presented after an ictus of headache with no neurological deficits. Computed tomography (CT) demonstrated sulcal SAH, with the remainder of the workup nondiagnostic for etiology. Three weeks later, she re-presented with acute thoracic back pain and thoracic myelopathy. CT and magnetic resonance imaging suggested dubiously a T9-10 disc herniation with spinal cord compression. Surgical decompression and resection were then planned. Intraoperative ultrasound (IUS) demonstrated an intradural extramedullary lesion, confirmed to be cavernoma. Complete resection was achieved, and the patient was discharged a few days postoperatively to inpatient rehabilitation. LESSONS: Although spine imaging is deemed to be low yield in the evaluation of cryptogenic SAH, algorithms can be revisited even in the absence of spine-related symptoms. Surgeons can be prepared to change the initial surgical plan, especially when preoperative imaging is unclear. IUS is a powerful tool to assess the thecal sac after its exposure and to help guide this decision, as in this rare entity.

Vertebral Compression Fracture After Spine Stereotactic Body Radiotherapy: The Role of Vertebral Endplate Disruption.

BACKGROUND AND OBJECTIVES: Vertebral compression fracture (VCF) is a common, but serious toxicity of spinal stereotactic body radiotherapy (SBRT). Several variables that place patients at high risk of VCF have previously been identified, including advanced Spinal Instability Neoplastic Score (SINS), a widely adopted clinical decision criterion to assess spinal instability. We examine the role of tumoral endplate (EP) disruption in the risk of VCF and attempt to incorporate it into a simple risk stratification system. METHODS: This study was a retrospective cohort study from a single institution. Demographic and treatment information was collected for patients who received spinal SBRT between 2013 and 2019. EP disruption was noted on pre-SBRT computed tomography scan. The primary end point of 1-year cumulative incidence of VCF was assessed on follow-up MRI and computed tomography scans at 3-month intervals after treatment. RESULTS: A total of 111 patients were included. The median follow-up was 18 months. Approximately 48 patients (43%) had at least one EP disruption. Twenty patients (18%) experienced a VCF at a median of 5.2 months from SBRT. Patients with at least one EP disruption were more likely to experience VCF than those with no EP disruption (29% vs 6%, P < .001). A nomogram was created using the variables of EP disruption, a SINS of ≥7, and adverse histology. Patients were stratified into groups at low and high risk of VCF, which were associated with 2% and 38% risk of VCF ( P < .001). CONCLUSION: EP disruption is a novel risk factor for VCF in patients who will undergo spinal SBRT. A simple nomogram incorporating EP disruption, adverse histology, and SINS score is effective for quickly assessing risk of VCF. These data require validation in prospective studies and could be helpful in counseling patients regarding VCF risk and referring for prophylactic interventions in high-risk populations.

Resection of intradural intramedullary subependymoma of the cervicothoracic spine: 2-dimensional operative video.

This video presents the case of a 44-year-old male with a 2-year history of pain in the left upper extremity that had worsened over the course of the last 6 months with associated weakened grip strength and had extended into his right arm. T2-weighted sagittal and axial MRI demonstrated an expansive nonenhancing solid intramedullary lesion extending from C5 to T1. The patient underwent a C5-T1 laminectomy and laminoplasty with near-complete resection of the intradural intramedullary subependymoma. At 3 months' follow-up, he reported doing well and had experienced significant improvement in motor strength with ongoing therapies.

Novel Intrafraction Motion Tracking During Postoperative Spine Stereotactic Irradiation for a Patient With Carbon Fiber Fixation Hardware.

Carbon-fiber reinforced (CFR) polyetheretherketone hardware is an alternative to traditional metal hardware used for spinal fixation surgeries before postoperative radiation therapy for patients with spinal metastases. CFR hardware's radiolucency decreases metal artifact, improving visualization and accuracy of treatment planning. We present the first clinical use and proof of principle of CFR spinal hardware with tantalum markers used for successful tracking of intrafraction motion (IM) using Varian TrueBeam IMR (Intrafraction Motion Review) software module during postoperative spine stereotactic radiation. A 63-year-old woman with history of endometrial cancer presented with acute back pain. Imaging demonstrated pathologic T12 vertebral fracture with cord compression. She underwent T12 vertebrectomy with circumferential decompression and posterior instrumented T10-L2 fusion at our facility using CFR-polyetheretherketone hardware with tantalum screw markers followed by postoperative stereotactic body radiation therapy to 3000 cGy in 5 fractions delivered to T11-T12. Tantalum screw markers were used for IMR tracking. During irradiation, 260 kV images were acquired, and IMR software was able to identify and track markers. During the entire treatment, the IM motions were less than 3 mm. This is the first presented case of CFR spinal hardware with tantalum markers used for successful IMR tracking of IM during daily spine stereotactic treatment. Future work will be needed to improve workflow and create a spine-specific IMR protocol.

Trends in Leadership Among Neurosurgical Oncology Fellowships.

OBJECTIVE: To examine current neurosurgical oncology leadership trends and provide a guide for those interested in obtaining fellowship directorship, we investigated fellowship director (FD) demographic, educational, and leadership characteristics. METHODS: The American Association of Neurological Surgeons Academic Fellowship Directory and Committee on Advanced Subspecialty Training websites were reviewed for current U.S. program FDs for which data were collected using online resources and surveys. RESULTS: In total, 23 FDs (20 male and 3 female) were represented whose mean age was 52.4 years (standard deviation = 8.7). Our analysis found 65% of current neurosurgical oncology FDs to be singularly trained in neurosurgical oncology, with 8.7% possessing multiple fellowships and 34.8% possessing additional degrees. Fellowship programs producing the most FDs were University of Texas MD Anderson (4), Memorial Sloan Kettering (3), and University of Miami (2). FDs possessed an average of 148 publications, 6423 citations, and an h-index of 33.9. H-index had a high-positive correlation with age and time from residency graduation but not duration of FD appointment. Among survey respondents, 91.7% reported membership and 75% reported leadership positions among national academic societies, whereas 66.7% reported holding journal-editorial positions. The mean age of FD appointment was 46.8 years, with a mean time from fellowship completion to FD appointment of 10.0 years. CONCLUSIONS: Through the characterization of current leaders in the field, we provide valuable information with regards to training location trends, research productivity goals, career timelines, and target journal/national academic society involvement worth consideration among young trainees when making career decisions and plans.

Metastatic Breast Cancer to the Spine: Incidence of Somatic Gene Alterations and Association of Targeted Therapies With Overall Survival.

BACKGROUND: The increase in use of targeted systemic therapies in cancer treatments has catalyzed the importance of identifying patient- and tumor-specific somatic mutations, especially regarding metastatic disease. Mutations found to be most prevalent in patients with metastatic breast cancer include TP53, PI3K, and CDH1. OBJECTIVE: To determine the incidence of somatic mutations in patients with metastatic breast cancer to the spine (MBCS). To determine if a difference exists in overall survival (OS), progression-free survival, and progression of motor symptoms between patients who do or do not undergo targeted systemic therapy after treatment for MBCS. METHODS: This is a retrospective study of patients with MBCS. Review of gene sequencing reports was conducted to calculate the prevalence of various somatic gene mutations within this population. Those patients who then underwent treatment (surgery/radiation) for their diagnosis of MBCS between 2010 and 2020 were subcategorized. The use of targeted systemic therapy in the post-treatment period was identified, and post-treatment OS, progression-free survival, and progression of motor deficits were calculated for this subpopulation. RESULTS: A total of 131 patients were included in the final analysis with 56% of patients found to have a PI3K mutation. Patients who received targeted systemic therapies were found to have a significantly longer OS compared with those who did not receive targeted systemic therapies. CONCLUSION: The results of this study demonstrate that there is an increased prevalence of PI3K mutations in patients with MBCS and there are a significant survival benefit and delay in progression of motor symptoms associated with using targeted systemic therapies for adjuvant treatment.

Variation in Cervical Pedicle Morphology: Important Considerations for Posterior Cervical Procedures.

BACKGROUND: Safe posterior cervical spine surgery requires in-depth understanding of the surgical anatomy and common variations. The cervical pedicle attachment site to the vertebral body (VB) affects the location of exiting nerve roots and warrants preoperative evaluation. The relative site of attachment of the cervical pedicle has not been previously described. OBJECTIVE: To describe the site of the pedicle attachment to the VB in the subaxial cervical spine. METHODS: Cervical spine computed tomography scans without any structural, degenerative, or traumatic pathology as read by a board-certified neuroradiologist during 2021 were reviewed. Multiplanar reconstructions were created and cross-registered. The pedicle's attachment to the VB was measured relative to the VB height using a novel calculation system. RESULTS: Fifty computed tomography scans met inclusion criteria yielding 600 total pedicles between C3-T1 (100 per level). The average patient age was 26 ± 5.3 years, and 21/50 (42%) were female. 468/600 (78%) pedicles attached in the cranial third of the VB, 132/600 (22%) attached in the middle third, and 0 attached to the caudal third. The highest prevalence of variant anatomy occurred at C3 (36/100 C3 pedicles; 36%). CONCLUSION: In the subaxial cervical spine, pedicles frequently attach to the top third of the VB, but significant variation is observed. The rate of variation is highest at C3 and decreases linearly with caudal progression down the subaxial cervical spine to T1. This is the first report investigating this morphological phenomenon.

Cervicothoracic junction instrumentation strategies following separation surgery for spinal metastases.

OBJECTIVE: The cervicothoracic junction (CTJ) is a challenging region to stabilize after tumor resection for metastatic spine disease. The objective of this study was to describe the outcomes of patients who underwent posterolateral decompression and instrumented fusion (i.e., separation surgery across the CTJ for instability due to metastatic disease). METHODS: The authors performed a single-institution retrospective study of a prospectively collected cohort of patients who underwent single-approach posterior decompression and instrumented fusion across the CTJ for metastatic spine disease between 2011 and 2018. Adult patients (≥ 18 years old) who presented with mechanical instability, myelopathy, and radiculopathy secondary to metastatic epidural spinal cord compression (MESCC) of the CTJ (C7-T1) from 2011 to 2018 were included. RESULTS: Seventy-nine patients were included, with a mean age of 62.1 years. The most common primary malignancies were non-small cell lung (n = 17), renal cell (11), and prostate (8) carcinoma. The median number of levels decompressed and construct length were 3 and 7, respectively. The average operative time, blood loss, and length of stay were 179.2 minutes, 600.5 ml, and 7.7 days, respectively. Overall, 58 patients received adjuvant radiation, and median dose, fractions, and time from surgery were 27 Gy, 3 fractions, and 20 days, respectively. All patients underwent lateral mass and pedicle screw instrumentation. Forty-nine patients had tapered rods (4.0/5.5 mm or 3.5/5.5 mm), 29 had fixed-diameter rods (3.5 mm or 4.0 mm), and 1 had both. Ten patients required anterior reconstruction with poly-methyl-methacrylate. The overall complication rate was 18.8% (6 patients with wound-related complications, 7 with hardware-related complications, 1 with both, and 1 with other). For the 8 patients (10%) with hardware failure, 7 had tapered rods, all 8 had cervical screw pullout, and 1 patient also experienced rod/screw fracture. The average time to hardware failure was 146.8 days. The 2-year cumulative incidence rate of hardware failure was 11.1% (95% CI 3.7%-18.5%). There were 55 deceased patients, and the median (95% CI) overall survival period was 7.97 (5.79-12.60) months. For survivors, the median (range) follow-up was 12.94 (1.94-71.80) months. CONCLUSIONS: Instrumented fusion across the CTJ demonstrated an 18.8% rate of postoperative complications and an 11% overall 2-year rate of hardware failure in patients who underwent metastatic epidural tumor decompression and stabilization.

Long-Term Clinical Outcomes of Patients with Colorectal Cancer with Metastatic Epidural Spinal Cord Compression Treated with Hybrid Therapy (Surgery Followed by Stereotactic Body Radiation Therapy).

BACKGROUND: Hybrid therapy, consisting of separation surgery followed by stereotactic body radiation therapy, has become the mainstay treatment for radioresistant spinal metastases. Histology-specific outcomes for hybrid therapy are scarce. In clinical practice, colorectal cancer (CRC) is particularly thought to have poor outcomes regarding spinal metastases. The goal of this study was to evaluate clinical outcomes for patients treated with hybrid therapy for spinal metastases from CRC. METHODS: This retrospective study was performed at a tertiary cancer center. Adult patients with CRC spinal metastasis who were treated with hybrid therapy for high-grade epidural spinal cord or nerve root compression from 2005 to 2020 were included. Outcome variables evaluated included patient demographics, overall survival and progression-free survival, surgical and radiation complications, and clinical-genomic correlations. RESULTS: Inclusion criteria were met by 50 patients. Progression of disease occurred in 7 (14%) patients at the index level, requiring reoperation and/or reirradiation at a mean of 400 days after surgery. Postoperative complications occurred in 16% of patients, with 3 (6%) requiring intervention. APC exon 14 and 16 mutations were found in 15 of 17 patients tested and in all 3 of 7 local failures tested. Twenty patients (40%) underwent further radiation due to disease progression at other spinal levels. CONCLUSIONS: Hybrid therapy in patients with CRC resulted in 86.7% local control at 2 years after surgery, with limited complications. APC mutations are commonly present in CRC patients with spine metastases and may suggest worse prognosis. Patients with CRC spinal metastases commonly progress outside the index treatment level.

The Impact of Targetable Mutations on Clinical Outcomes of Metastatic Epidural Spinal Cord Compression in Patients With Non-Small-Cell Lung Cancer Treated With Hybrid Therapy (Surgery Followed by Stereotactic Body Radiation Therapy).

BACKGROUND: In treatment of metastatic epidural spinal cord compression (MESCC), hybrid therapy, consisting of separation surgery, followed by stereotactic body radiation therapy, has become the mainstay of treatment for radioresistant pathologies, such as non-small-cell lung cancer (NSCLC). OBJECTIVE: To evaluate clinical outcomes of MESCC secondary to NSCLC treated with hybrid therapy and to identify clinical and molecular prognostic predictors. METHODS: This is a single-center, retrospective study. Adult patients (≥18 years old) with pathologically confirmed NSCLC and spinal metastasis who were treated with hybrid therapy for high-grade MESCC or nerve root compression from 2012 to 2019 are included. Outcome variables evaluated included overall survival (OS) and progression-free survival, local tumor control in the competing risks setting, surgical and radiation complications, and clinical-genomic correlations. RESULTS: One hundred and three patients met inclusion criteria. The median OS for this cohort was 6.5 months, with progression of disease noted in 5 (5%) patients at the index tumor level requiring reoperation and/or reirradiation at a mean of 802 days after postoperative stereotactic body radiation therapy. The 2-year local control rate was 94.6% (95% CI: 89.8-99.3). Epidermal growth factor receptor (EGFR) treatment-naïve patients who initiated EGFR-targeted therapy after hybrid therapy had significantly longer OS (hazard ratio 0.47, 95% CI 0.23-0.95, P = .04) even after adjusting for smoking status. The presence of EGFR exon 21 mutation was predictive of improved progression-free survival. CONCLUSION: Hybrid therapy in NSCLC resulted in 95% local control at 2 years after surgery. EGFR treatment-naïve patients initiating therapy after hybrid therapy had significantly improved survival advantage. EGFR-targeted therapy initiated before hybrid therapy did not confer survival benefit.

Exceptional Cases of Spinal Cord Stimulation for the Treatment of Refractory Cancer-Related Pain.

OBJECTIVES: Cancer pain has traditionally been managed with opioids, adjuvant medications, and interventions including injections, neural blockade, and intrathecal pump (ITP). Spinal cord stimulation (SCS), although increasingly used for conditions such as failed back surgery syndrome and complex regional pain syndrome, is not currently recommended for cancer pain. However, patients with cancer-related pain have demonstrated benefit with SCS. We sought to better characterize these patients and the benefit of SCS in exceptional cases of refractory pain secondary to progression of disease or evolving treatment-related complications. MATERIALS AND METHODS: This was a single-center, retrospective case series at a tertiary cancer center. Adults ≥18 years old with active cancer and evolving pain secondary to disease progression or treatment, whose symptoms were refractory to systemic opioids, and who underwent SCS trial followed by percutaneous implantation between 2016 and 2021 were included. Descriptive statistics included mean, SD, median, and interquartile range (IQR). RESULTS: Eight patients met the inclusion criteria. The average age at SCS trial was 60.0 (SD: ±11.6) years, and 50% were men. Compared with baseline, the median (IQR) change in pain score by numeric rating scale (NRS) after trial was -3 (2). At an average of 14 days after implant, the median (IQR) change in NRS and daily oral morphine equivalents were -2 (3.5) and -126 mg (1095 mg), respectively. At a median of 63 days after implant, the corresponding values were -3 (0.75) and -96 mg (711 mg). There was no significant change in adjuvant therapies after SCS implantation at follow-up. Six patients were discharged within two days after implantation. Two patients were readmitted for pain control within the follow-up period. CONCLUSIONS: In patients with cancer-related pain, SCS may significantly relieve pain, reduce systemic daily opioid consumption, and potentially decrease hospital length of stay and readmission for pain control. It may be appropriate to consider an SCS trial before ITP in select cases of cancer-related pain.

Real-time ultrasound guidance in the endoscopic endonasal resection of a retro-odontoid pannus: Technical note and case illustration.

Background and Objectives: Odontoidectomy is a surgical procedure indicated in the setting of various pathologies, with the main goal of decompressing the ventral brain stem and spinal cord as a result of irreducible compression at the craniovertebral junction. The endoscopic endonasal approach has been increasingly used as an alternative to the transoral approach as it provides a straightforward, panoramic, and direct approach to the odontoid process. In addition, intraoperative ultrasound (US) guidance is a technique that can optimize safety and surgical outcomes in this context. It is used as an adjunct to neuronavigation and provides intraoperative confirmation of decompression of craniovertebral junction structures in real time. The authors aim to present the use and safe application of real-time intraoperative US guidance during endonasal endoscopic resection of a retro-odontoid pannus. Methods: A retrospective chart review of a single case was performed and presented herein as a case report and narrated operative video. Results: A minimally invasive US transducer was used intraoperatively to guide the resection of a retro-odontoid pannus and confirm spinal cord decompression in real time. Postoperative examination of the patient revealed immediate neurological improvement. Conclusions: Intraoperative ultrasonography is a well described and useful modality in neurosurgery. However, the use of intraoperative US guidance during endonasal endoscopic approaches to the craniovertebral junction has not been previously described. As demonstrated in this technical note, the authors show that this imaging modality can be added to the ever-evolving armamentarium of neurosurgeons to safely guide the decompression of neural structures within the craniocervical junction with good surgical outcomes.

Patient outcomes following implementation of an enhanced recovery after surgery pathway for patients with metastatic spine tumors.

BACKGROUND: Metastatic spine tumor surgery consists of palliative operations performed on frail patients with multiple medical comorbidities. Enhanced recovery after surgery (ERAS) programs involve an evidence-based, multidisciplinary approach to improve perioperative outcomes. This study presents clinical outcomes of a metastatic spine tumor ERAS pathway implemented at a tertiary cancer center. METHODS: The metastatic spine tumor ERAS program launched in April 2019, and data from January 2018 to May 2020 were reviewed. Measured outcomes included the following: hospital length of stay (LOS), time to ambulation, urinary catheter duration, time to resumption of diet, intraoperative fluid intake, estimated blood loss (EBL), and intraoperative and postoperative day 0-5 cumulative opioid use (morphine milligram equivalent [MME]). RESULTS: A total of 390 patients were included in the final analysis: 177 consecutive patients undergoing metastatic spine tumor surgery enrolled in the ERAS program and 213 consecutive pre-ERAS patients. Although the mean case durations were similar in the ERAS and pre-ERAS cohorts (265 vs. 274 min; p = .22), the ERAS cohort had decreased EBL (157 vs. 215 ml; p = .003), decreased postoperative day 0-5 cumulative mean opioid use (178 vs. 396 MME; p < .0001), earlier ambulation (mean, 34 vs. 57 h; p = .0001), earlier discontinuation of urinary catheters (mean, 36 vs. 56 h; p < .001), and shorter LOS (5.4 vs. 7.5 days; p < .0001). CONCLUSIONS: The implementation of a multidisciplinary ERAS program designed for metastatic spine tumor surgery led to improved clinical quality metrics, including shorter hospitalizations and significant reductions in opioid consumption.

The role of neoadjuvant denosumab in the treatment of aneurysmal bone cysts: a case series and review of the literature.

OBJECTIVE: Aneurysmal bone cysts (ABCs) are benign cystic lesions most commonly occurring in the long bones of pediatric patients. Spinal ABCs may be difficult to resect given their invasive, locally destructive nature, proximity to critical structures such as the spinal cord, and their intrinsic hypervascularity, for which complete embolization is often constrained by radiculomedullary segmental feeders. Denosumab, a monoclonal antibody that binds the receptor activator of nuclear factor kappa B (NF-κB) ligand, has been utilized in the treatment of ABCs most often as a rescue therapy for recurrent disease. Here, the authors present 3 cases of neoadjuvant denosumab use in surgically unresectable tumors to calcify and devascularize the lesions, allowing for safer, more complete resection. METHODS: This is a single-center, retrospective case series treated at a tertiary care cancer center. The authors present 3 cases of spinal ABC treated with neoadjuvant denosumab. RESULTS: All 3 patients experienced calcification, size reduction, and a significant decrease in the vascularity of their ABCs on denosumab therapy. None of the patients developed new neurological deficits while on denosumab. Subsequently, all underwent resection. One patient continued denosumab during the immediate postoperative period because a subtotal resection had been performed, with stabilization of the residual disease. No complications were associated with denosumab administration. CONCLUSIONS: The use of denosumab in unresectable ABCs can cause calcification and devascularization, making safe resection more likely.

Incorporation of Blood and Fluid Management Within an Enhanced Recovery after Surgery Protocol in Complex Spine Surgery.

STUDY DESIGN: retrospective review. OBJECTIVE: Enhanced Recovery After Surgery (ERAS) is a multidisciplinary set of evidence-based interventions to reduce morbidity and accelerate postoperative recovery. Complex spine surgery carries high risks of perioperative blood loss, blood transfusion, and suboptimal fluid states. This study evaluates the efficacy of a perioperative fluid and blood management component comprised of a restrictive transfusion policy, goal directed fluid management, number of tranexamic acid (TXA) utilization, and autologous blood transfusion within our ERAS protocol for complex spine surgery. METHODS: A retrospective review compared patients undergoing elective complex spine surgery prior to and following implementation of an ERAS protocol with intraoperative blood and fluid management. Outcomes included incidence of blood transfusion, estimated blood loss, intraoperative crystalloids administered, frequency of intraoperative TXA utilized, incidence of patients extubated within the operating room (OR), intensive care unit (ICU) admission, and hospital length of stay. RESULTS: Following implementation, the rate of blood transfusion decreased by 11.7%(P = .017) and average crystalloid infusion was reduced 680 mL per case(P < .001). Intraoperative blood loss decreased on average 342 mL per case(P = .001) and TXA use increased significantly by 25%(P < .001). Postoperative ICU admissions declined by 8.5%(P = .071); extubation within the OR increased by 13.3%(P = .005). CONCLUSIONS: This protocol presents a unique perspective with the inclusion of an interdisciplinary and comprehensive blood and fluid management protocol as an integral part of our ERAS pathway for complex spine surgery. These results indicate that a standardized approach is associated with reduced rates of blood transfusion and optimized fluid states which was correlated with decreased postoperative ICU admissions.