Sahgal, Arjun

Abstract Vertebral metastatic disease results from many types of cancer and can have a devastating impact on patient mobility, psychological health, quality of life, and ultimately overall patient survival. However, the development of radiotherapy and surgical techniques has rapidly surged in conjunction with ongoing advances in basic science and translational studies. In this review, we discuss the paradigm shift in our understanding of the epidemiology and treatment algorithms for spinal oncology, ranging from preoperative optimization strategies, radiation and surgical techniques, the utilization of molecular markers and targeted therapeutics in medical oncology, and prognostication tools that underscore a new multidisciplinary approach to spinal oncology care.

Study Design Narrative Review. Objectives To summarize the scientific contributions generated from the AO Spine Knowledge Forum Tumor (AOSKFT) databases, focusing on primary spine tumors, and highlight key findings, research trends, and future directions. Methods Data from the Primary Tumor Retrospective (PT-Retro) and Primary Tumor Research Outcome Network (PTRON) registries were analyzed. The nineteen studies included were peer-reviewed manuscripts focused on primary spine tumors, excluding abstracts, book chapters, systematic reviews, and metastatic studies. Results The PT-Retro registry compiled data from 1495 patients across 18 primary tumor histologies, offering insights into recurrence, survival, and treatment paradigms. Key findings emphasize the importance of Enneking-appropriate (EA) resection in improving survival and reducing recurrence in tumors such as chordoma, chondrosarcoma, and osteosarcoma. Genetic markers, including hTERT promoter mutations and rs2305089 SNP, were linked to prognosis in specific histologies. Benign tumors, such as giant cell tumors and aneurysmal bone cysts, demonstrated variable outcomes with different surgical approaches and selective arterial embolization. Conclusions The AOSKFT registries have significantly advanced knowledge in primary spine tumor management, emphasizing preoperative staging, surgical margins, and multidisciplinary approaches. International, multicentric registries are essential for studying rare diseases like primary spine tumors, enabling robust data collection, improved statistical power, and broader applicability of findings across diverse clinical settings. Ongoing prospective data collection through PTRON will further refine evidence-based care for these rare and challenging conditions.

BACKGROUND AND OBJECTIVES: The Patient-Generated Subjective Global Assessment (PG-SGA) is a standardized tool for assessing malnutrition in patients with cancer. The primary aim of this study was to assess the impact of preoperative nutritional status as measured by PG-SGA on survival in patients requiring surgical intervention and/or radiotherapy for spinal metastases. METHODS: Patients with spinal metastases who underwent surgery and/or radiation therapy for symptomatic spinal metastases were enrolled in the AO Spine Metastatic Tumor Research and Outcomes Network, a prospective international multicenter research registry, between September 2017 and August 2022. Using the PG-SGA, nutritional status was classified into 3 categories: A, well nourished; B, moderately malnourished; and C, severely malnourished. RESULTS: A total of 589 patients met the inclusion criteria; 362 were classified as well nourished (61%), 159 were moderately malnourished (27%), and 68 were severely malnourished (12%). The median survival was 491 days, 328 days, and 117 days for well-nourished, moderately malnourished, and severely malnourished patients, respectively. In the multivariate analyses, severe malnourishment (HR 2.5 95% CI 1.4-4.3, P < .01) and an ECOG performance status of 3 or 4 (HR 2.7 95% CI 1.2-6.0) remained associated with significantly worse survival. CONCLUSION: Malnutrition as measured by the PG-SGA demonstrated to be significantly and independently associated with postoperative survival. The PG-SGA is a simple and useful tool to identify spinal metastases patients at risk of early postoperative mortality, and inclusion in the preoperative evaluation of these patients should be considered.

Study Design This study is part of the AO Spine Metastatic Tumor Research and Outcomes Network [MTRON], an international multicenter prospective observational registry including patients with spinal metastases. Objectives This study aims to elucidate the incidence of surgical complications, their risk factors and consequent effects on survival outcomes, hospital length of stay, and overall health-related quality of life (HRQOL) parameters in a large cohort of patients affected by spinal metastases who were surgically treated. Methods Available data from February 2017 to July 2023 were analyzed. The primary outcome of this study was the evaluation of the incidence of intraoperative and postoperative adverse events (AEs). The secondary outcomes included the assessment of risk factors for surgery-related AEs and the impact of AEs on survival, length of hospital stay and quality of life. Results Among the 1267 patients analyzed, 6.9% experienced intraoperative AEs and 19.3% experienced at least 1 postoperative AE. Several factors resulted to be associated to the occurrence of postoperative AEs: age, smoking habit, poor Eastern Cooperative Oncology Group (ECOG) Performance status, previous radiation therapy at the index target, duration of surgery, number of instrumented levels, simultaneous anterior and posterior approach, presence of metastases at other sites, multiple spinal metastases. Postoperative AEs were associated with reduced survival rates, increased hospital length of stay and poorer HRQOL outcomes, particularly in domains such as neurological function and mental health. In general, surgery substantially improves HRQOL across multiple domains, with these benefits persisting over time despite the occurrence of AEs. However, patients with preoperative risk factors, including comorbidities, smoking, neurological impairment, and prior radiation therapy, experienced less improvement. Conclusions The negative impact of AEs on overall survival and HRQOL could be associated with the presence of some preoperative parameters of frailty that are detected as risk factors for AEs occurrence. This finding emphasizes the need for personalized preoperative assessments and optimized perioperative care strategies.

OBJECTIVE Surgery is typically indicated for mechanical pain in metastatic spine disease or severe neurological compromise, but how radicular pain responds to oncological treatment is not well described. The primary aim of this study was to describe how radicular pain responds to oncological treatment, while secondary aims included pain outcomes between patients with mechanical and tumoral pain and motor improvement in patients with weakness due to nerve root compression. METHODS Patients treated with surgery and/or radiotherapy for spinal metastases were identified from an international multicenter prospective cohort. The primary outcome was the numeric rating scale (NRS) score for pain at 3 months posttreatment. Motor recovery from radicular compression in patients with myotomic weakness and low-grade epidural compression was also analyzed. RESULTS Of 284 patients, 129 (45%) had radicular pain ± axial pain and 155 (55%) had axial pain alone. The two groups did not significantly differ in age, comorbidities, tumor characteristics, or treatment. Two hundred two patients (71%) underwent surgery ± radiotherapy, whereas 82 (29%) had radiotherapy alone. The NRS score of patients with radicular pain improved from 6.7 to 3.4 at 3 months, a statistically significantly higher magnitude than in patients with isolated axial pain (p = 0.021). The NRS score at 3 months was similar for both groups (p = 0.876). Patients with radicular pain experienced a larger improvement with surgery compared with radiotherapy alone (p = 0.007) but had higher pretreatment pain (mean NRS score 7.0 vs 5.6, p = 0.013). Twenty-three patients identified with radicular/myotomic weakness (mean American Spinal Injury Association score 96.3 ± 3.2) at baseline improved 2.1 ± 3.8 points at 3 months. CONCLUSIONS The magnitude of pain improvement for patients with radicular pain following surgery and radiotherapy for metastatic spine disease is higher than for patients with axial pain alone. Surgery is associated with a larger improvement in radicular pain than radiotherapy alone. These results will allow clinicians to tailor treatment options for patients with metastatic spine disease.

Study Design Narrative Review. Objectives To summarize the work of the AO Spine Knowledge Forum Tumor, specifically studies from the Epidemiology, Process and Outcomes in Spine Oncology (EPOSO) study. Methods A narrative review of all published manuscripts from the EPOSO study was undertaken. EPOSO represents a multicenter, prospective registry effort across 10 North American and European sites to enroll patients with metastatic disease of the spine. Results The current review summarized all studies from the EPOSO network, divided into the following five sections: (1) quality of life and satisfaction, (2) overall survival, (3) spinal instability, (4) neurologic outcome in patients with metastatic epidural spinal cord compression or radicular pain, and (5) patient and tumor-specific factors. Several important findings were elucidated. Patient evaluation should include SINS, nutritional status, severity and duration of neurologic deficit, extent of metastatic tumor burden, and differentiation of axial from radicular pain. Moreover, SOSGOQ2.0 serves as a useful and validated instrument for patient-reported outcome instrument. Despite the palliative nature of metastatic spine surgery, clear improvement in quality-of-life is seen. Even in patients with short-survival, the remaining weeks and months of life result in improved quality-of-life. Metastatic spine surgery often improves neurologic function, potentially enhancing survival through increased performance status. Conclusions Several noteworthy results have come from the EPOSO network, highlighting important trends in metastatic spine care. The AO Spine Knowledge Forum Tumor has helped advancing metastatic spine tumor research as well as ensure these new findings reach and benefit clinicians and their patients.

BACKGROUND AND OBJECTIVES: Aggressive resection for primary tumors of the spine are associated with a high rate of adverse events (AEs), but the impact of AEs on patient-reported outcomes (PROs) remains unknown and is critical to the shared decision-making. Our primary objective was to assess the impact of surgical AEs on PROs using an international registry. Assessing the impact on clinical outcomes and identifying risk factors for AEs were our secondary objectives. METHODS: Patients who underwent surgery for a primary spinal tumor were selected through the Primary Tumor Research and Outcomes Network. Our primary outcome was the impact of AEs on PROs at 3 and 12 months after surgery (measured with Spinal Oncology Study Group Outcomes Questionnaire, Short-Form 36, and EuroQol 5 Dimension). We also assessed the impact on clinical outcomes (local control, surgical margins, readmission, reoperation, and mortality). We stratified our results according to severity of AEs, histology, and type of resection. RESULTS: 374 patients met inclusion criteria (219 males/155 females). The mean age of the cohort was 48.7 years. The most frequent histology was chordoma (37.3%) followed by chondrosarcoma (8.8%). Sixty-seven patients (17.9%) experienced at least 1 intraoperative AE and 117 patients (31.3%) had at least 1 postoperative AE within 3 months. Overall, 159 patients (42.5%) experienced AEs. The readmission rate was significantly higher in patients who experienced AEs (Any AE: 10.1% vs no AE: 1.9% within 3 months; P = <0.001). PROs were not significantly affected by AEs in most questionnaires. Local control, risk of reoperation, mortality, and achieving preplanned margins were similar between AE groups. CONCLUSION: The rate of surgical AEs is considerable in this population. Surgical AEs seem to be associated with a higher number of readmissions, but do not seem to result in significant differences in PROs or in a higher risk of reoperation, mortality, and failure to achieve preplanned margins.

Study Design Narrative Review. Objective The management of spinal tumors requires a multi-disciplinary approach including surgery, radiation, and systemic therapy. Surgical approaches typically require posterior segmental instrumentation to maintain long-term spinal stability. Carbon fiber reinforced pedicle screws (CFRP) are increasingly used in the oncologic setting due to reductions in both imaging artifacts and radiotherapy perturbations compared to titanium implants. We performed a review of the literature and highlight advantages and future areas of study for CFRP. Methods We performed a systematic review of the literature using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and identified 10 articles including 573 patients. Across all studies we reviewed patient demographics, tumor types treated, hardware-related features, complication rates, recurrence, survival, and follow-up. Results Across 10 studies, a total of 1371 screws placed. Surgical and non-surgical complications were reported in 18.3% of patients. Disease progression at the surgical site was detected in 7.3% of patients. There was no significant difference in clinical or hardware complications between CFRP or titanium implants. The most frequent complication attributable to implanted CFRP hardware included screw breakage in 2.4% and loosening in 1.7% of patients, respectively. Conclusion CFRP provide a unique tool in the setting of spinal oncology. With a safety profile comparable to titanium, we review the documented advantages of CFRP posterior implants compared to titanium, while also addressing their current limitations. Additionally, we highlight several areas of future research to identify the optimal patients who will achieve the greatest benefit of CFRP.

Abstract BACKGROUND Liquid biopsy in glioblastoma (GBM) is hindered by insufficient requisite circulating-tumor (ct) and cell-free (cf) DNA in blood due to blood-brain barrier (BBB). This limits the identification of blood-based tumor biomarkers along with biomarker-driven systemic therapies. Real-time image-guided low-intensity focused ultrasound (LIFU) plus IV microbubble oscillators, leads to non-invasive BBB disruption. METHODS LIBERATE is an ongoing, prospective, multi-center, self-controlled, pivotal trial investigating safety and technical efficacy of LIFU-based BBB disruption for increasing blood ctDNA and cfDNA levels in adult GBM patients (aged 18-80 years). Patients with suspected GBM planned for biopsy/resection at ten US centers are being enrolled. Patients with multifocal tumors or tumors arising from deep midline, thalamus, cerebellum, or brainstem are excluded. Patients are administered IV microbubbles for enhanced sonication effects, after which MR-guided BBB disruption using 220kHz LIFU device is performed with real-time acoustic-feedback-control for effective microbubble activation. Pre- and post-LIFU, phlebotomy and MRI brain are performed. Primary study endpoint is defined, per subject, as ratio between their blood cfDNA level 1-hour post-LIFU procedure compared to blood cfDNA pre-procedure. Primary study hypothesis is that BBB disruption leads to ≥2-fold rise in blood cfDNA. Secondary hypothesis is that there exists ≥75% agreement between biomarker pattern in blood cfDNA sample obtained 1-hour post-LIFU and biomarker pattern in tumor tissue obtained later. Trial is powered to evaluate both primary and secondary hypotheses. Based on assumed true agreement rate of 91% and one-sided alpha=0.025, an exact test for binomial proportions provides N=50 with 84% power for secondary hypothesis. Exploratory endpoints include (1) sensitivity of detection of specific somatic mutations in ctDNA from blood collected pre- and post-LIFU, (2) ctDNA estimation in samples collected at 30-minutes, 1-hour, 2-hour, and 3-hour post-LIFU to determine time of greatest yield, (3) correlation of MRI parameters related to grading of BBB disruption and ctDNA-based biomarkers from post-LIFU blood samples. Patient enrollment commenced in 2022 and remains ongoing (NCT05383872).

Abstract BACKGROUND Liquid biopsy in glioblastoma (GBM) is hindered by a lack of requisite circulating tumor (ct) and cell-free (cf) DNA levels in blood due to the blood-brain barrier (BBB). This limits the identification of blood-based tumor biomarkers along with the development and use of biomarker-driven systemic therapies. Real-time image-guided low intensity focused ultrasound (LIFU) combined with intravenously administered microbubble oscillators, leads to non-invasive disruption of the BBB. This trial aims to evaluate the utility of LIFU for boosting blood ctDNA and cfDNA for enhanced liquid biopsy in GBM patients. MATERIAL AND METHODS LIBERATE is an ongoing, prospective, multi-center, self-controlled, pivotal trial evaluating safety and technical efficacy of LIFU-based BBB disruption for increasing blood ctDNA and cfDNA levels in adults, aged 18-80 years with GBM. Patients with suspected GBM planned for tumor biopsy or resection at ten centers in the US are being enrolled. Patients with multifocal tumors or tumors arising from deep midline, thalamus, cerebellum, or brainstem are excluded. Patients are administered IV microbubbles for enhanced sonication effects, after which MR-guided BBB disruption using a 220 kHz LIFU device is performed with real-time acoustic feedback control for effective microbubble activation. Before and after procedure, phlebotomy and MRI brain are performed to evaluate outcomes. Primary study endpoint is defined, per subject, as ratio between their cfDNA level in blood 1-hour post-LIFU procedure compared to cfDNA level in blood pre-procedure. Primary study hypothesis is that BBB disruption with LIFU leads to a ≥2-fold rise in blood cfDNA. The secondary hypothesis is that there exists ≥75% agreement between biomarker pattern in blood cfDNA sample obtained 1-hour post-LIFU and the biomarker pattern in tumor tissue obtained later. The trial has been powered to evaluate both primary and secondary hypotheses. Based on an assumed true agreement rate of 91% and a one-sided alpha of 0.025, an exact test for binomial proportions provides a sample of N = 50 with 84% power for the secondary hypothesis. Exploratory endpoints include (1) sensitivity of detection of known specific somatic mutations in ctDNA from blood samples collected before and after LIFU, (2) estimation of ctDNA levels post-LIFU in samples collected at 30 minutes, 1 hour, 2 hour, and 3 hour to determine the time of greatest yield, (3) correlation of MRI parameters related to grading of BBB disruption and ctDNA-based biomarkers from post-LIFU blood samples. RESULTS Patient enrollment commenced in 2022, and 22 patients have been recruited by 05/2024. CONCLUSION Findings from this trial will be critical to liquid biopsy in GBM (Clinical trial information: NCT05383872).