Study DesignRetrospective cohort study.ObjectiveSpinal metastases are common in patients with breast cancer, and accurate estimation of postoperative survival is crucial for selecting appropriate candidates for metastasis surgery. This study investigated the association between breast cancer subtype, according to the St. Gallen classification, and survival after surgery for spinal metastases with the aim of improving prognostic assessment and supporting informed patient counselling.MethodsThis study included 110 patients with breast cancer who underwent surgery for spinal metastases identified from the Swedish Spine Register and the Swedish National Quality Register of Breast Cancer. Patients were categorized in terms of the breast cancer subtype according to the St. Gallen classification. Postoperative survival was analysed using Kaplan-Meier estimates and a Cox proportional hazards model.Results: The overall median survival following spinal surgery was 25months (95% CI 19-31), while the median postoperative survival by subtype was 39months (95% CI 28-50) for luminal A patients, 20months (95% CI 9-31) for luminal B patients, and 48months (95% CI 20-76) for luminal B/HER2+ patients. The median survival was not reached for the nonluminal HER2+ group, whereas patients with triple-negative breast cancer had a median survival of only 5months (95% CI 4-6). The St. Gallen subtype was significantly associated with postoperative survival according to univariable (P<0.001) and multivariable analyses (P = 0.011).ConclusionsBreast cancer subtype according to the St. Gallen classification was significantly associated with survival after surgery for spinal metastases. These findings indicate that the St. Gallen classification may serve as a valuable prognostic tool in the metastatic spine setting. Incorporation of molecular subtype information may improve estimation of postoperative survival and support informed patient counselling, expectation management, and individualized surgical decision-making in patients with breast cancer spinal metastases.

Spinal metastases frequently cause debilitating symptoms and require complex surgical management, with postoperative intensive care unit (ICU) admissions representing a major concern. This multicenter study aimed to develop and validate machine learning (ML) models to predict 30-day unplanned ICU admission following metastatic spinal tumor surgery. A total of 642 patients with metastatic spinal disease were enrolled, and 525 from two major institutions were randomly split into derivation (80%) and internal validation (20%) cohorts. External validation was performed using an independent cohort (n=117) from a third medical institution. Six ML algorithms were trained on 11 clinically significant features selected after multicollinearity analysis. In the model development cohort, significant differences were observed between ICU (n=101, 19.2%) and non-ICU groups, with ICU patients demonstrating higher comorbidity burdens, elevated inflammatory markers, and impaired renal function. Among six machine learning models evaluated, the KNN algorithm demonstrated superior predictive performance with the highest discriminative power (Area Under the Curve [AUC]: 0.884), accuracy (82.1%), recall (96.4%), and favorable calibration (Brier score: 0.149). The ANN also performed well, achieving the second-highest AUC (0.847), precision (0.808), and F1 score (0.778), as well as a competitive log loss (0.491). The composite scoring system confirmed KNN and ANN as top performers (total scores: 42 each), but, in the external validation cohort, the KNN model demonstrated significantly superior discriminative ability compared to the ANN model, with an AUC of 0.834 (95% CI: 0.773-0.894) versus 0.741 (95% CI: 0.665-0.816) respectively (Delong test, P<0.001). This study presents validated ML models specifically designed for ICU admission prediction following spinal metastasis surgery, with the KNN model performing satisfactory performance and demonstrating strong potential for clinical implementation.

Author's reply to "Preoperative prediction of early mortality after surgery for spinal metastases".

Letter to "Preoperative prediction of early mortality after surgery for spinal metastases".

Retrospective single-institution cohort study. To evaluate the efficacy of combined intermittent pneumatic compression (IPC) and graduated compression stockings (GCS) versus GCS alone for preventing deep venous thrombosis (DVT) in patients undergoing separation surgery for thoracolumbar metastases. DVT is a significant perioperative complication in spinal metastasis surgery. Mechanical prophylaxis is preferred over chemoprophylaxis due to bleeding risks, but evidence supporting the combined use of IPC and GCS over GCS alone is lacking. From 2018 to 2023, 385 patients undergoing separation surgery were included. Group A (n=184) received GCS alone; Group B (n=201) received combined IPC and GCS. All patients underwent compression duplex ultrasound preoperatively and on postoperative day 7 to detect DVT. Demographic, surgical, and neurological data were collected and compared. Overall DVT incidence was 7.6% in Group A and 6.5% in Group B, with no significant difference (P>0.05). No symptomatic pulmonary embolism occurred. Subgroup analysis of patients with preoperative Frankel A-C scores (severe neurological impairment) showed a significantly lower DVT rate in the combined therapy group (4.8% vs. 8.6%, P<0.05). No difference was found in patients with Frankel D-E scores. Combined IPC and GCS significantly reduced DVT incidence in patients with severe preoperative neurological impairment (Frankel A-C) but not in those with milder deficits (Frankel D-E). Preoperative neurological status should guide DVT prophylaxis strategy in spinal metastasis surgery.

Clinical models for predicting massive intraoperative blood loss (IBL) in spinal metastasis surgery exhibit a systematic, vascularity-dependent bias, underestimating risk in non-hypervascular tumors while overestimating it in hypervascular ones. We aimed to develop and validate an AI model integrating MRI radiomics to reduce this bias and improve risk stratification. This retrospective study included 601 patients who underwent surgery for spinal metastases between January 2016 and December 2022. They were randomized to a development cohort (n=479) and a test cohort (n=122). Clinical characteristics and radiomic features from T1c MRI were used to develop predictive models. Based on internal validation across nine machine learning algorithms, the best-performing model was selected. External testing was performed using an independent cohort of 101 patients to assess generalizability. The primary outcome was defined as massive IBL, with an estimated blood loss of 2,500ml or more. Model performance was evaluated using the area under the curve (AUC), calibration curves, and decision curve analysis. An AI tool was developed to facilitate clinical use. Among the 702 patients included, the combined model integrating MRI radiomics and clinical variables outperformed the clinical model in both internal (AUC: 0.901 [95%CI: 0.8330-0.9690] vs. 0.735 [95%CI: 0.6238-0.8458]) and external validation cohorts (AUC: 0.885 [95%CI: 0.8052-0.9639] vs. 0.604 [95%CI: 0.4355-0.7720]). Subgroup analysis revealed that in non-hypervascular tumors, the combined model significantly increased the sensitivity for identifying massive bleeding (0.85 vs. 0.30, p<0.001). In hypervascular tumors, the specificity was notably enhanced (0.81 vs. 0.55, p<0.001), and meanwhile the false-positive rate was reduced. The use of AI tools also improved the prediction performance of spine surgeons. The model is freely accessible for download at https://github.com/banluqihao/A-predict-tool-for-spinal-metastases-surgery. By integrating MRI radiomics features, our model reduces the systemic biases of clinical-only models that depend on unreliable histological surrogates. This enables more accurate and individualized risk stratification, providing a reliable tool to guide preoperative planning and support more accurate risk stratification for patients with spinal metastases.

Abstract Introduction Accurate pedicle screw placement is critical in spinal tumor and metastasis surgery to ensure stability while minimizing complications. Robot-assisted (RA) techniques have been introduced to improve precision, but their benefits over traditional freehand methods remain uncertain. This study systematically reviews and meta-analyzes the accuracy, safety, and efficiency of RA versus freehand pedicle screw placement in patients with spinal tumors and metastases. Methods A systematic search was conducted across five databases. Studies comparing RA and freehand pedicle screw placement in spinal tumor patients were included. Primary outcomes assessed screw accuracy using the Gertzbein–Robbins (GR) classification, while secondary outcomes included operative time, infection rates, and neurological complications. Data were pooled using odds ratios (OR) and mean differences (MD) with a random-effects model. Results Three studies were included. RA significantly improved screw placement accuracy (GR A: 76.1% vs. 70.3%, OR 1.34, p = 0.023) and reduced minimally misplaced screws (GR B, OR 0.69, p = 0.010). The total percentage of clinically acceptable screws (GR A + B) was comparable between groups (90.9% vs. 90.7%, p = 0.953). RA surgery significantly reduced operative time (MD − 19.24 min, p &lt; 0.01), while infection rates and neurological complications showed no significant differences. Conclusion RA pedicle screw placement showed a trend toward a higher rate of perfectly placed screws (GR A), though this was not confirmed by trial sequential analysis. Overall safety profiles were comparable. Further research is needed to evaluate the long-term outcomes and cost-effectiveness of spinal oncology surgery.

Changes in performance status and predictive factors for poor improvement following surgery for spinal metastasis: a nationwide multicenter prospective cohort study.

Abstract Background Metastatic spinal disease is a common complication of advanced cancer that causes pain, neurological deficits, and mechanical instability. Objective To identify factors associated with survival and motor function after surgery for spinal metastases. Methods We retrospectively analyzed 91 patients treated at a tertiary center (2016–2018). Variables included demographics, primary tumor, extraspinal disease, metastatic epidural spinal cord compression (MESCC), pre/postoperative motor function, procedure, and reoperations. Survival groups were &lt; 60 days, 60 days–12 months, and ≥ 12 months. Associations were tested with univariable statistics (α = 0.05). Results Of 91 patients (56% male; mean age 62.4 ± 10.8 years), 74% underwent decompression and 78% stabilization. The primary tumor was unknown in 18%; among known primaries, multiple myeloma and breast carcinoma predominated. Extraspinal metastases were absent in 77%; MESCC occurred in 68%. Survival was &lt; 60 days in 18%, 60 days–12 months in 29%, and ≥ 12 months in 54%. Solitary and oligometastatic spinal involvement showed numerically better one-year survival compared to multiple lesions, although this difference did not reach statistical significance. Motor function improved in 16%; 14% underwent reoperation. Survival correlated with primary tumor (p = 0.004), extraspinal metastases (p = 0.001), and MESCC (p = 0.003), but not with demographics or surgical variables. In exploratory subgroups, ≥ 80% with breast carcinoma or myeloma survived ≥ 1 year, versus none with gastric or lung carcinoma. Conclusions Postoperative survival chiefly reflected tumor biology and systemic disease extent; MESCC portended poorer prognosis. Our findings suggest that the extent of vertebral involvement may have prognostic implications. Surgery achieved neurological stabilization or improvement in selected patients. Findings may inform multidisciplinary decision-making but need validation in larger cohorts.

ASO Visual Abstract: Beyond the Scalpel-EGFR Mutation Predicts Intraoperative Blood Loss and Transfusion Needs During Lung Cancer-Derived Spinal Metastasis Surgery : Preoperative EGFR Profiling Guides Blood Conservation Strategies.

AimsFrailty has recently been associated with postoperative complications and clinical outcomes in various fields. This study aimed to assess the relationships between frailty and surgical outcomes of palliative surgery for spinal metastases and assess the usefulness of the modified five-item frailty index (mFI-5) in this population.MethodsWe prospectively evaluated 273 patients who underwent spinal metastasis surgery from June 2015 to December 2021. The mFI-5 was used to assess frailty, with a score of 0 defined as non-frailty, 1 as pre-frailty, and 2 or more as frailty. The following variables were assessed: background characteristics, complications (Clavien-Dindo grade 2 or higher), postoperative clinical outcomes, and life expectancy. The clinical outcomes compared between the three groups were the performance status (PS), Barthel index, and EuroQoL five-dimension questionnaire (EQ-5D) at six months postoperatively. A multivariate stepwise logistic regression analysis was performed of variables with values of p < 0.1 on the univariate analysis.ResultsThe overall complication rate was 19% (52/273). The complication rate was significantly higher in the frailty group (p = 0.005), and patients with a greater mFI-5 score tended to have a higher incidence of postoperative complications. The Kaplan-Meier curve showed that the non-frailty group had a significantly longer survival time than the pre-frailty and frailty groups (p < 0.001). Multivariate logistic regression analysis suggested that mFI-5 is not predictive of postoperative complications and improvement of the EQ-5D, while is predictive of improvement of the PS (odds ratio (OR) 4.22) and Barthel index (OR 4.49).ConclusionThe current study suggested that mFI-5 is not predictive of postoperative complications and improvement of the EQ-5D, while is predictive of improvement of the PS and Barthel index. Furthermore, palliative surgery for spinal metastases improved the PS, Barthel index, and EQ-5D, even in patients with frailty.Cite this article: Bone Jt Open 2025;6(10):1199–1207.

Surgical intervention for lung cancer-derived spinal metastasis (LCSM) is frequently associated with significant intraoperative hemorrhage. This prospective cohort study aimed to identify clinical predictors of intraoperative blood loss (IOBL) and red blood cell transfusion requirements in patients undergoing LCSM surgery. Consecutive patients treated surgically for LCSM at a tertiary medical center between January 2017 and August 2024 were prospectively enrolled. Demographic, surgical, and laboratory variables were evaluated, including epidermal growth factor receptor (EGFR) mutation status, metastatic burden, and coagulation profiles. Multivariable linear regression models were used to quantify associations with IOBL and transfusion volume. Among 163 patients, mean IOBL was 765±890 mL, with 54.6% requiring red blood cell transfusions (mean 4.9±2.9 units). Transfused patients demonstrated 3.8-fold greater blood loss than their non-transfused counterparts (1151.7 vs 300.9 mL, p<0.001). Key independent predictors of IOBL included EGFR mutation (β=309.7 mL, p=0.012), lumbar metastases (β=288.7 mL, p=0.038), surgical duration (168.7 mL/h, p<0.001), laminectomy levels (284.3 mL/level, p<0.001), and elevated preoperative international normalized ratio (β=1156.9 mL, p=0.018). Predictors of transfusion volume paralleled these findings, with EGFR mutation (β=1.33 units, p=0.002) and laminectomy levels (β=0.75 units/level, p=0.003) demonstrating dose-dependent relationships. This study identified EGFR mutation as a novel molecular predictor of hemorrhagic risk in LCSM surgery, independent of systemic therapy status. The quantifiable impact of procedural complexity and coagulation dysfunction provides actionable thresholds for preoperative optimization. These findings enable stratified blood management protocols, particularly for EGFR-mutated cohorts requiring multilevel decompression.

Retrospective comparative study. To investigate the impact of institutional function (cancer center and surgical volume for spine surgery) on in-hospital outcomes after surgical treatment for spinal metastasis using a nationwide administrative database. Multidisciplinary approaches to bone metastasis have become common in Japan, especially in cancer centers. However, whether treatment outcomes for spinal metastasis surgery differ by institutional function remains controversial. Data of patients who underwent surgical procedures for spinal metastasis between 2012 and 2020 were extracted from the Diagnosis Procedure Combination database. In-hospital outcomes included in-hospital mortality, 30-day mortality, length of stay until discharge home, postoperative complications, and unfavorable ambulatory status. Univariate and multivariate analyses were performed to investigate the association between cancer center/surgical volume and each outcome while adjusting for potential confounders. A total of 10,320 patients were included in this study. Among them, 5261 patients were treated at cancer centers. The median annual surgical volume for spine surgery was 166 cases. The 30-day mortality was lower in cancer centers than in noncancer centers [odds ratio (OR): 0.841, 95% CI: 0.709-0.999, P=0.0483] and in high-volume hospitals for spine surgery than in low-volume hospitals (OR per 50 cases: 0.958, 95% CI: 0.928-0.990, P=0.0101). The length of stay until discharge home, postoperative complications, and postoperative unfavorable ambulatory status did not differ by cancer center or surgical volume. The short-term mortality was lower in cancer centers or high-volume hospitals, whereas postoperative complications and ambulatory outcomes did not differ by institutional function. A deeper understanding of the multidisciplinary approaches or processes of care adopted at these institutions might be important to deliver similar outcomes in other hospitals to patients with spinal metastasis. Level III.

Prognostic outcomes of spinal metastasis: timing of metastasis presentation matters.

BackgroundBreast cancer is the most common malignancy affecting women, and vertebral metastases are a frequent complication. This study aimed to examine the clinical and anatomical characteristics, therapeutic management, and prognostic factors associated with vertebral metastases from breast carcinomas in patients from south-eastern Tunisia.Materials and methodsThis descriptive cohort analytical study utilized retrospectively collected data and was conducted in the medical oncology and orthopaedic surgery departments at the Gabes University Hospital over a five-year period, from January 2015 to December 2019. Clinical, pathological, and therapeutic data were statistically analysed to identify prognostic factors influencing overall survival.ResultsThe study included 57 patients with a median age of 48 years. Metastases were metachronous in 41 patients (71.9%) and synchronous in 16 (28.1%). Tumours were classified as T4 in 42.1% of study cases. Spinal metastases mainly affected two vertebral levels in 61.4% of patients and involved three vertebrae in 70.2% of cases. Spinal cord compression was the most common complication (24.6%). Extravertebral bone, pulmonary, hepatic, and brain metastases were observed in 80.7%, 43.9%, 49.1%, and 12.3% of patients. Hormone receptors and human epidermal growth factor receptor (HER2) were expressed in 73.3% and 19.3% of cases, respectively. No patients underwent surgery for spinal metastasis. Breast radiotherapy was administered in 52.6% of cases, of which 42.1% targeted spinal metastases. Median survival was 28 months. Overall survival at three and five years was 38.6% and 22.7%, respectively. Significant prognostic factors for overall survival included age (p=0.041) and metastatic disease at diagnosis (p=0.01).ConclusionVertebral bone metastases can compromise the neurological outcomes. However, various systemic and local therapeutic options are available for managing vertebral metastasis. A multidisciplinary approach is essential to optimise strategies and improve prognosis.

Venous thromboembolism (VTE) is a serious complication following spine surgery for metastatic tumors. This study used the US Nationwide Readmissions Database to identify predictors of VTE and its associations with outcomes. Data between 2016 and 2020 were retrospectively reviewed. Patients aged ≥18 years undergoing non-emergency surgery for spinal metastasis were included in the analysis. Multivariable regression analysis was used to assess associations of VTE with in-hospital outcomes and 30- and 90-day readmissions, as well as demographic and clinical factors associated with VTE occurrence during the index admission. In all, 2,706 patients were included in the analysis (mean age 63.6 years; 1,435 [53%] male). Of all patients, 126 (4.7%) developed VTE during the index admission. After adjustment, VTE was significantly associated with an increased risk of in-hospital mortality (adjusted odds ratio [aOR] 5.34; 95% confidence interval [CI] 2.38-11.96) and 30-day readmission (aOR 2.06; 95% CI 1.33-3.19). Delays from admission to surgery (aOR 1.88; 95% CI 1.27-2.79) and a Charlson Comorbidity Index score ≥4 (aOR 3.11; 95% CI 1.60-6.04) were independently associated with an increased risk of VTE. In patients undergoing surgery for spinal metastasis, postoperative VTE is associated with higher in-hospital mortality and 30-day readmission risks. A Charlson Comorbidity Index score ≥4 and delayed surgery are independently associated with greater risk of VTE.

External validation of a machine learning prediction model for massive blood loss during surgery for spinal metastases: a multi-institutional study using 880 patients.

Study DesignLiterature review with clinical recommendations.ObjectiveSpinal metastases represent a late complication of cancer and a major factor in decreased quality of life. The role of surgery for specific indications for spinal metastases is well established. Given the significant morbidity associated with spine surgery in this frail population, efforts are ongoing to decrease the surgical footprint. The objective of this study is to provide the readers with a concise curation of the latest spine literature on reducing the surgical footprint for spine metastases and clinical recommendations for how the practicing clinician should interpret and make use of this evidence.MethodsThe latest spine literature in the topic of reducing the surgical footprint for spine metastases was reviewed and clinical recommendations were formulated. The recommendations are dichotomously graded into strong and conditional based on the integration of scientific methodology and content expert opinion. This opinion considers experience and practical issues such as risks, burdens, costs, patient values, and circumstances.ResultsFour high impact studies were selected for review. The findings suggest that surgery plays a key role in improving patients' quality of life, but incidence of adverse events remains high and hence methods to decrease surgical morbidity are necessary. The integration of radiation into the treatment algorithm allows for less extensive surgical procedures and SBRT should be strongly considered after surgery for spine metastases in appropriate patient populations. Implementation of enhanced recovery after surgery (ERAS) protocols reduce perioperative morbidity for both open and minimally invasive surgeries and should be considered on an institutional level. Utilization of minimally invasive surgical stabilization should be considered as it results in fewer post operative complications, lower infection rates, less blood loss during surgery, and a shorter hospital stay compared to open stabilization of unstable pathology thoracolumbar fractures.ConclusionsThe role and benefits of surgery for metastatic spine disease are well established, yet surgery carries significant risk for adverse events which may negatively affect overall cancer care. Methods for reducing the surgical footprint include incorporation of stereotactic radiation allowing less extensive surgery, implementation of ERAS protocols and utilization of minimally invasive surgical strategies.

Background: Postoperative wound dehiscence is a major complication following spinal metastasis surgery, particularly in patients who receive preoperative radiotherapy or molecular-targeted therapy; however, preventive strategies remain limited. Objective: In this study, we aimed to identify the risk factors for postoperative wound dehiscence and evaluate the clinical utility of a novel curved skin incision (CSI) technique, designed to avoid irradiated areas, in comparison with the conventional midline incision (MI) technique. Methods: Logistic regression analysis was conducted on 107 patients who underwent MI between 2013 and 2018. Based on the results, we developed the CSI technique. Propensity score matching was performed to compare postoperative wound dehiscence in 29 matched pairs of patients treated with either CSI or MI from 2019 to 2021. Results: Preoperative radiotherapy and molecular-targeted therapy were found to be significant risk factors for wound dehiscence. CSI, which circumvents irradiated skin, was associated with a substantially lower rate of wound dehiscence than MI. Conclusions: The CSI technique offers a simple, reproducible, and effective surgical approach to reduce postoperative wound complications in high-risk patients. Its clinical benefit, especially for those with prior radiotherapy, suggests that it may serve as a valuable addition to standard spinal metastasis surgery.

Health- related quality of life after surgery for spinal metastases.