Establishment and validation of an interactive artificial intelligence platform to predict postoperative ambulatory status for patients with metastatic spinal disease: a multicenter analysis.

BACKGROUND: Identification of patients with high-risk of experiencing inability to walk after surgery is important for surgeons to make therapeutic strategies for patients with metastatic spinal disease. However, there is a lack of clinical tool to assess postoperative ambulatory status for those patients. The emergence of artificial intelligence (AI) brings a promising opportunity to develop accurate prediction models. METHODS: This study collected 455 patients with metastatic spinal disease who underwent posterior decompressive surgery at three tertiary medical institutions. Of these, 220 patients were collected from one medical institution to form the model derivation cohort, while 89 and 146 patients were collected from two other medical institutions to form the external validation cohorts 1 and 2, respectively. Patients in the model derivation cohort were used to develop and internally validate models. To establish the interactive AI platform, machine learning techniques were used to develop prediction models, including logistic regression (LR), decision tree (DT), random forest (RF), extreme gradient boosting machine (eXGBM), support vector machine (SVM), and neural network (NN). Furthermore, to enhance the resilience of the study's model, an ensemble machine learning approach was employed using a soft-voting method by combining the results of the above six algorithms. A scoring system incorporating 10 evaluation metrics was used to comprehensively assess the prediction performance of the developed models. The scoring system had a total score of 0 to 60, with higher scores denoting better prediction performance. An interactive AI platform was further deployed via Streamlit. The prediction performance was compared between medical experts and the AI platform in assessing the risk of experiencing postoperative inability to walk among patients with metastatic spinal disease. RESULTS: Among all developed models, the ensemble model outperformed the six other models with the highest score of 57, followed by the eXGBM model (54), SVM model (50), and NN model (50). The ensemble model had the best performance in accuracy and calibration slope, and the second-best performance in precise, recall, specificity, area under the curve (AUC), Brier score, and log loss. The scores of the LR model, RF model, and DT model were 39, 46, and 26, respectively. External validation demonstrated that the ensemble model had an AUC value of 0.873 (95% CI: 0.809-0.936) in the external validation cohort 1 and 0.924 (95% CI: 0.890-0.959) in the external validation cohort 2. In the new ensemble machine learning model excluding the feature of the number of comorbidities, the AUC value was still as high as 0.916 (95% CI: 0.863-0.969). In addition, the AUC values of the new model were 0.880 (95% CI: 0.819-0.940) in the external validation cohort 1 and 0.922 (95% CI: 0.887-0.958) in the external validation cohort 2, indicating favorable generalization of the model. The interactive AI platform was further deployed online based on the final machine learning model, and it was available at https://postoperativeambulatory-izpdr6gsxxwhitr8fubutd.streamlit.app/ . By using the AI platform, researchers were able to obtain the individual predicted risk of postoperative inability to walk, gain insights into the key factors influencing the outcome, and find the stratified therapeutic recommendations. The AUC value obtained from the AI platform was significantly higher than the average AUC value achieved by the medical experts ( P <0.001), denoting that the AI platform obviously outperformed the individual medical experts. CONCLUSIONS: The study successfully develops and validates an interactive AI platform for evaluating the risk of postoperative loss of ambulatory ability in patients with metastatic spinal disease. This AI platform has the potential to serve as a valuable model for guiding healthcare professionals in implementing surgical plans and ultimately enhancing patient outcomes.

Development and validation of a web-based artificial intelligence prediction model to assess massive intraoperative blood loss for metastatic spinal disease using machine learning techniques.

BACKGROUND CONTEXT: Intraoperative blood loss is a significant concern in patients with metastatic spinal disease. Early identification of patients at high risk of experiencing massive intraoperative blood loss is crucial as it allows for the development of appropriate surgical plans and facilitates timely interventions. However, accurate prediction of intraoperative blood loss remains limited based on prior studies. PURPOSE: The purpose of this study was to develop and validate a web-based artificial intelligence (AI) model to predict massive intraoperative blood loss during surgery for metastatic spinal disease. STUDY DESIGN/SETTING: An observational cohort study. PATIENT SAMPLE: Two hundred seventy-six patients with metastatic spinal tumors undergoing decompressive surgery from two hospitals were included for analysis. Of these, 200 patients were assigned to the derivation cohort for model development and internal validation, while the remaining 76 were allocated to the external validation cohort. OUTCOME MEASURES: The primary outcome was massive intraoperative blood loss defined as an estimated blood loss of 2,500 cc or more. METHODS: Data on patients' demographics, tumor conditions, oncological therapies, surgical strategies, and laboratory examinations were collected in the derivation cohort. SMOTETomek resampling (which is a combination of Synthetic Minority Oversampling Technique and Tomek Links Undersampling) was performed to balance the classes of the dataset and obtain an expanded dataset. The patients were randomly divided into two groups in a proportion of 7:3, with the most used for model development and the remaining for internal validation. External validation was performed in another cohort of 76 patients with metastatic spinal tumors undergoing decompressive surgery from a teaching hospital. The logistic regression (LR) model, and five machine learning models, including K-Nearest Neighbor (KNN), Decision Tree (DT), XGBoosting Machine (XGBM), Random Forest (RF), and Support Vector Machine (SVM), were used to develop prediction models. Model prediction performance was evaluated using area under the curve (AUC), recall, specificity, F1 score, Brier score, and log loss. A scoring system incorporating 10 evaluation metrics was developed to comprehensively evaluate the prediction performance. RESULTS: The incidence of massive intraoperative blood loss was 23.50% (47/200). The model features were comprised of five clinical variables, including tumor type, smoking status, Eastern Cooperative Oncology Group (ECOG) score, surgical process, and preoperative platelet level. The XGBM model performed the best in AUC (0.857 [95% CI: 0.827, 0.877]), accuracy (0.771), recall (0.854), F1 score (0.787), Brier score (0.150), and log loss (0.461), and the RF model ranked second in AUC (0.826 [95% CI: 0.793, 0.861]) and precise (0.705), whereas the AUC of the LR model was only 0.710 (95% CI: 0.665, 0.771), the accuracy was 0.627, the recall was 0.610, and the F1 score was 0.617. According to the scoring system, the XGBM model obtained the highest total score of 55, which signifies the best predictive performance among the evaluated models. External validation showed that the AUC of the XGBM model was also up to 0.809 (95% CI: 0.778, 0.860) and the accuracy was 0.733. The XGBM model, was further deployed online, and can be freely accessed at https://starxueshu-massivebloodloss-main-iudy71.streamlit.app/. CONCLUSIONS: The XGBM model may be a useful AI tool to assess the risk of intraoperative blood loss in patients with metastatic spinal disease undergoing decompressive surgery.

Mini-open compared with the trans-tubular approach in patients with spinal metastases underwent decompression surgery---a retrospective cohort study.

BACKGROUND: This study aimed to evaluate the perioperative safety and efficacy of the Mini-open and trans-tubular approach in patients with spinal metastases who underwent decompression surgery. METHODS: 37 consecutive patients with spinal metastases who underwent decompression surgery through a Mini-open or trans-tubular approach were retrospectively reviewed between June 2017 and June 2022. Thirty-four patients were included in this study. 19 underwent decompression surgery through the Mini-open approach, and 15 underwent the Trans-tubular approach. T-test and chi-square test were used to evaluate the difference between baseline data and primary and secondary outcomes. RESULTS: Baseline characteristics did not differ significantly between Trans-tubular and Mini-open groups except for the Ambulatory status (P < 0.001). There was no significant difference in blood loss between the two groups (P = 0.061). Operative time, intraoperative blood transfusion, intraoperative complication (dural tear), and postoperative hospitalization were comparable in the two groups (P > 0.05). The trans-tubular group had significantly less amount of postoperative drainage (133.5 ± 30.9 ml vs. 364.5 ± 64.2 ml, p = 0.003), and the time of drainage (3.1 ± 0.2 days vs. 4.6 ± 0.5 days, p = 0.019) compared with Mini-open group (P < 0.05). Sub-group analysis showed that for patients with hypo-vascular tumors, the Trans-tubular group had significantly less blood loss than the Mini-open group (951.1 ± 171.7 ml vs. 1599.1 ± 105.7 ml, P = 0.026). CONCLUSIONS: Decompression through Mini-open or Trans-tubular was safe and effective for patients with spinal metastases. The trans-tubular approach might be more suitable for patients with hypo-vascular tumors.

Manual Homogenization Improves the Sensitivity of Microbiological Culture for Patients with Pyogenic Spondylitis.

Objective: This study aimed to investigate the effects of manual homogenization on the sensitivity of microbiological culture for patients with pyogenic spondylitis. Methods: From October 2018 to March 2021, patients undergoing fluoroscopy-guided biopsy or open debridement due to pyogenic spondylitis were recruited. Their demographic data and baseline characteristics were recorded. Tissue samples were obtained through fluoroscopy-guided biopsy or open debridement. Tissue samples were divided into three parts: manual homogenization (MH), manual mixture (MM), and pathological examination. Sterile normal saline was set as the negative control to exclude false-positive culture results. The Chi-square test was used to detect the difference of microbiological culture results. Results: Twenty-four consecutive patients (33 tissue cultures) with pyogenic spondylitis treated in our department between October 2018 and March 2021 were recruited in this study. The average age was 61.7±3.2 years old and 10 patients were female. The MH group had a significantly higher positive rate compared with the MM group in aerobic conditions: 78.8% (26 isolates) vs 54.5% (18 isolates), P=0.037 and anaerobic condition: 63.6% (21 isolates) vs 39.4% (13 isolates), P=0.049. The results of subgroup analyses showed that MH could improve the culture sensitivity for patients with previous antibiotics use and without paravertebral abscesses but not reach a significant level on statistics. Conclusion: Based on the present study, manual homogenization could improve the sensitivity of microbiological cultures for patients with pyogenic spondylitis.

Risk factors for predicting cement leakage in percutaneous vertebroplasty for spinal metastases.

BACKGROUND: The study aimed to identify the risk factors of cement leakage following percutaneous vertebroplasty for spinal metastases. METHODS: 230 consecutive patients with 530 vertebrae were retrospectively reviewed. Characteristics including age, primary cancer, location, pathological fracture, the integrity of the posterior wall, and the volume of bone cement were considered as potential risk factors. Cement leakage was evaluated by postoperative imaging examination and classified into three subtypes with different potential sequelae: spinal canal leakage, intravascular leakage around vertebrae, intradiscal and paravertebral leakage. Univariate and multivariate analyses were used to assess the risk factors. RESULTS: Leakage was detected in 185 vertebrae (34.9%), 18.3% for intradiscal and paravertebral, 13.2% for intravascular around vertebrae, and 7.0% for spinal canal. Multivariate analysis showed that incomplete posterior wall (P = 0.001) and breast cancer (P = 0.015) were strong predictive factors for spinal canal leakage, incomplete posterior wall (P = 0.024) was for intravascular leakage around vertebrae, thoracic (P = 0.010) and pathological fracture (P = 0.000) were for intradiscal and paravertebral leakage. CONCLUSIONS: Our findings suggest that cement leakage is common following percutaneous vertebroplasty for spinal metastases. The incomplete posterior wall is an unfavourable factor for intravascular leakage around vertebrae. Vertebrae with incomplete posterior wall and breast cancer metastases are more likely to develop spinal canal leakage.

Comparison of Minimally Invasive Tubular Surgery with Conventional Surgery in the Treatment of Thoracolumbar Metastasis.

BACKGROUND: This study aimed to evaluate the perioperative safety and efficacy of minimally invasive tubular surgery for patients with spinal metastasis. METHODS: A total of 161 consecutive patients with spinal metastasis between June 2017 and June 2020 were retrospectively reviewed. A total of 36 patients were included in this study, 14 patients underwent minimally invasive tubular surgery (M), and 22 patients underwent conventional surgery (C). T-test and chi-square tests were used to evaluate demographic and perioperative data differences between the two groups. RESULTS: Baseline characteristics did not differ significantly between M and C groups except for the SINS (p=0.002) and preoperative Alb (p=0.026). There was no significant difference in operative time and complications between M and C groups (p<0.05). The M group had less mean blood loss than the C group (1275 vs 718mL, p=0.045). Blood transfusion was comparable between the two groups (p<0.05). The mean amount and drainage time were lower than the C group (141 vs 873mL, p<0.001; 3.1 vs 7.0 days, P<0.001). The mean postoperative hospitalization of the M group was 8.8 days, which was lower than the C group (11.3 days, p=0.045). Sub-analysis showed that for patients with hyper-vascular tumor, the M group had less mean amount and time of drainage compared with the C group (p<0.05); for patients with hypo-vascular tumor, the mean blood loss and amount of blood transfusion were also reduced in M group (p<0.05). The mean blood loss and drainage time of patients with hypo-vascular tumors were less than patients with hyper-vascular tumors in the M group (p<0.05). CONCLUSION: In selected cases, minimally invasive tubular surgery is safe and effective for patients with spinal metastasis. Patients with hypo-vascular tumors were more suitable for this technique with less blood loss, fewer blood transfusions, minor drainage, and shorter postoperative hospitalization.

Risk factors of total blood loss in the posterior surgery for patients with thoracolumbar metastasis.

BACKGROUND: Blood loss in posterior surgery patients with thoracolumbar metastasis posed a significant challenge to surgeons. This study aimed to explore the risk factors of blood loss in posterior surgery for patients with thoracolumbar metastasis. METHODS: One hundred forty-two patients were retrospectively reviewed. Their baseline characteristics were recorded. The Gross equation was used to calculate blood loss on a surgical day. Multivariate linear regression was used to analyze the risk factors. RESULTS: Mean blood loss of 142 patients were 2055 ± 94 ml. Hypervascular primary tumor (kidney, thyroid and liver) (P = 0.017), wide or marginal excision (en-bloc: P = 0.001), metastasis at the lumbar spine (P = 0.033), and the presence of extraosseous tumor mass (P = 0.012) were independent risk factors of blood loss in the posterior surgery. Sub-analysis showed that wide or marginal excision (en-bloc: P < 0.001) and metastasis at lumbar spine (P = 0.007) were associated with blood loss for patients with non-hyper vascular primary tumors. Wide or marginal excision (piece-meal: P = 0.014) and the presence of an extraosseous tumor mass (P = 0.034) were associated with blood loss for patients with hypervascular primary tumors. CONCLUSION: Hypervascular primary tumor (kidney, thyroid, and liver) was an independent risk factor of blood loss in the posterior surgery. The presence of extraosseous tumor mass and wide or marginal excision (piece-meal) were independent risk factors for patients with hypervascular primary tumors. Metastasis at the lumbar spine and wide or marginal excision (en-bloc) were independent risk factors for patients with non-hyper vascular primary tumors.

A Nomogram to Predict Intra-Spinal Canal Cement Leakage Among Elderly Patients with Spine Metastases: An Internal-Validated Model.

PURPOSE: This study aimed to assess the risk variables for predicting intra-spinal canal cement leakage, especially among elderly patients with spine metastases after being treated with percutaneous vertebroplasty (PVP). Furthermore, we proposed and validated a nomogram to stratify risks of intra-spinal canal cement leakage. METHODS: We retrospectively analyzed 163 elderly patients (age ≧65 years) with spine metastases who underwent PVP. Patients were randomly divided into a training cohort (n=100) and a validation cohort (n=63). The multivariate logistic regression analysis was used to screen potential risk variables in the training cohort. Significant risk variables were included in the nomogram, and the nomogram was developed according to the estimates of the each included variable. The predictive effectiveness of the nomogram was validated using discrimination and calibration performance. RESULTS: The overall prevalence of intra-spinal canal cement leakage was 9.82% (16/163). In the training cohort, female patients (14.71%, 5/34) showed a higher rate of intra-spinal canal cement leakage as compared with male patients (4.55%, 3/66). The nomogram consisted of sex, cortical osteolytic destruction in posterior wall, and load-bearing lines of spine. The nomogram had acceptable discrimination, with the area under the receiver operating characteristic (AUROC) of 0.75 in the training cohort, 0.64 in the validation cohort, and 0.69 in the entire cohort, and also showed favorable calibration based on the goodness-of-fit test. According to the nomogram, three risk groups were developed: the low risk group had an actual probability of 7.03%, the medium risk group was 11.54%, and high risk group was 44.44%. The difference between the three groups was significant (P ˂ 0.01). CONCLUSION: Intra-spinal canal cement leakage after PVP is not scarce among elderly patients. We proposed and internally validated a nomogram that is capable of calculating the risk of intra-spinal canal cement leakage among elderly patients with spine metastases. Careful surgical plan should be conducted among patients with a high risk of developing intra-spinal canal cement leakage.

Clinicopathological characteristics and prognostic risk factors of breast cancer patients with bone metastasis.

BACKGROUND: A retrospective study was performed to summarize the clinicopathological characteristics of breast cancer patients with bone metastasis, to clarify the metastasis sites, and to explore the risk factors affecting prognosis. METHODS: Breast cancer patients with bone metastasis diagnosed in our hospital from January 2008 to January 2019 were included. Through follow-up by telephone call or return visit, the metastasis sites and clinicopathological characteristics were summarized. The risk factors influencing prognosis were analyzed by univariate and multivariate regression analyses. RESULTS: Multifocal bone metastases were dominant in the 150 patients, and the metastatic rates in the spine, chest, pelvis, limbs, and skull were 75.3%, 74.0%, 56.0%, 46.7%, and 28.7%, respectively, with significant differences (P<0.01). Kaplan-Meier univariate analysis showed that age, menstrual status, number of metastatic lymph nodes, clinical stage, endocrine therapy, alkaline phosphatase level, visceral metastasis, and number of bone metastasis sites affected the overall survival. Cox multivariate regression analysis revealed that endocrine therapy, number of metastatic lymph nodes, visceral metastasis, number of bone metastasis sites, and c-erbB-2 expression were independent prognostic factors. CONCLUSIONS: Middle-aged and elderly patients with breast cancer, mainly aged 40-60 years old, are prone to bone metastasis. The incidence rate of bone metastasis is high within 3 years after surgery, involving the spine, chest, pelvis, limbs, and skull in descending order. The number of metastatic lymph nodes, endocrine therapy, visceral metastasis, number of bone metastasis lesions at the first onset, and c-erbB-2 expression are independent prognostic factors influencing the survival rate of breast cancer patients with bone metastasis.

Effect of the Timing of Surgery on Neurological Recovery for Patients with Incomplete Paraplegia Caused by Metastatic Spinal Cord Compression.

OBJECTIVE: This study aimed to investigate the effect of timing of surgery on neurological recovery for patients with metastatic spinal cord compression (MSCC). METHODS: According to the timing of surgery, 75 patients with incomplete paraplegia caused by MSCC were assigned to 3 groups: within 3 days (group A), between 4 days and 7 days (group B), and after 7 days (group C). T-test, one-way ANOVA, Mann-Whitney U-test, and Chi-square test were used to evaluate the difference in the improvement of American Spinal Injury Association Impairment Scale (AIS) and ambulatory status, the incidence of perioperative complications, surgical site infection, and the length of hospital stay between 3 groups. RESULTS: Patients with incomplete paraplegia treated in our department had an average of 17.4±1.8 days delayed and most occurred before hospitalization (4.0±0.4 vs 13.2±1.8, P<0.001). There was no significant difference in the AIS improvement between patients with different pre-op AIS. The timing of surgery was significantly correlated with AIS improvement (correlation coefficient=-0.257, P=0.019). Sub-analysis showed that patients who underwent surgery within 7 days (group A and group B) had significantly better AIS improvement compared with group C (improved at least 1 grade, P=0.043; improved more than 1 grade, P=0.039) and the surgery timing was more important for patients with AIS B and C. The timing of surgery was significantly correlated with the length of hospital stay (correlation coefficient=0.335, P=0.003). Patients of group C had the longest length of hospital stay (P=0.002). The incidence of perioperative complications and surgical site infection did not differ significantly between the 3 groups. CONCLUSION: Delay surgery was common in incomplete paraplegia patients with MSCC. Patients with AIS B and C who underwent surgery within 7 days had better AIS improvement.

Prediction of early vascular cement leakage following percutaneous vertebroplasty in spine metastases: the Peking University First Hospital Score (PUFHS).

BACKGROUND: Cement leakage into venous blood posed significant challenge to surgeons. The aim of the study was to create a Peking University First Hospital Score (PUFHS) which could evaluate the probability of vascular cement leakage among spine metastases patients following percutaneous vertebroplasty. METHODS: The study retrospectively enrolled 272 spine metastases patients treated with percutaneous vertebroplasty. We randomly extracted all enrolled patients as the training or validation group and baseline characteristic comparison was assessed between the two groups. Creation of the PUFHS was performed in the training group and validation of the PUFHS was performed in the validation group. RESULTS: Of all the 272 patients, the total number of included vertebrae was 632 and the median treated levels were 2 per patient. Vascular cement leakage occurred in 26.47% (72/272) of patients. The baseline characteristics were comparable between the two groups (P > 0.05). Three risk predictors (primary cancer types, number of treated vertebrae levels, and vertebrae collapse) were included in the PUFHS. The area under the receiver operating characteristic curve (AUROC) of the PUFHS was 0.71 in the training group and 0.69 in the validation group. The corresponding correct classification rates were 73.0 and 70.1%, respectively. The calibration slope was 0.78 (95% confidence interval[CI]: 0.45-1.10) in the training group and 1.10 (95% CI: 0.73-1.46) in the validation group. The corresponding intercepts were 0.06 (95% CI: - 0.04-0.17) and - 0.0079 (95% CI: - 0.11-0.092), respectively. CONCLUSIONS: Vascular cement leakage is common among spine metastases after percutaneous vertebroplasty. The PUFHS can calculate the probability of vascular cement leakage, which can be a useful tool to inform surgeons about vascular cement leakage risk in advance.

Epidemiology and detection of cement leakage in patients with spine metastases treated with percutaneous vertebroplasty: A 10-year observational study.

OBJECTIVES: To investigate the epidemiology of cement leaks and further develop an algorithm to detect the high risk of cement leaks among advanced cancer patients with metastatic spinal disease treated with percutaneous vertebroplasty. METHODS: This study retrospectively analyzed 309 patients with metastatic spinal disease treated with percutaneous vertebroplasty. Patients were randomly divided into a training group and a validation group. In the training group, 13 potential characteristics were analyzed for their abilities to predict cement leaks. Discal cement leakage and paravertebral cement leakage were excluded from the analysis. Those characteristics identified as having significant predictive value were used to develop a predictive algorithm. Internal validation of the algorithm was performed based on discrimination and calibration qualities. RESULTS: Overall, cement leaks occurred in 61.17% (189/309) patients. Among the 13 characteristics analyzed, younger age (P = 0.03), extravertebral bone metastases (P = 0.02), increased number of treated vertebrae levels (P < 0.01), and cortical osteolytic destruction in the posterior wall (P = 0.01) were included in the algorithm. This algorithm generates a score between 0 and 16 points, with higher scores indicating a higher risk of cement leakage. The area under the receiver operating characteristic curve (AUROC) value for the algorithm was 0.75 in the training group and 0.69 in the validation group. The mean correct classification rates for the training and validation groups were 73.5% and 64.9%, respectively, and the corresponding P-values of the goodness-of-fit test were 0.70 and 0.50. CONCLUSIONS: Cement leaks are common in patients with metastatic spinal disease treated with percutaneous vertebroplasty. The present study proposed and internally validated an algorithm that can be used to screen patients at high risk of cement leakage.

Cisplatin-resistant osteosarcoma cell-derived exosomes confer cisplatin resistance to recipient cells in an exosomal circ_103801-dependent manner.

Studies have shown that exosomes can mediate the chemoresistance of drug-resistant cells by transmitting circular RNAs (circRNAs). However, the role of exosome-derived hsa_circ_103801 (exosomal hsa_circ_103801) in osteosarcoma (OS) remains unclear. The level of hsa_circ_103801 was upregulated in the serum exosomes from patients with OS, and OS patients with high hsa_circRNA_103801 expression had a shorter survival time relative to patients with low hsa_circ_103801 expression. The expression of hsa_circ_103801 was upregulated in cisplatin-resistant MG63 (MG63/CDDP) cells compared with that in MG63 cells. In addition, hsa_circ_103801 was highly enriched in exosomes derived from CDDP-resistant OS cells and could be delivered to MG63 and U2OS cells through exosomes. Exosomes derived from CDDP-resistant cells were shown to reduce the sensitivity of MG63 and U2OS cells to CDDP, inhibit apoptosis, and increase the expression of multidrug resistance-associated protein 1 and P-glycoprotein. Moreover, exosomal hsa_circ_103801 could strengthen the promotive effect of exosomes on the chemoresistance of MG63 and U2OS cells to CDDP. Hence, serum exosomal hsa_circ_103801 may serve as an effective prognostic biomarker for OS, and exosomal hsa_circ_103801 could be a potential target for overcoming OS chemoresistance.

Scoring Algorithms for Predicting Survival Prognosis in Patients With Metastatic Spinal Disease: The Current Status and Future Directions.

Various survival scoring systems have been developed to help surgeons select the best candidates for appropriate therapies in patients with metastatic spinal disease. This study aims to discuss the current status and future directions of scoring systems for the prediction of survival prognosis in these patients. The search terms "spine metastases," "metastatic spinal disease," and "metastatic spinal cord compression" were combined with "survival prognosis," "scoring system," and "score" to elicit relevant literatures in PubMed and Embase databases. As a result, 159 articles were selected from PubMed, and 246 articles were extracted from Embase. After reviewing each article, we carefully included and analyzed 74 articles about the development and evaluation of scoring systems for predicting survival prognosis in spine metastases. In this review, those scoring systems were stratified into the historic scoring systems and the modern scoring systems on the basis of the proposed time. The historic scoring systems, including the original/revised Tokuhashi scoring system, the Bauer scoring system, the Tomita scoring system, and the Linden scoring system, and the modern scoring systems, such as the Lei scoring system, the Bartels scoring system, the Mizumoto scoring system, the Bollen scoring system, the Rades scoring system, Oswestry Spinal Risk Index, and the Choi risk calculator, were introduced and discussed in this review. Besides, the clinical effectiveness and pitfalls of the existing systems and the future directions of the next generation of scoring systems were also addressed and discussed. We recommended these scoring systems as preferable reference tools to help doctors to select surgical candidates. In patients with long-term life expectancy, radical surgery, such as wide or marginal excision, can be considered in patients with neurological deficits, spine instability, or severe back pain. Besides, with the advancement and improvement of medical technologies, surgical procedures are changing, which can affect surgical indications such as vertebroplasty, minimal invasive surgery, and percutaneous stabilization, which can also be used in patients with spine instability or severe back pain, and do not require much recovery; hence, they can even be used in patients with relative short-term life expectancy. However, the decision about the treatment of patients with metastatic spinal disease is so complicated and should never rely on prognostic scores alone. The final therapeutic decision should be made by interdisciplinary corporations of oncologists, radiologists, and spinal surgeons. Besides, individual intentions should be respected.

The First Algorithm Calculating Cement Injection Volumes in Patients with Spine Metastases Treated with Percutaneous Vertebroplasty.

PURPOSE: This study aims to develop an algorithm to predict cement injection volumes in patients with spine metastases treated with percutaneous vertebroplasty (PVP). Risk factors were also analyzed for intra-spinal canal cement leakages. PATIENTS AND METHODS: A retrospective analysis of 584 vertebrae in 251 patients. Patients and vertebrae were divided into three groups based on grades of tumor invasion to the spinal cord. Patients with the complete posterior wall of vertebrae were classified into group A, patients without the complete posterior wall of vertebrae but with normal Dural sac were classified into group B, and patients with deformation of the Dural sac but without neurological symptom were classified into group C. We systematically reviewed demographic data, clinical parameters, radiology features, and cement leakages among the three groups. The multiple linear regressions were used to screen potential risk factors and develop the algorithm to predict injected cement volumes in vertebrae. Significant factors were included in the algorithm. Potential risk factors for intra-spinal canal cement leakage were analyzed using the multiple logistic regressions. RESULTS: In the study, 17.1% (100/584) of vertebrae occurred cement leakages. Vertebrae in group C (28.6%, 8/28) had the highest cement leakage rate than patients in group A (14.4%, 61/424) and B (23.5%, 31/132) (P=0.014). Vertebrae in group C (14.3%, 4/28) were also more prone to intra-spinal canal leakages (P=0.003). The multiple logistic analysis showed that the Bilsky scale was significantly associated with intra-spinal canal cement leakages (P<0.001). The multiple linear regression analysis showed that intercept (P<0.001), treated vertebrae level (P<0.001), cortical osteolytic destruction in posterior wall (P<0.001), and Bilsky scale (P=0.014) were significant and those variables were included in the algorithm. The algorithm was Y=3.1627－0.8677×treated vertebrae level－0.6182×cortical osteolytic destruction in the posterior wall－0.2819×Bilsky scale. CONCLUSION: An algorithm is proposed and can be used to calculate cement injection volumes in spine metastases treated with PVP. This algorithm can facilitate surgical planning and guide cement injections. Bilsky scale is an independent risk factor for intra-spinal canal cement leakages. We do not recommend PVP treated in patients with a Bilsky scale of 2 and 3 mainly due to a high rate of intra-spinal canal cement leakages.

Complete remission of a case of high-grade myxofibrosarcoma with lung metastases after modified MAID regimen chemotherapy.

The role of chemotherapy in the treatment of myxofibrosarcoma is unclear. There are no randomized clinical trials evaluating the therapeutic effect of chemotherapy on myxofibrosarcoma. We report, to the best of our knowledge, the first case of myxofibrosarcoma successfully treated with mesna, pirarubicin, ifosfamide and dacarbazine (modified MAID) regimen. The patient achieved complete remission evaluated according to Response Evaluation Criteria in Solid Tumours (RECIST).