Spinal Cord Tumor Microenvironment

Establishment of an MRI-based radiomics model for distinguishing between intramedullary spinal cord tumor and tumefactive demyelinating lesion

OBJECTIVE

Differentiating intramedullary spinal cord tumor (IMSCT) from spinal cord tumefactive demyelinating lesion (scTDL) remains challenging with standard diagnostic approaches. This study aims to develop and evaluate the effectiveness of a magnetic resonance imaging (MRI)-based radiomics model for distinguishing scTDL from IMSCT before treatment initiation.

METHODS

A total of 75 patients were analyzed in this retrospective study, comprising 55 with IMSCT and 20 with scTDL. Radiomics features were extracted from T1- and T2-weighted imaging (T1&T2WI) scans upon admission. Ten classification algorithms were employed: logistic regression (LR); naive bayes (NaiveBayes); support vector machine (SVM); k nearest neighbors (KNN); random forest (RF); extra trees (ExtraTrees); eXtreme gradient boosting (XGBoost); light gradient boosting machine (LightGBM); gradient boosting (GradientBoosting); and multi-Layer perceptron (MLP). The performance of the optimal model was then compared to radiologists' assessments.

RESULTS

This study developed 30 predictive models using ten classifiers across two imaging sequences. The MLP model with two sequences (T1&T2WI) emerged as the most effective one, showing superior accuracy in MRI analysis with an area under the curve (AUC) of 0.991 in training and 0.962 in testing. Moreover, statistical analyses highlighted the radiomics model significantly outperformed radiologists' assessments (p < 0.05) in distinguishing between IMSCT and scTDL.

CONCLUSION

We present an MRI-based radiomics model with high diagnostic accuracy in differentiating IMSCT from scTDL. The model's performance was comparable to junior radiologists, highlighting its potential as an effective diagnostic aid in clinical practice.

An adult with recurrent atypical teratoid rhabdoid tumor of the spine

Atypical teratoid rhabdoid tumors (AT/RT) are rare and highly malignant CNS neoplasms primarily affecting children. Adult cases are extremely uncommon, with only approximately 92 reported. Spinal AT/RT in adults is particularly rare. Here, we present the case of a 50-year-old patient diagnosed with AT/RT of the spine. Initially, they were diagnosed and treated for a spinal ependymoma. However, after 10 years, a recurrence was detected through magnetic resonance imaging (MRI) and the tumor was reclassified as AT/RT. We discuss the significance of SMARCB1 gene mutations in diagnosing AT/RT and describe our unique treatment approach involving surgery, radiation and anti-PD1 therapy in this patient.

Analyses of DNA Methylation Profiling in the Diagnosis of Intramedullary Astrocytomas

Intramedullary astrocytomas (IMAs) consist of a heterogeneous group of rare central nervous system (CNS) tumors associated with variable outcomes. A DNA methylation-based classification approach has recently emerged as a powerful tool to further classify CNS tumors. However, no DNA methylation-related studies specifically addressing to IMAs have been performed yet. In the present study, we analyzed 16 IMA samples subjected to morphological and molecular analyses, including DNA methylation profiling. Among the 16 samples, only 3 cases were classified in a reference methylation class (MC) with the recommended calibrated score (≥0.9). The remaining cases were either considered “no-match” cases (calibrated score <0.3, n = 7) or were classified with low calibrated scores (ranging from 0.32 to 0.53, n = 6), including inconsistent classification. To obtain a more comprehensive tool for pathologists, we used different unsupervised analyses of DNA methylation profiles, including our data and those from the Heidelberg reference cohort. Even though our cohort included only 16 cases, hypotheses regarding IMA-specific classification were underlined; a potential specific MC of PA_SPINE was identified and high-grade IMAs, probably consisting of H3K27M wild-type IMAs, were mainly associated with ANA_PA MC. These hypotheses strongly suggest that a specific classification for IMAs has to be investigated.

Simultaneous 3D Visualization of the Microvascular and Neural Network in Mouse Spinal Cord Using Synchrotron Radiation Micro-Computed Tomography

Effective methods for visualizing neurovascular morphology are essential for understanding the normal spinal cord and the morphological alterations associated with diseases. However, ideal techniques for simultaneously imaging neurovascular structure in a broad region of a specimen are still lacking. In this study, we combined Golgi staining with angiography and synchrotron radiation micro-computed tomography (SRμCT) to visualize the 3D neurovascular network in the mouse spinal cord. Using our method, the 3D neurons, nerve fibers, and vasculature in a broad region could be visualized in the same image at cellular resolution without destructive sectioning. Besides, we found that the 3D morphology of neurons, nerve fiber tracts, and vasculature visualized by SRμCT were highly consistent with that visualized using the histological method. Moreover, the 3D neurovascular structure could be quantitatively evaluated by the combined methodology. The method shown here will be useful in fundamental neuroscience studies.

Surgical treatment of intramedullary spinal cord metastases: functional outcome and complications-a multicenter study

Intramedullary spinal cord metastasis (ISCM) is a rare event in the course of advanced malignancy. Management of these lesions remains controversial. Recently, surgery for ISCM has been advocated for selected patients. We performed a retrospective analysis of the clinical course, complications, and outcome of 30 patients surgically treated for ISCM. Patients' age, histopathological diagnoses of primary cancer, tumor size, spinal location, and extramedullary tumor dissemination were collected. Preoperative functional status, pre- and postoperative neurological status, and extent of the tumor resection were also analyzed. Predominant tumor location was thoracic, followed by cervical and conus medullaris. Lung cancer constituted the majority of primary malignancies. In 9 cases, one of the indications for spinal surgery was to obtain a histopathological diagnosis. On admission, all patients presented with neurological symptoms suggestive of myelopathy. After surgery, 18 patients exhibited improvement of symptoms in terms of pain relief and partial recovery of motor and/or sensory deficits; 6 patients were unchanged, while 6 patients exhibited postoperative deterioration. Median survival time after surgery was 9.9 months. Age > 70 years old, presence of systemic metastases, preoperative neurological non functional status, and lung cancer as primary tumor were all factors associated with a worse survival prognosis. This study did not show a clear survival difference between gross total and subtotal ISCM tumor resection. Patients who underwent gross total resection had a worse functional outcome with respect to patients with only partial resection. Gross total resection with low morbidity must be the surgical target, but when not possible, subtotal resection and adjuvant therapy are a valid therapeutic option.

A reproduceable in situ xenograft model of spinal glioma

BACKGROUND

Spinal glioma is a nervous system tumor that tends to relapse and has no specific prognostic molecular biomarkers. Thus, a stable and reproduceable animal research model of spinal glioma is urgently needed.

NEW METHOD

We established a new in situ tumor xenograft model of spinal glioma using nude mice. In this study, we implanted tumors into the cervical spinal cord of nude mice to mimic the pathological characteristics of the original tumors.

RESULTS

Through anatomical experiments, we found that the cervical lamina of mice was thinner, the intervertebral space was much wider, and the adhesion muscles were more easily separated. According to the examination of spinal cord sections, the best puncture point we identified was located 0.9 mm lateral to the posterior median line at the level of the line between the midpoints of the scapulae and at a depth of 0.9 mm. In the nude mouse xenograft experiment, the implanted tumor tissue retained the pathological characteristics of the original tumor.

COMPARISON WITH EXISTING METHOD(S)

This model used the cervical spinal cord as the puncture site and patient-derived primary tumor cells, which has never been performed before. Tumor cells could be injected directly without damaging the lamina. Thus, we could reduce the risk of man-made spinal cord injury and infection and avoid destroying the stability and integrity of the spine.

CONCLUSIONS

This study established a stable and reliable animal model of spinal glioma for further molecular research and targeted therapy development.