Intracranial Solitary Fibrous Tumor Research Articles

NCOG-49. EFFICACY OF POSTOPERATIVE RADIOTHERAPY AFTER GROSS TOTAL RESECTION FOR INTRACRANIAL SOLITARY FIBROUS TUMORS: A SYSTEMATIC REVIEW AND META-ANALYSIS

Abstract BACKGROUND The efficacy of postoperative radiotherapy (PORT) after gross total resection (GTR) for intracranial solitary fibrous tumors (SFT) remains unclear as previous studies yielded inconsistent results. Therefore, this study aimed to clarify this uncertainty using a comprehensive meta-analysis. By evaluating and synthesizing data from relevant studies, we sought to investigate the role of PORT, as compared with surgery alone, in survival outcomes after GTR of intracranial SFT. METHODS We conducted a systematic literature search, adhering to PRISMA guidelines, using Medline, Embase, and the Cochrane Library to identify relevant literature. The outcomes of interest included progression-free survival (PFS), overall survival (OS), and metastasis-free survival (MFS) at 3, 5, and 10 years, respectively. Differences between the two cohorts (GTR+PORT vs. GTR only) were estimated by calculating the hazard ratios. Results. Twelve studies, including data from 419 patients (PORT, n = 225 vs. surgery only, n = 194), were selected for meta-analysis. Pooled hazard ratios revealed that the PORT cohort showed sustained superiority in both PFS and OS over the surgery-only cohort after GTR of the tumor. These results were consistent with those of a subgroup analysis that focused on grade 2 and 3 intracranial SFT. However, no significant improvement was observed in MFS with PORT addition. Conclusion. The present study underscores the importance of PORT in enhancing the PFS and OS of patients with intracranial SFT after GTR. These findings suggest that PORT should be considered an effective treatment strategy for all patients with intracranial SFT, irrespective of the extent of resection.

Deep learning radiomic nomogram outperforms the clinical model in distinguishing intracranial solitary fibrous tumors from angiomatous meningiomas and can predict patient prognosis.

To evaluate the value of a magnetic resonance imaging (MRI)-based deep learning radiomic nomogram (DLRN) for distinguishing intracranial solitary fibrous tumors (ISFTs) from angiomatous meningioma (AMs) and predicting overall survival (OS) for ISFT patients. In total, 1090 patients from Beijing Tiantan Hospital, Capital Medical University, and 131 from Lanzhou University Second Hospital were categorized as primary cohort (PC) and external validation cohort (EVC), respectively. An MRI-based DLRN was developed in PC to distinguish ISFTs from AMs. We validated the DLRN and compared it with a clinical model (CM) in EVC. In total, 149 ISFT patients were followed up. We carried out Cox regression analysis on DLRN score, clinical characteristics, and histological stratification. Besides, we evaluated the association between independent risk factors and OS in the follow-up patients using Kaplan-Meier curves. The DLRN outperformed CM in distinguishing ISFTs from AMs (area under the curve [95% confidence interval (CI)]: 0.86 [0.84-0.88] for DLRN and 0.70 [0.67-0.72] for CM, p < 0.001) in EVC. Patients with high DLRN score [per 1 increase; hazard ratio (HR) 1.079, 95% CI: 1.009-1.147, p = 0.019] and subtotal resection (STR) [per 1 increase; HR 2.573, 95% CI: 1.337-4.932, p = 0.004] were associated with a shorter OS. A statistically significant difference in OS existed between the high and low DLRN score groups with a cutoff value of 12.19 (p < 0.001). There is also a difference in OS between total excision (GTR) and STR groups (p < 0.001). The proposed DLRN outperforms the CM in distinguishing ISFTs from AMs and can predict OS for ISFT patients. The proposed MRI-based deep learning radiomic nomogramoutperforms the clinical modelin distinguishing ISFTs from AMs and can predict OS of ISFT patients, which could guide the surgical strategy and predict prognosis for patients. Distinguishing ISFTs from AMs based on conventional radiological signs is challenging. The DLRN outperformed the CM in our study. The DLRN can predict OS for ISFT patients.

Intracranial Solitary Fibrous Tumor in a 25-Year-Old Woman

&lt;p&gt;&lt;strong&gt;Introduction:&lt;/strong&gt; Intracranial solitary fibrous tumors (ISFTs) are extremely rare spindle cell tumors originating from dendritic mesenchymal cells expressing CD34 antigens that are usually benign, although malignant transformation had been reported. The knowledge of natural course and prognostic factors of ISFTs is still limited and the tumor is easily misdiagnosed.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Case Presentation:&lt;/strong&gt; An intra-cranial extra-axial tumor tissue resection from a 25-year-old woman was evaluated in the Surgical Pathology Laboratory. Histologic findings (cellular spindle cell tumor with ‘patternless’ pattern, staghorn blood vessels and &amp;lt;5 mitoses per 10 hpf) and immunophenotype (positive for CD34, weakly and focally positive for STAT6) suggested a diagnosis of intracranial solitary fibrous tumor WHO Grade II.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Discussion:&lt;/strong&gt; ISFTs have very low incidence in the CNS and are difficult to distinguish radiologically from meningiomas, thus post operative pathological examination and immunohistochemistry markers evaluations are the mainstay for diagnosis. ISFT is associated with NAB2-STAT6 gene fusion and may exhibits a wide spectrum of histological features. STAT6 immunohistochemistry is considered as one of the most sensitive diagnostic methods, while the evaluation of CD34 expression can be used as alternative diagnostic method despite having lower sensitivity.&lt;/p&gt;

Resection and postoperative pazopanib for intraspinal recurrent solitary fibrous tumor: illustrative case.

Intracranial solitary fibrous tumors (SFTs) rarely recur in the spinal space. Only 4 cases of spinal recurrence from intracranial SFT have been reported; therefore, the optimal treatment of recurrent spinal SFT remains unclear. A 53-year-old woman with a history of resection of a right occipital anaplastic SFT presented with progressive back and side pain. She was diagnosed with an intradural extramedullary tumor ventral to the spinal cord at the T5-7 level. She underwent tumor resection with T5-6 laminectomy and T4 and T7 partial laminectomy. The tumor was completely removed in a piecemeal fashion using an ultrasonic aspirator with careful control of bleeding. Her symptoms quickly improved after the surgery, and she returned to normal life. The tumor was diagnosed as SFT. Pazopanib was administered postoperatively. Despite the recurrence of the intracranial tumor, the patient was alive without recurrence of the spinal tumor 14 months after resection. Although rare, intracranial SFTs have a risk of spinal recurrence. Complete resection of a recurrent spinal SFT can be achieved even in the ventral location. Pazopanib could be a possible therapeutic option for preventing local tumor recurrence in the management of recurrent spinal SFT. https://thejns.org/doi/10.3171/CASE24217.

Intracranial Solitary Fibrous Tumor with Concurrent Meningioma: Case Report and Review of the Literature

Abstract Introduction The present study describes a case of an intracranial solitary fibrous tumor (iSFT) concurrent with meningioma in different anatomical regions. Case Description A female patient, 64-years-old, presented with an 18-month history of progressive vision impairment in the right eye and no other neurological symptoms. The magnetic resonance imaging (MRI) revealed two solid and expansive lesions: one with right interhemispheric occipital location and dependent on the falx cerebri, and another located in the anterior skull base. We opted for a right frontotemporal craniotomy for the first tumor, and a right occipital craniotomy, 41-days later, for the second one, showing no postoperative complications. Histological and immunohistochemical findings confirmed the diagnosis of a grade-I fibrous meningioma and a grade-III SFT. After 9 months of follow-up, the patient showed vision improvement and no signs of neurological compromise or tumor recurrence in the last MRI. Conclusions The present study describes the first reported case of a patient with an intracranial SFT associated with a meningioma in different anatomical locations. The involved pathogenesis and evolution of both coexisting tumors are still unknown, which highlights the need for more case reports on them.

Evaluation of preoperative magnetic resonance imaging features and diagnostic effectiveness of grades II and III intracranial solitary fibroma

ObjectivesTo explore the value of preoperative magnetic resonance imaging (MRI) characterization of intracranial solitary fibrous tumors (ISFT) and to evaluate the effectiveness of preoperative MRI features in predicting pathological grading.Materials and methodsThis retrospective analysis comprised the clinical and preoperative MRI characterization of 55 patients with ISFT in our hospital, including 27 grade II cases and 28 grade III cases confirmed by postoperative pathology. Variables included age, sex, tumor location, cross-midline status, signal characteristics of T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), T2-fluid-attenuated inversion recovery (T2-FLAIR), and diffusion‑weighted imaging (DWI), peritumoral edema, intralesional hemorrhage, focal necrosis/cystic degeneration, tumor empty vessel, maximum tumor diameter, maximum, minimum, and average values of apparent diffusion coefficient (ADCmax, ADCmin, and ADCmean), tumors enhancement mode, meningeal tail sign, skull invasion, cerebral parenchymal invasion, and venous sinus involvement. The independent samples t test or Mann–Whitney U test was performed to compare continuous data between the two groups, and the Pearson chi-squared test or Fisher’s exact test was used to compare categorical data. In addition, bivariate logistic regression was performed to construct a comprehensive model, and receiver operating characteristic (ROC) curves were generated to calculate the areas under the curve (AUCs), thereby determining the value of each parameter in the differential diagnosis of grades II and III ISFT.ResultsThe mean age at onset was similar between patients with grades II and III ISFT (46.77 ± 14.66 years and 45.82 ± 12.07 years, respectively). The proportions of men among patients with grades II and III ISFT were slightly higher than those of female patients (male/female: 1.25 [15/12] and 1.33 [16/12], respectively). There were significant differences between grades II and III ISFT in the T2-FLAIR and DWI signal characteristics, maximum, minimum, and average values of the apparent diffusion coefficient (ADCmax, ADCmin, and ADCmean), tumor location, and skull invasion (P = 0.001, P = 0.018, P = 0.000, P = 0.000, P = 0.000, P = 0.010, and P = 0.032, respectively). However, no significant differences were noted between grades II and III ISFT in age, sex, cross-midline status, T1WI and T2WI signal characteristics, peritumoral edema, intralesional hemorrhage, focal necrosis/cystic degeneration, tumor empty vessel shadow, enhancement mode, meningeal tail sign, maximum tumor diameter, brain parenchyma invasion, or venous sinus involvement (all P > 0.05). Moreover, binary logistic regression analysis showed that the model accuracy was 89.1% when ADCmin was included in the regression equation. Moreover, ROC curve analysis showed that the AUC of ADCmin was 0.805 (0.688, 0.922), sensitivity was 74.1%, specificity was 75.0%, and the cutoff value was 672 mm2/s.ConclusionsGrade III ISFT patients displayed more mixed T2-FLAIR signal characteristics and DWI signal characteristics than grade II patients, as shown by higher skull invasion and tumor mass collapse midline distribution and lower ADCmax, ADCmean, and ADCmin values. The ADCmin value was significant in the preoperative assignment of grades II and III ISFT, thereby contributing to enhanced accuracy in the imaging grading diagnosis of the disease.

Intracranial solitary fibrous tumors: Clinical, radiological, and histopathological insights along with review of literature

BackgroundIntracranial solitary fibrous tumors (SFTs) are rare mesenchymal neoplasms, often challenging to diagnose due to their resemblance to meningiomas and other central nervous system tumors. While advancements in molecular genetics have aided in classification, diagnostic nuances and optimal management strategies remain areas of interest. Materials and methodsThis retrospective study analyzed 11 cases of intracranial SFTs treated at a neurosurgical centre in India between February 2020 and January 2024. Clinical data, radiological findings, histopathological features, and follow-up details were reviewed. Immunohistochemistry, particularly STAT6, facilitated diagnosis confirmation. ResultsThe median age of presentation was 32 years, with a male predominance. Headache was the most common presenting symptom, often leading to misdiagnosis as meningiomas on radiological imaging. Histologically, SFTs exhibited spindle to ovoid cells with staghorn vessels and collagenized stroma, posing challenges in differential diagnosis. WHO grading predominantly revealed grade 1 tumors, though recurrence occurred, emphasizing the importance of long-term follow-up. Immunohistochemistry, particularly STAT6, played a pivotal role in distinguishing SFTs from other entities. ConclusionIntracranial SFTs present diagnostic challenges due to overlapping features with other tumors, warranting a comprehensive approach integrating clinical, radiological, and histopathological findings. Immunohistochemistry, particularly STAT6, emerges as a valuable diagnostic tool. Long-term follow-up is essential for monitoring recurrence and potential malignant transformation. Further research is needed to delineate optimal treatment strategies, including the role of radiotherapy in SFT management.

A Radiomics Model for the Differentiation of Intracranial Solitary Fibrous Tumor/Hemangiopericytoma and Meningioma Based on Multiparametric Magnetic Resonance Imaging.

Although the imaging findings of intracranial solitary fibrous tumor (SFT)/hemangiopericytoma (HPC) and meningioma are similar, their treatment and prognosis are quite different. Accurate preoperative identification of these two types of tumors is crucial for individualized treatment. The aim of this study was to develop a radiomics model for the differentiation of intracranial SFT/HPC and meningioma based on multiparametric magnetic resonance imaging (mpMRI). A total of 99 patients from July 2012 to July 2018 with histologically and immunohistochemically confirmed SFT/HPC (n = 40) or meningiomas (n = 59) were retrospectively analyzed. A total of 1118 features were extracted based on its image shape, intensity and texture features. The logistic regression (LR) and multi-layer artificial neural network (ANN) classifiers were used to classify SFT/HPC and meningioma. The predictive performance was calculated using receiver operating characteristic curves (ROC). We found significant difference in terms of sex between the SFT/HPC and meningioma group (χ2= 4.829, P < 0.05), but no significant difference was found in age (P > 0.05). The most significant radiomics features included five shape and four first-order level features. For the LR classifier, the prediction accuracy of SFT/HPC was 71.0% and meningioma was 78.7%. For the ANN classifier, the prediction accuracy of SFT/HPC was 83.9% and meningioma was 80.9%. Both of the two classifiers achieved a high accuracy rate, but ANN was better. Radiomics features, especially when combined with an ANN classifier, can provide satisfactory performance in distinguishing SFT/HPC and meningioma.

Intracranial solitary fibrous tumor in a 15-year-old girl: illustrative case.

Solitary fibrous tumor (SFT) is an infrequent spindle cell tumor derived from mesenchymal tissue, which can manifest in diverse anatomical locations, primarily in the pleural cavity and infrequently in the central nervous system. SFT is predominantly observed in individuals aged between 40 and 50 years old, with a slightly higher occurrence in males than in females. This case report describes a female, age 15, who had migraines for 2 months prior to the diagnosis of an intracranial tumor. Computed tomography and magnetic resonance imaging showed a mass located in the right parietooccipital region with surrounding edema and a compressed right lateral ventricle. Neurosurgery was utilized to successfully remove the mass, and single intracranial fibrous tumor (grade I) was identified by postoperative pathological analysis. During an 8-month follow-up period, the patient did not experience any recurrences. SFT is often misdiagnosed as meningioma because of their similar imaging characteristics. However, identifying the distinctive features of SFT on magnetic resonance imaging can distinguish it from meningioma and help to select appropriate treatment. The complete preoperative imaging data for this case indicated a highly vascularized tumor. Preoperative vascular embolization treatment reduced any difficulties during the subsequent tumor resection and minimized intraoperative bleeding.

Development of an MRI-Based Comprehensive Model Fusing Clinical, Radiomics and Deep Learning Models for Preoperative Histological Stratification in Intracranial Solitary Fibrous Tumor.

Accurate preoperative histological stratification (HS) of intracranial solitary fibrous tumors (ISFTs) can help predict patient outcomes and develop personalized treatment plans. However, the role of a comprehensive model based on clinical, radiomics and deep learning (CRDL) features in preoperative HS of ISFT remains unclear. To investigate the feasibility of a CRDL model based on magnetic resonance imaging (MRI) in preoperative HS in ISFT. Retrospective. Three hundred and ninety-eight patients from Beijing Tiantan Hospital, Capital Medical University (primary training cohort) and 49 patients from Lanzhou University Second Hospital (external validation cohort) with ISFT based on histopathological findings (237 World Health Organization [WHO] tumor grade 1 or 2, and 210 WHO tumor grade 3). 3.0 T/T1-weighted imaging (T1) by using spin echo sequence, T2-weighted imaging (T2) by using fast spin echo sequence, and T1-weighted contrast-enhanced imaging (T1C) by using two-dimensional fast spin echo sequence. Area under the receiver operating characteristic curve (AUC) was used to assess the performance of the CRDL model and a clinical model (CM) in preoperative HS in the external validation cohort. The decision curve analysis (DCA) was used to evaluate the clinical net benefit provided by the CRDL model. Cohen's kappa, intra-/inter-class correlation coefficients (ICCs), Chi-square test, Fisher's exact test, Student's t-test, AUC, DCA, calibration curves, DeLong test. A P value <0.05 was considered statistically significant. The CRDL model had significantly better discrimination ability than the CM (AUC [95% confidence interval, CI]: 0.895 [0.807-0.912] vs. 0.810 [0.745-0.874], respectively) in the external validation cohort. The CRDL model can provide a clinical net benefit for preoperative HS at a threshold probability >20%. The proposed CRDL model holds promise for preoperative HS in ISFT, which is important for predicting patient outcomes and developing personalized treatment plans. 3 TECHNICAL EFFICACY: Stage 2.

Developing a Nomogram to Stratify Intracranial Solitary Fibrous Tumor Recurrence

To develop a nomogram to stratify tumor recurrence (TR) in intracranial solitary fibrous tumors (ISFTs) based on the clinical, radiological, and pathological features. A total of 215 patients from Beijing Tiantan Hospital, Capital Medical University and 48 patients from Lanzhou University Second Hospital, diagnosed with ISFT based on histopathological findings, were included. The patients were randomly divided into training and test cohorts at a ratio of 8:2. Information regarding clinical, radiological, and histopathological features, and the clinical outcomes was retrospectively analyzed. Univariate and multivariate analyses were performed using the Cox proportional hazard model for TR in the training cohort. A nomogram incorporating the independent risk factors was developed in the training cohort and validated in the test cohort. Its predictive performance was analyzed using the Harrell C-index. Decision curve analysis (DCA) was used to evaluate the net clinical benefit. The Harrell C-indices for TR at 3 and 5 years were 0.845 (0.578-0.944) and 0.807 (0.612-0.901) for the test cohort, respectively. In the test cohort, the nomogram provided a net clinical benefit in the DCA over the TR scheme or non-TR scheme. Although postoperative radiotherapy (PORT) was useful for TR prevention, high doses (≥46Gy) were not superior to lower doses in prolonging the progression-free survival. The nomogram obtained in our study had a good predictive performance and could be used for ISFT patients.

Intracranial Solitary Fibrous Tumor Mimicking Meningioma.

Solitary fibrous tumor (SFT) is a clinically rare tumor derived from mesenchymal spindle cells. Central nervous system SFT represents only 0.09% of tumors occurring on the meninges, while intracranial solitary fibrous tumors (ISFT) are even more rare. Due to the similar genetic characteristics it shares with hemangiopericytoma, in 2016, the World Health Organization (WHO) classified it as a single disease called solitary fibrous tumor (SFT)/hemangiopericytoma. We reported a case of a 60-year-old female with an intracranial solitary fibrous tumor (ISFT). The patient's magnetic resonance imaging showed a mass adhering extensively to the dura mater, with adjacent thickening of the meninges and evidence of a meningeal tail sign. These radiologic findings suggested a meningioma. The tumor was surgically removed and sent for pathologic examination, which confirmed that the tumor was consistent with a solitary fibrous tumor(WHO III). Due to its rarity and similarities with meningioma, ISFT is often misdiagnosed as other types of brain tumors. ISFT is poorly understood and poses a diagnostic challenge. Our case report presents several features suggestive of meningioma, but histopathological examination after surgery confirmed the diagnosis of SFT. Knowledge of these tumors is crucial for neurosurgeons to include them in preoperative differential diagnosis.

Intracranial Solitary Fibrous Tumour: Case Report

Intracranial solitary fibrous tumor is a rare mesenchymal tumour. The diagnosis is based on the histological study given the clinical and radiological character that can simulate other benign or malignant pathologies especially meningioma. We report the case of a patient with an intracranial solitary fibrous tumor. We aim to discuss the clinical, radiological, histological and immunohistochemical features of Intracranial solitary fibrous tumor as well as the new grading system reported in the fifth edition of the WHO classification of central nervous system tumours.

Utility of Apparent Diffusion Coefficient Histogram Analysis in Differentiating Microcystic Meningioma from Intracranial Solitary Fibrous Tumor

To investigate the possibility of histogram analysis of apparent diffusion coefficient (ADC) maps in differentiating microcystic meningioma (MM) from intracranial solitary fibrous tumor (SFT). Eighteen patients with MM and 23 patients with SFT were enrolled in this retrospective study. Conventional magnetic resonance imaging (MRI) features and 9 ADC histogram parameters (including mean, first (ADC1), 10th (ADC10), 50th (ADC50), 90th (ADC90), and 99th (ADC99) percentiles ADC, as well as variance, skewness, and kurtosis) between MM and SFT were compared. The diagnostic performance of the optimal parameter was determined by the receiver operating characteristic analysis. SFT showed a significantly lower mean, ADC1, ADC10, ADC50, ADC90, and ADC99 than MM (all P<0.05), while no significant difference was found in conventional MRI features or other ADC histogram parameters (all P>0.05). ADC1 was identified as the optimal parameter in differentiating between MM and SFT, which achieved an area under the curve of 0.861, with sensitivity, specificity, and accuracy of 78.26%, 88.89%, and 82.93%, respectively. MM and SFT show overlapping conventional MRI features. ADC histogram analysis helps to differentiate between MM and SFT, with ADC1 being the optimal parameter with the best discrimination performance.

Impact of extent of resection and postoperative radiotherapy on survival outcomes in intracranial solitary fibrous tumors: a systematic review and meta-analysis.

The knowledge of optimal treatments for patients with intracranial solitary fibrous tumor (SFT) is limited, with inconclusive results from previous studies. In this study, we conducted a meta-analysis of relevant studies to identify the prognostic impact of the extent of resection (EOR) and postoperative radiotherapy (PORT) on survival outcomes of patients with intracranial SFT. We searched the Medline, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) to identify relevant studies published till April 2022. Progression-free survival (PFS) and overall survival (OS) were the outcomes of interest. Differences between two cohorts (gross total resection [GTR] vs. subtotal resection [STR] and PORT vs. surgery only) were estimated by calculating hazard ratios. Twenty-seven studies were selected for the meta-analysis, including data of 1348 patients (GTR, n = 819 vs. STR, n = 381 and PORT, n = 723 vs. surgery only, n = 578). Pooled hazard ratios of PFS (1, 3, 5, and 10years) and OS (3, 5, and 10years) revealed that the GTR cohort showed sustained superiority over the STR cohort. In addition, the PORT cohort was superior to the surgery-only cohort with respect to all PFS periods. Although the 10-year OS between the two cohorts was not statistically different, PORT showed significantly better 3- and 5-year OS than surgery only. The study findings suggest that GTR and PORT provide significant benefits for PFS and OS. Aggressive surgical resection of tumors to achieve GTR followed by PORT should be implemented as optimal treatments for all patients with intracranial SFT when feasible.

Methylation classifier array and classification of solitary fibrous tumors.

e23522 Background: Solitary fibrous tumors (SFTs) are fibroblastic tumors which carry a characteristic NAB2::STAT6 gene rearrangement. SFTs represent a heterogenous group that may arise in multiple locations and have variable risk of progression. Despite a consistent oncogenic driver, there is little biological data explaining this variability. Recently, the German Cancer Research Network (DKFZ) have modified their brain tumor methylation classifier for use in sarcomas. We subjected solitary fibrous tumors diagnosed at our institution to a validated, in-house sarcoma methylation array classifier modeled after that of the DKFZ in order to assess for differences in methylation patterns that may account for biological or clinical variances. Methods: Twenty-eight primary site SFTs from 2011-2021 were subjected to the sarcoma methylation classifier. Histologic diagnosis was confirmed by STAT6 immunohistochemistry or by the presence of the NAB2::STAT6 fusion. The methylation classifier was run on the Illumina iScan platform and the resulting IDAT files were analyzed via a custom bioinformatics pipeline. The sarcoma classifier was trained using the same samples and normalization strategies used by the DKFZ group and validated using the same publicly available samples. Results: Methylation data for each tumor was collected, given a classification score, and visualized by t-distributed stochastic neighbor embedding (t-SNE). We noted three distinct groups of SFTs on the t-SNE plot. Group 1 was comprised of all eight intracranial SFTs and were correctly classified as SFT (classifier score ≥0.9). Group 2 contained nine pleural-based tumors and one SFT each from the mediastinum and bladder wall. Classification was successful in only seven of eleven tumors. Group 3 SFTs predominantly arose in the soft tissues or bone (two pelvis, four extremity, and one mediastinum) and all failed accurate classification. Finally, two orbital SFTs stratified separately from all groups on t-SNE plot but did achieve an appropriate classification. There were no significant differences in grade or risk stratification among the three groups. Conclusions: Our preliminary data show differential clustering based on tumor location, suggesting biological differences between intracranial, pleural/visceral, and connective tissue locations. These results highlight the heterogeneity of these tumors and the inadequacy of the current methylation classification scheme for SFT. Future directions will include analysis of additional cases, gene expression patterns, and outcome data.

The value of whole-volume apparent diffusion coefficient histogram analysis in preoperatively distinguishing intracranial solitary fibrous tumor and transitional meningioma.

To investigate the value of whole-volume apparent diffusion coefficient (ADC) histogram analysis in preoperatively distinguishing intracranial solitary fibrous tumors (SFT) from transitional meningiomas (TM), thereby assisting the establishment of the treatment protocol. Preoperative diffusion-weighted imaging datasets of 24 patients with SFT and 28 patients with TM were used to extract whole-volume ADC histogram parameters, including variance, skewness, kurtosis, and mean, as well as 1st (AP1), 10th (AP10), 50th (AP50), 90th (AP90), and 99th (AP99) percentiles of ADC using MaZda software. The independent t-test or Mann-Whitney U test was used to compare the differences between ADC histogram parameters of SFT and TM. Receiver operating characteristic (ROC) curves were generated to evaluate the performance of significant ADC histogram parameters. Spearman's correlation coefficients were calculated to evaluate correlations between these parameters and the Ki-67 expression levels. SFT exhibited significantly higher variance, and lower AP1 and AP10 (all P < 0.05) than TM. The best diagnostic performance was obtained by variance, with an area under the ROC curve of 0.848 (0.722-0.933). However, there was no significant difference in skewness, kurtosis, mean, or other percentiles of ADC between the two groups (all P > 0.05). Significant correlations were also observed between the Ki-67 proliferation index and variance (r = 0.519), AP1 (r = -0.425), and AP10 (r = -0.372) (all P < 0.05). Whole-volume ADC histogram analysis is a feasible tool for non-invasive preoperative discrimination between intracranial SFT and TM, with variance being the most promising prospective parameter.

The adverse effect of anticancer drug toremifene on vascular smooth muscle cells is an important aspect of its tumor growth inhibition.

Toremifene (TOR) is widely used as an antineoplastic drug and has an inhibitory effect on angiogenesis in mesenteric desmoid tumors and vascular intracranial solitary fibrous tumors. However, no study has investigated the direct effect of TOR on vascular cells. This study aimed at exploring the effect of TOR on the behaviors of vascular smooth muscle cells (VSMCs). Human aortic umbilical vascular smooth muscle cells (HAVSMCs) were treated by TOR. Cell morphology, migration, adhesion, and proliferation assay were investigated. The cell cycle, apoptosis, mitochondrial membrane potential, and reactive oxygen species were assessed using flow cytometry. Caspase-3 and 9 activities were assayed using Caspase-3 and Caspase-9 Activity Assay kits, respectively. Immunofluorescence and Western blot assays were carried out to characterize protein expressions of PCNA, p53, and Rho/ROCK signaling pathway. TOR damaged cytoskeleton, inhibited VSMC proliferation, migration, and adhesion, and induced abnormal cell morphology and apoptosis. The antiproliferative activity of TOR was associated with the induction of G0/G1 phase arrest, blocking the cell cycle. TOR disrupted intracellular reactive oxygen species and mitochondrial membrane potential, and enhanced p53 expression and the activities of caspase-3 and caspase-9. Thus, TOR-induced apoptosis by the mitochondrial signaling pathway. Additionally, TOR induced decreased Rho, ROCK, MLC, and pMLC proteins. Collectively, TOR may affect multiple behaviors of VSMCs by damaging cytoskeleton through the Rho/ROCK pathway. The adverse effect of TOR on VSMCs could be considered as an important aspect of tumor growth inhibition.

Intracranial solitary fibrous tumor with delayed symptomatic metastasis to the lumbar spine: illustrative case.

Intracranial solitary fibrous tumors (SFTs), formerly known as hemangiopericytomas, are rare, aggressive mesenchymal extra-axial tumors typically treated via resection, often with preoperative embolization and postoperative radiation and/or antiangiogenic therapy. Although surgery confers a significant survival benefit, local recurrence and distant metastasis are not uncommon and may occur in a delayed fashion. The authors describe the case of a 29-year-old male who initially presented with headache, visual disturbance, and ataxia, and was found to have a large right tentorial lesion with mass effect on surrounding structures. He underwent tumor embolization and resection with gross total resection achieved and pathology consistent with World Health Organization grade 2 hemangiopericytoma. The patient recovered well, but 6 years later presented with low back pain and lower extremity radiculopathy and was found to have metastatic disease within the L4 vertebral body causing moderate central canal stenosis. This was successfully treated with tumor embolization followed by spinal decompression and posterolateral instrumented fusion. Metastasis of intracranial SFT to vertebral bone is exceedingly rare. To our knowledge this is only the 16th reported case. Serial surveillance for metastatic disease is imperative in patients with intracranial SFTs given their propensity and unpredictable time course for distant spread.

Intracranial Solitary Fibrous Tumour Management: A French Multicentre Retrospective Study.

Intracranial solitary fibrous tumour (iSFT) is an exceptional mesenchymal tumour with high recurrence rates. We aimed to analyse the clinical outcomes of newly diagnosed and recurrent iSFTs. We carried out a French retrospective multicentre (n = 16) study of histologically proven iSFT cases. Univariate and multivariate Cox models were used to estimate the prognosis value of the age, location, size, WHO grade, and surgical extent on overall survival (OS), progression-free survival (PFS), and local recurrence-free survival (LRFS). Eighty-eight patients were included with a median age of 54.5 years. New iSFT cases were treated with gross tumour resection (GTR) (n = 75) or subtotal resection (STR) (n = 9) and postoperative radiotherapy (PORT) (n = 32, 57%). The median follow-up time was 7 years. The median OS, PFS, and LRFS were 13 years, 7 years, and 7 years, respectively. Forty-two patients experienced recurrence. Extracranial metastasis occurred in 16 patients. Median OS and PFS after the first recurrence were 6 years and 15.4 months, respectively. A higher histological grade was a prognosis factor for PFS (p = 0.04) and LRFS (p = 0.03). GTR influenced LRFS (p = 0.03). GTR provided benefits as a first treatment for iSFTs. However, approximately 40% of patients experienced relapse, which remains a challenging state.