The Feasibility And Value Of Studying WHO Classification,Cell Subtypes And Peritumoral Edema In Meningioma Based On Quantitative Dynamic Contrast-Enhanced Magnetic Resonance Imaging

Part 1Quantitative Study of WHO Classification in Meningioma based on Dynamic Contrast-Enhanced Magnetic Resonance ImagingBackgroundMeningiomas are extra-brain tumors with abundant blood supply and many new blood vessels.Generally,there is no blood-brain barrier.The passage of contrast agent is not blocked.Some scholars use magnetic resonance perfusion imaging parameter MTT to distinguish intracerebral and extracerebral tumors according to their characteristics.The effects are compared.it is good.In addition,meningioma has excessive blood vessel proliferation,distorted blood vessel shape and sinusoidal changes,and its permeability is also high.Dynamic contrast-enhanced MRI（Dynamic contrast-enhanced MRI,DCE-MRI）is a relatively new MRI technology,and dynamic contrast-enhanced MRI（Dynamic contrast-enhanced MRI,DCE-MRI）is a relatively new Magnetic resonance imaging technology belongs to the category of MRI perfusion imaging,which can quantitatively reflect the microcirculation perfusion of tissues.At present,the quantitative analysis of DCE-MRI permeability parameters has been widely used in fields such as the differentiation of benign and malignant breast and lung tumors,the classification of gliomas,and the correlation between bone marrow microvascular permeability and trabecular bone changes.At present,domestic and foreign studies have also found that the application of DCE technology has higher K^trans（volume transfer constant）values and V_e（extravascular extracellular space volume ratio）values of malignant tumors.However,research goals at home and abroad are basically focused on glioma,and there are few studies on meningiomas.This topic applies DCE-MR imaging technology to meningioma.Meningioma can be divided into grades I,II,and III according to the WHO（The World Health Organization）classification.According to the WHO classification,meningiomas can be classified into grades I,II,and III,and grade I meningiomas are benign tumors.Routine MRI can clearly locate and qualitatively diagnose it.Grade II and III meningiomas are anaplastic or malignant meningiomas,which often invade brain tissue and adjacent bone and scalpand are accompanied by peritumoral edema.They are often confused with malignant tumors such as hemangiopericytoma and glioma.Routine MRI examinations have certain difficulties in the qualitative diagnosis of grade II and III meningioma.Therefore,it is more important to study the tumor heterogeneity of meningiomas at all levels of WHO,which will provide reference for clinical preoperative evaluation and the formulation of postoperative radiotherapy and chemotherapy.The first part of the study interprets the differences between the WHO grades of meningiomas from the perspective of microvascular permeability and provides a certain auxiliary role for imaging diagnosis.ObjectiveThe DCE-MR imaging technique was used to analyze the differences in microvascular permeability among the WHO grades of meningioma,the diagnostic efficacy of the parameters,and the analysis of related factors.MethodsA retrospective analysis of all meningioma patients undergoing surgery.All patients underwent DCE-MRI scan.The quantitative parameters of DCE-MRI include volume transfer constant(K^trans),rate constant(K_ep),extracellular volume（V_e）and mean plasma volume（V_p）,which are obtained using the extended Tofts-Kety two-chamber model.Measurement data were tested for normality by independent sample t test,and independent sample t test was used for comparison between groups;indicators with non-normal distribution were represented by median and interquartile range（IQR）,and comparison between groups was used Mann-Whitney U test.Count data is expressed as a percentage（%）,and comparisons between groups are performed by chi-square test or Fisher’s exact probability method.Univariate and multivariate logistic regression analysis were used to evaluate the correlation between dependent variables such as age and gender and the WHO classification.The receiver operating characteristic curve（ROC curve）was used to evaluate the diagnostic efficacy of WHO classification.Results1.Patients of 184 cases who were pathologically diagnosed as meningioma were included in this study.There were 53 males and 131 females,aged from 32 to 88 years old.There were 145 cases of WHO grade I meningioma,and 39 cases of WHO grade II and III meningioma.K^transand K_epin the tumor and K^transand K_eparound the tumor in the WHO II and III meningioma group were higher than those in the WHO I meningioma group,the difference was statistically significant（P<0.001）;while V_eand V_pin the tumor between the two groups There was no statistical difference in V_eand V_paround the tumor.2.There was a statistically significant difference in the degree of peritumoral edema between the WHO grade I meningioma group and the WHO grade II and III meningioma groups（p<0.001）.3.There was a statistically significant difference in tumor volume between the two groups（P<0.001）.4.Univariate regression analysis showed that K^trans（tumor body）,K_ep（tumor body）,K^trans（peritumoral brain area）,K_ep（peritumoral brain area）,tumor size is related to the WHO grade of meningioma.Multivariate regression analysis showed that K^trans（tumor body）,K_ep（tumor body）,K^trans（peritumoral brain area）,and K_ep（peritumoral brain area）were independently related to meningiomas.5.ROC analysis shows that K^trans（tumor body）,K_ep（tumor body）,K^trans（peritumoral brain area）,and K_ep（peritumoral brain area）have higher diagnostic efficiency,with AUC values of 0.839（95%CI:0.770-0.908）,respectively,0.824（95%CI:0.742-0.905）,0.812（95%CI:0.739-0.886）,0.781（95%CI:0.694-0.868）;when K^trans（tumor body）=0.162,identify WHO grade I meningioma The sensitivity of WHO II and III meningioma is 0.923,and the specificity is 0.593;when K_ep（tumor body）=0.641,the sensitivity of distinguishing WHO II and III meningioma from WHO II and III meningioma is 0.872,which is specific The sensitivity is 0.607;when K^trans（peritumoral brain area）=0.001,the sensitivity for distinguishing WHO grade I meningioma from WHO II and III meningioma is 0.667,and the specificity is 0.703;when K_ep（peritumoral brain area）=0.308,The sensitivity for distinguishing WHO grade I meningioma from WHO grade II and III meningioma is 0.641 and specificity is 0.697;K^trans（tumor body）combined with K_ep（tumor body）,K^trans（peritumoral area）combined with K_ep（peritumoral brain area）)Also has high diagnostic efficiency,with AUC values of0.912（95%CI:0.859-0.966）and 0.869（95%CI:0.800-0.939）respectively;K^trans（tumor body）combined with K_ep（tumor body）distinguishes the two groups The sensitivity and specificity were 0.769 and 0.834,respectively;the sensitivity and specificity of K^trans（peritumoral brain area）combined with K_ep（peritumoral brain area）to distinguish the two groups were 0.821 and 0.717,respectively.ConclusionsThe microvascular permeability parameters of K^transand K_epin meningioma tumors and K^transand K_epin peritumoral brain area are of great significance for evaluating the WHO classification of meningioma and have good diagnostic value.Part 2The feasibility Study of Dynamic Contrast-Enhanced Magnetic Resonance Imaging on the Difference of Microvascular Permeability between Pathological Cell Subtypes of MeningiomasBackgroundAccording to the WHO classification,meningiomas can be divided into grades I,II,and III.Grade I meningiomas are benign tumors.Routine MRI can clearly locate and qualitatively diagnose meningiomas.Grade II and III meningiomas are anaplastic or malignant meningiomas,which often invade brain tissue and adjacent bone and scalp.Using conventional enhanced MR or CT examination,combined with whether the tumor has brain tissue and adjacent skull invasion,the differential diagnosis of WHO grade I meningioma is relatively easy.However,there are many cell subtypes in WHO grade I meningioma,but they all have similar biological characteristics as WHO grade I meningioma.Routine MR or CT enhancement examination cannot diagnose the cell subtype classification of WHO grade I meningioma.It needs to be further classified and diagnosed by pathology.Among meningiomas,WHO grade I meningiomas account for about 90%,accounting for a relatively large proportion,while WHO grade I meningiomas have a higher incidence of mesothelial cell type and transitional type,fibrous type,hemangioma type,sand grain type,and microcystic type.（1.6%）,lymphocyte-rich type（1.7%）,secretory type（1.6%）and metaplasia type are all relatively low.In the first part of the study,DCE-MR imaging technology has been used to differentially diagnose meningiomas in the WHO classification.Whether this technology can also differentially diagnose meningiomas with different pathological cell subtypes at the same level requires further research.This study aims to use DCE-MR imaging technology to break the conventional MR technology,from the perspective of tumor microvascular permeability,to study the difference between transitional meningioma and dermal cell meningiomas in WHO grade I meningioma,and to interpret the two similarities from a new perspective The difference in the biological characteristics of meningiomas is an extension of conventional imaging techniques and provides help for the diagnosis of cell subtypes of meningiomas.ObjectiveThe purpose of this study is to use DCE-MR imaging technology to analyze the difference in microvascular permeability and the diagnostic efficacy of the parameters between transitional meningioma and dermal cell meningioma.MethodsA retrospective analysis of all patients undergoing surgery with transitional meningioma and dermal cell meningioma was performed.All patients underwent DCE-MRI scan.The quantitative parameters of DCE-MRI include volume transfer constant（Ktrans）,rate constant（Kep）,extracellular volume（Ve）and mean plasma volume（Vp）,which are obtained using the extended Tofts-Kety two-chamber model.Measurement data were tested for normality by independent sample t test,and independent sample t test was used for comparison between groups;indicators with non-normal distribution were represented by median and interquartile range（IQR）,and comparison between groups was used Mann-Whitney U test.Count data is expressed as a percentage（%）,and comparisons between groups are performed by chi-square test or Fisher’s exact probability method.The receiver operating characteristic curve（ROC curve）was used to evaluate the diagnostic efficiency of postoperative pathology classification.Results（1）63 cases of transitional meningiomas and 56 cases of dermal cell meningiomas were included in this part of the study.There were 32 males and 87 females.Among them,there were 16 males and 47 females of transitional meningioma;16 males and40 females of epithelial meningioma.The average age of transitional meningiomas is58 years,and the average age of skin cell meningiomas is 60 years.（2）There was a statistically significant difference in Vp parameters between transitional meningiomas and dermal cell meningioma tumors（p<0.001）,and there was no statistical difference in other parameters.（3）ROC analysis shows that Vp（tumor body）has a certain diagnostic power for differentiating transitional meningioma and dermal cell meningioma,with an AUC value of 0.732（95%CI: 0.642-0.822）,when Vp（tumor body）= 0.074.The sensitivity for differentiating transitional meningioma and dermal cell meningioma was 0.750,and the specificity was 0.667.ConclusionsThe value of Vp parameter in the tumor has a certain diagnostic power for differentiating transitional meningioma and dermal cell meningioma.Part 3Analysis of Related Factors of Peritumoral Brain Edema in Transitional Meningioma by Dynamic Contrast-Enhanced Magnetic Resonance ImagingBackgroundDynamic contrast-enhanced MRI（DCE-MRI）is a relatively new magnetic resonance imaging technology,which belongs to the category of MRI perfusion imaging,which can quantitatively reflect the microcirculation perfusion of tissues.At present,the quantitative analysis of DCE-MRI microvascular permeability parameters has been widely used in the differentiation of benign and malignant breast and lung tumors,the classification of gliomas,and the correlation between bone marrow microvascular permeability and trabecular bone changes.Meningiomas are mostly benign,having a capsule formed by connective tissue,sometimes with calcification and ossification.A small number of meningiomas have cystic degeneration and necrosis of the blood-brain barrier.Meningiomas can be divided into grades I,II,and III according to the WHO classification.The incidence of WHO grade I meningiomas is the highest.As the WHO grade increases,the degree of malignancy of meningiomas also increases.Although meningiomas are mainly located outside the intracranial axis and have slow progressing and usually benign histological features,they are usually associated with peritumoral edema.About 50% of meningiomas have peritumoral brain edema.Clinically,the perioperative mortality and morbidity of meningioma surgery may be related to the peritumor brain edema（PTBE）of meningioma.Cerebral edema can cause severe neurological deficits and limit the visual field during surgical approach.Although tumor size,tumor location,histological type,tumor blood supply,tumor VEGF levels and sex hormone levels have been reported to be associated with peritumoral edema,the mechanism of meningioma producing peritumoral edema has not been fully elucidated.In recent years,there have been many studies on the type of arterial blood supply and vascular endothelial growth factors（VEGFs）among the mechanism factors of PTBE.The arterial supply of meningiomas usually comes from the dural branch of the external carotid artery.In some cases,dual blood supply can also form cortical blood vessels.The blood vessels in the dura mater are porous and not tightly connected;the histological characteristics of these dural blood vessels are related to the study of vascular permeability.VEGF promotes the formation of new blood vessels in tumors.The correlation between VEGF and the microvascular permeability parameter Ktransin gliomas has been confirmed by studies,and whether this correlation exists in meningioma is still controversial.It is well known that the peritumoral brain edema of WHO II and III meningioma is related to the surrounding infiltration of the tumor.Previous studies have shown that the peritumoral edema of WHO I may be mainly related to factors such as location,tumor size,and endocrine function.The possible causes of peritumoral brain edema of type meningioma are different.Therefore,this study collected 63 cases of WHO grade I transitional meningioma and used DCE-MRI to evaluate the microvascular permeability of transitional meningioma and the possible main mechanism of peritumoral edema.ObjectiveDCE-MRI was used to analyze the microvascular permeability of meningiomas and brain tissues around the tumor,and to compare the microvascular permeability of the peritumoral brain edema area and the non-peritumoral brain edema area.MethodsA retrospective analysis was performed on patients with WHO grade I transitional meningioma undergoing surgery.All patients underwent DCE-MRI scan,and the patients were divided into PTBE group and non-PTBE group according to whether there was brain edema around the tumor.The quantitative parameters of DCE-MRI include volume transfer constant（Ktrans）,rate constant（Kep）,extracellular volume（Ve）and mean plasma volume（Vp）,which are obtained using the extended Tofts-Kety two-chamber model.Logistic regression analysis method was used to explore the risk factors of PTBE.ResultsSeventy-two patients diagnosed with transitional meningioma were included in this study.There were 20 males and 52 females,aged from 32 to 88 years old.The Kep and Vp of patients with PTBE were significantly lower than those of patients without PTBE（Kep: 0.1852±0.0369 vs.0.5087±0.1590,P=0.010;Vp: 0.0090±0.0020 vs.0.0521±0.0262,P=0.007）,while Ktransand Vewere not significant Statistical difference（all P>0.05）.Multivariate regression analysis showed that the tumor size ≥10 cm3（OR=4.457,95%CI: 1.322 15.031,P=0.016）and Vp（OR=0.572,95%CI: 0.333 0.981,P=0.044）are independently related to the peritumoral brain edema of transitional meningioma.ConclusionsTumor size ≥ 10 cm3 and Vp are independently related to the PTBE of WHO grade I transitional meningioma,suggesting that tumor compression and cortical artery stealing may be the main causes of peritumoral brain edema.