Ki67 Proliferative Index and Peritumoral Brain Edema in Meningiomas: Do They Correlate? A Clinical Study on 56 Patients

Introduction: Meningiomas are the most common type of extra-axial neoplasm. Peritumoral brain edema (PTBE) can be seen around meningiomas while it may be absent in others. Despite that Ki67 proliferative index has been previously correlated with meningioma grades, no definite relationship has been established in relation to PTBE in meningioma patients. Objective: Correlate the peritumoral brain edema with the Ki67 proliferative index of meningiomas. Patients & Methods: Aclinical prospective study was conducted on 56 patients (47 women, 9 men;mean age 50.89 ± 12.55 years) diagnosed with meningiomas. All patients were evaluated regarding the presence of brain edema surrounding the lesion in pre-operative neuroimaging using T2W and FLAIR MR images. Immunohistochemical staining of Ki67 index (representing proliferative activity) was done. Correlation between presence of PTBE and Ki67 index values was evaluated. Results: PTBE was found in nearly half of the patients (48.2%), while the remaining (51.8%) of patients did not exhibit PTBE in their pre-operative neuroimaging. The mean value of Ki67 index in meningioma patients with PTBE was 4.83% compared to a value of 1.83% in patients without PTBE, P value = 0.014. Conclusion: High Ki67 indices are evident in meningiomas with surrounding peritumoral brain edema (PTBE).

THE RELATIONSHIP BETWEEN PERITUMORAL BRAIN EDEMA AND VASCULAR ENDOTHELIAL GROWTH FACTOR EXPRESSION IN PATIENTS WITH MENINGIOMA

Objective: To determine whether VEGF plays a role in the development of peritumoral brain edema. Methods 50 meningioma patients and their VEGF expression were studied. We took a monoclonal antibody from mouse to VEGF to stain the tumor cells, the vascular endothelial cells and the interstitial cells. The severity of brain edema was evaluated according to CT or MR scans by the following equation: edema index= V tumor +edema /Vtumor. The relationship between VEGF expression and edema index was analyzed statistically. Results VEGF was expressed in meningioma tumor cells, which is usually concentrated at the peripheral sites of the tumor. There was a positive linear correlation between the expression and the brain edema index. Conclusion VEGF may play a role in the development of peritumoral brain edema in meningioma patient.

Preoperatively predicting vessels encapsulating tumor clusters in hepatocellular carcinoma:Machine learning model based on contrast-enhanced computed tomography

BACKGROUND Recently,vessels encapsulating tumor clusters(VETC)was considered as a distinct pattern of tumor vascularization which can primarily facilitate the entry of the whole tumor cluster into the bloodstream in an invasion independent manner,and was regarded as an independent risk factor for poor prognosis in hepatocellular carcinoma(HCC).AIM To develop and validate a preoperative nomogram using contrast-enhanced computed tomography(CECT)to predict the presence of VETC+in HCC.METHODS We retrospectively evaluated 190 patients with pathologically confirmed HCC who underwent CECT scanning and immunochemical staining for cluster of differentiation 34 at two medical centers.Radiomics analysis was conducted on intratumoral and peritumoral regions in the portal vein phase.Radiomics features,essential for identifying VETC+HCC,were extracted and utilized to develop a radiomics model using machine learning algorithms in the training set.The model’s performance was validated on two separate test sets.Receiver operating characteristic(ROC)analysis was employed to compare the identified performance of three models in predicting the VETC status of HCC on both training and test sets.The most predictive model was then used to constructed a radiomics nomogram that integrated the independent clinical-radiological features.ROC and decision curve analysis were used to assess the performance characteristics of the clinical-radiological features,the radiomics features and the radiomics nomogram.RESULTS The study included 190 individuals from two independent centers,with the majority being male(81%)and a median age of 57 years(interquartile range:51-66).The area under the curve(AUC)for the combined radiomics features selected from the intratumoral and peritumoral areas were 0.825,0.788,and 0.680 in the training set and the two test sets.A total of 13 features were selected to construct the Rad-score.The nomogram,combining clinicalradiological and combined radiomics features could accurately predict VETC+in all three sets,with AUC values of 0.859,0.848 and 0.757.Decision curve analysis revealed that the radiomics nomogram was more clinically useful than both the clinical-radiological feature and the combined radiomics models.CONCLUSION This study demonstrates the potential utility of a CECT-based radiomics nomogram,incorporating clinicalradiological features and combined radiomics features,in the identification of VETC+HCC.

Brain Urea as a Potential Biomarker of Neoplasm Progression

Metabolic reprogramming is a key feature driving oncogenesis in cancers. Recent studies have revealed that protein metabolism is largely altered in gliomas facilitating its malignant growth. Urea is the end product of nitrogen metabolism which is mainly produced by arginase. The interdependence of arginase and other biochemical mechanisms triggered scientific research interest. This research aimed to investigate the relationships between the urea as the main parameter of protein metabolism and glioma progression. It was also the most pronounced relationship between urea and the level of the nuclear protein Ki-67 as a marker of proliferative activity and O-6-methylguanine-DNA methyltransferase (MGMT), which performs DNA repair. Postoperative material from 20 patients with gliomas of different grades of anaplasia was analyzed.

Target Delineation in High-grade Glioma Do CTV Margins Make a Difference? ESTRO ACROP versus RTOG Guidelines a Comparative Dosimetric Study

Background and purpose:There exist two major consensus guidelines for target delineation in glioblastoma(GBM).Namely the established radiation therapy oncology group(RTOG)and the recently redefined European society for radiation oncology(EORTC)-advisory committee on radiation oncology practice(ACROP),clinical studies evaluating the pattern of recurrence with relation to the CTV margins have as of date not evidenced statistically significant difference in relation to the two guidelines.However,considering the standardization of concurrent chemo-radiation with Temozolomide nearly 20%off patients can be expected to survive 2years or beyond.Quality of life issues will play a higher role in defining the better protocol.In the current study,we have dosimetrically compared these guidelines in both perspectives.Material and methods:Thirty patients of GBM who had been planned for conformal radiotherapy during Jan 2017 to Feb 2019 were considered.Each patient dataset contoured with ESTRO-ACROP guidelines to create PLAN A and RTOG guidelines to create PLAN B.Both plans were compared to evaluate the volumetric difference in terms of PTV and the relative proximity to critical normal structures.Results:The median volume of brain irradiated to high doses(60Gy)was significantly greater in PLAN B,566cc vs 398 cc(P<0.0002).The organs at risk were better spared with PLAN A in terms of encroachment of high dose PTV volume.This achieved significance for Brainstem(P<0.01),Chiasma(P<0.04)and hippocampus(P<0.016).We were able to identify patients with PTV volume>400cc and with tumor in Parietal or Temporal regions wouldn’t benefit from PLAN A.Conclusion:The use of target delineation based on a single step plan,excluding expanded edema(ESTRO-ACROP)could potentially reduce high dose target volumes and significantly spare brainstem,optic-chiasma,and hippocampus.Patients with tumor volume<400 cc and frontal lesions are most likely to benefit.