Validated method for automated glioma diagnosis from GFAP immunohistological images: a complete pipeline

Background and objective: Glial fibrillar acid protein is a common marker for brain tumor because of its particular rearrangement during tumor development. It is commonly used in manually histological glioma detection and grading. An automatic pipeline for tumor diagnosis based on GFAP is proposed in the present manuscript for detecting and grading canine brain glioma in stages III and IV. Methods: The study was performed on canine brain tumor stages III and IV as well as healthy tissue immunohistochemically stained for gliofibrillar astroglial protein. Four stereological indexes were developed using the area of the image as reference unit: density of glioma protein, density of neuropil, density of astrocytes and the glioma nuclei number density. Images of the slides were subset for image analysis (n=1415) and indexed. The stereological indexes of each subset constituted an array of data describing the tumor phase of the subset. A 5% of these arrays were used as training set for decision tree classification with PCA. The other arrays were further classified in a supervised approach. ANOVA and PCA analysis were applied to the indexes. Results: The final pipeline is able to detect brain tumor and to grade it automatically. Added to it, the role the neuropil during tumor development has been quantified for the first time. While astroglial cells tend to disappear, glioma cells invade all the tumor area almost to a saturation in stage III before reducing the density in stage IV. The density of the neuropil is reduced during the tumour growth. Conclusions: The method validated ere allows the automated diagnosis and grading of glioma in dogs. This method opens the research of the role of the neuropil in tumor development.

Role of Susceptibility Weighted Images (SWI) in Grading of Brain Glioma

Background Glioma is the most common intracranial primary tumor of central nervous system (CNS) and accounts for about 70% of primary adult malignant brain tumors. The optimum therapeutic treatment and prognosis evaluation largely depends on the tumor pathological grades. Objective To evaluate the role of susceptibility weighted imaging (SWI) in grading of cerebral gliomas. The magnetic resonance imaging (MRI) results were compared and correlated to the pathology results to evaluate its role. The pathological grading of the glioma was done according to WHO 2007 classification system. Patients and Methods This was a retrospective study that included 35 adult patients, (11females & 24 males), their ages ranging from 18 years to 73 years. They were pathologically proven glioma patients ranging from grade I to grade IV. All the patients were referred from neurosurgeon to our radiology center (private center). This study was carried out during the period between January 2017 and November 2018. Results In our study, there were a strong positive correlation between both conventional imaging and pathological grading and between pathological and SWI grading. Using SWI sequence in grading of glioma will be very beneficial in patients with contraindication to contrast. Conclusion SWI using 3T MR system may provide quite useful information for preoperative glioma grading. There seems to be a strong positive correlation between pathological grading and SWI grading system for glioma. The main disadvantage for SWI is the extra time added to the usual time of routine MRI protocol used in cases of intra cranial space occupying lesions (SOL).