The correlation between radiological features and histopathological findings among patients with intracranial meningiomas in Eldoret, Kenya

Abstract

Background: Meningiomas are amongst the commonest primary brain tumours accounting for about 33% of all brain tumours. World Health Organization classifies meningiomas into three grades based on histopathology; the subtype of which affects the prognosis. Imaging plays a key role in the diagnosis of meningiomas and is often the first investigation aiding in its diagnosis. This study aims to establish if there is a correlation between histopathology and the radiological features of meningiomas. Setting: The study was done at the Moi Teaching and Referral Hospital, Mediheal and Eldoret hospitals in Eldoret, Kenya. Objective: To assess the radiological features of intracranial meningiomas in correlation to their histopathological findings among patients in Eldoret, Kenya. Design: A cross-sectional study design was used. Methods: Radiopathological correlation was done using CT scan and MRI images which had a confirmatory histopathology report. 55 patients were studied from May 2008 to December 2012.Consequctive data sampling technique was done. An inclusion criterion was presence of both histopathology and CT or MRI images while exclusion was where either lacked. Data was collected by using a data collection form and analysis was done by STATA version 12. Results: The female to male ratio was 3:1. The mean age was 47 years. The age group most affected was 45-55 years. The common CT scan features encountered were extra-axial, hyperdense (87%), mass lesions (98%) with mild (36%) to moderate oedema (45%) that avidly enhanced with contrast either homogenously (47%) or heterogeneously (53%). Common MRI features encountered were extra-axial mass lesions (97%) which were isointense (61%) on T1 weighted sequences, hyperintense (65 %) on T2 weighted images, hyperintense (65%) on FLAIR images and enhanced (100%) when gadolinium contrast was injected. The common meningiomas encountered were grade I (95%) with the meningothelial (53%), fibroblastic (22%) and transitional (20%) subtypes seen. 3 grade II atypical meningiomas were found but no malignant meningioma was encountered in the study population. Correlation between the various radiological features and histopathology was only seen with the CSF variable and this was likely a chance finding. Conclusion and Recommendations: Though imaging can reliably diagnose meningiomas, histopathological subtypes of meningiomas cannot be differentiated from each other based on radiological features. Further studies should be done on non-benign meningiomas which were few in this study and why secondary changes common in benign meningiomas. Histopathology should be improved by doing immunohistochemistry.