Evaluation of h3k27me3 expression in different anatomical localisations and different histologic subtypes in meningioma cases, its correlation with recurrence and other prognostic parameters

WHO classification of meningiomas has many limitations in predicting meningiomas' behaviour and prognosis, The diagnostic potential of H3k27me3 has been demonstrated for many tumours. This study aimed to evaluate the expression of h3K27me3 in various anatomical localizations and various histologic subtypes of meningioma, as well as to determine the link between its expression and recurrence and free recurrence survival time. 112 cases from 2015 to 2022 were recruited from Goztepe Medical Park hospital, H3K27me3 was assessed by Immunohistochemistry, the cases were prepared and H3K27me3 was applied, Expression of H3K27me3 was assessed by two physicians, the data were collected, coded, and statistically analysed. Most cases of meningioma retained more than 50% of H3K27me3 and no case showed total loss of expression. However, the difference of expression of H3K27me3 was not statistically significant neither among different WHO grades of meningioma (P=.211) nor among meningiomas in different localisations (.953) nor among different histologic subtypes of meningioma (.879). The expression of H3K27me3 was not different between de novo and recurrent meningiomas (.932). Loss of H3K27me3 was not a risk factor for the incidence of recurrence, and it was not associated with free recurrence survival in meningioma. Overall, H3K27me3 expression does not seem to be beneficial in the clinical diagnosis of meningioma. Moreover, it did not seem to show any potential to become an investigatory tool to determine the prognosis of meningioma.