Investigation of TERT promoter mutation by molecular methods and determination of its prognostic value for meningiomas

The two most important parameters used in determining the risk of recurrence and progression and predicting the prognosis in meningiomas are histopathological grade and extension of surgical excision. In addition to these two major parameters, there are some recent studies show that the presence of TERT promoter mutation may have prognostic importance in meningiomas. Our aim is to examine the relationship between TERT promoter mutation and the biological behavior of the tumor and its prognostic significance in this study. Moreover, providing data to the literature for studies on targeted therapy agents is also our goal for this study. In this retrospective study, we selected 165 meningioma cases from the archive of Akdeniz University Department of Pathology. Tumor slides were reevaluated and regraded according to the criteria of the 2016 WHO (World Health Organization) classification of tumors of the CNS (Central nervous system). A real-time PCR technique was performed on selected FFPE tumor tissues to search for TERT promoter mutation. Then, the relationship between TERT promoter mutation status and clinical and histopathological features of the patients was evaluated and survival analysis was performed. TERT promoter mutation was detected in 11 (7%) of 165 patients. As a result of the analysis, a statistically significant relationship was observed between survival time and high histopathological grade and advanced patient age in meningiomas. These results were compatible with the literature. However, the relationship between TERT promoter mutation status and recurrence rate, progression rate, time to the first recurrence, and overall survival was not statistically significant contrary to what was pointed out in previous reports. One of the most likely reasons for this situation might be the low number of patients with TERT promoter mutation and the low number of patients with anaplastic meningioma in our study. In conclusion, our results showed that the presence of TERT promoter mutation in meningiomas might be associated with a poor prognosis. But to elucidate the prognostic importance of TERT promoter mutation and obtain satisfactory statistical results in meningiomas, multicenter studies with large patient series are needed. Keywords: TERT, promoter, meningioma, recurrence, prognosis