In Reply: MicroRNA Analysis in Meningiomas With Different Degrees of Tissue Stiffness: A Potential Tool for Effective Preoperative Planning

To the Editor: We are very pleased that you have given us the space to comment on the Letter sent by Jiale Li, Lexin Wang, and Hao Chi.1 We view this critique positively and thank the authors for it. We are aware of all the limitations mentioned and have discussed some of them in our paper.2 A prospective study is currently underway at our institution to answer some of these outstanding questions. In addition to the already ongoing collection of tumor tissues from patients with meningiomas, we also collect cerebrospinal fluid from the patient after signing an informed consent before surgery, which, based on our experience and the literature, seems to be a more suitable source of biomarkers in brain tumors compared with peripheral blood.3 Our department has experience with the analysis of microRNAs in this body fluid using both reverse transcription–quantitative polymerase chain reaction and next-generation sequencing technologies.4,5 This study is planned as a single center, and we plan to enroll 150 patients in the first phase; based on our experience to date, we anticipate 78% WHO grade I and 20% WHO grade II meningiomas. Thereafter, an interim analysis will be performed and consideration will be given to further addition of patients to the study if necessary. Unfortunately, the problem of under-representation of WHO grade III patients will persist and it is not possible to enroll sufficient numbers of patients with this grade of disease for a separate and sufficiently powered statistical evaluation within the time frame dedicated to this prospective study within our neurosurgical center. However, we believe that the aim of our study does not necessarily require this and that the results obtained on the whole cohort will be sufficiently conclusive and, above all, clinically relevant. We are also aware that imaging methods can significantly increase the predictive value of molecular analyses, and therefore, all patients consecutively enrolled in the study are evaluated at the Department at Radiology and Nuclear Medicine using MRI techniques including diffusion-weighted imaging. In conclusion, we would like to once again thank the authors for their comments, and we hope that the results of our prospective study will answer most of them, thus enabling neurosurgeons to create more accurate preoperative plans and ultimately leading to an improved quality of life for patients with meningiomas.