Non-malignant central nervous system (CNS) tumor accounts for 70% of all primary CNS tumors, and over 300,000 patients were diagnosed with non-malignant CNS tumor per year in the United States. Not much is known about the natural history of non-malignant CNS tumors, as it is often treated immediately upon detection. However, some of them, especially small and asymptomatic non-malignant CNS tumors should not be treated immediately upon diagnosis but are observed and followed-up by repeated magnetic resonance imaging (MRI). This study aims to make a prospective cohort of non-malignant CNS tumors that do not require immediate treatment and to quantitatively analyze which factors are related to the growth of tumors.~The registry of this study was subjected to patients who were radiologically diagnosed with a non-malignant brain tumor at Seoul National University Hospital since 2001, and who have had MR re-examination after first MR exam or will be re-examined because it was determined that immediate treatment would not be needed at the first visit to the hospital. Non-malignant brain tumors are defined as radiologically diagnosed neoplasms of CNS WHO grade 2 or lower among primary intracranial tumors and include meningioma, schwannoma, pituitary adenoma, and glioma suspected to be non-malignant.
The registry of this study was subjected to patients who were radiologically diagnosed with a non-malignant brain tumor at Seoul National University Hospital since 2001, and who have had magnetic resonance (MR) re-examination after first MR exam or will be re-examined because it was determined that immediate treatment would not be needed at the first visit to the hospital. In all MRs taken by patients, the date of imaging and the volume of the tumor are measured, and we aim to establish a natural growth history for non-malignant brain tumors.