SeOuL cOhort of Brain Tumor MONitoring Study (SOLOMON)

Inclusion Criteria for retrospective cohort * Patients with radiologically diagnosed brain neoplasm of CNS WHO grade 2 or less since 1998 * Asymptomatic at first visit to the hospital * Patients who, based on the up-to-date knowledge, did not necessarily require immediate treatment at the first hospital visit * Patients who have had two or more MRs at least 3 months apart * No previous radiotherapy or radiosurgery for the brain lesion * 18 years old or more Inclusion Criteria for prospective cohort * Patients with newly diagnosed brain neoplasm of CNS WHO grade 2 or less * Asymptomatic at first visit to the hospital * Patients who, based on the up-to-date knowledge, did not necessarily require immediate treatment at the first hospital visit and who are going to take follow-up MR exams * No previous radiotherapy or radiosurgery for the brain lesion * 18 years old or more * Patients who agree to participate by written consent Exclusion Criteria * Patients who lost follow-up before the second MR exam * Patients requiring immediate treatment due to worsening of symptoms within 3 months of the first MR exam * Patients suspected to have other than a neoplasm at follow-up MR exams