General Introduction

Abstract

Intracranial tumors are generally classified into either primary or secondary tumors, accounting for 1–2% of all adult malignancies. Primary tumors may originate from brain tissue, meninges, cranial nerves, blood vessels, pituitary gland, embryonic remnant tissue, etc. Secondary tumors develop when malignant tumors metastasize or invade into the brain from other organs. Intracranial tumors can occur at any age, mainly at the age of 20–50 years. In children and adolescents, tumors are more common in the midline of the posterior fossa, such as medulloblastoma, craniopharyngioma, and pineal area tumors. Glioma is commonly seen in adult patients, followed by meningioma, pituitary tumor, schwannoma, primary central nervous system lymphoma, etc. In elderly patients, glioma and brain metastases are common. There was no significant gender difference in the incidence of primary intracranial tumors. Intracranial tumors have a poor prognosis, hence being the second cause of death in adult neurological diseases. The morbidity and mortality of children’s brain tumors are the second most common systemic tumors in children.