— Archie, patient. Understanding Brain Tumors. CHAPTER TWO / UNDERSTANDING BRAIN TUMORS CHAPTER 2 / ... 550,000 WITH BENIGN TUMORS Source: CBTRUS Statistical Report (2012) PRIMARY BRAIN . TUMOR TYPES 16% Glioblastoma: 7 % Astrocytoma: 35 % Meningioma: 14 % Pituitary: 9 % Nerve Sheath: 2 % Lymphoma: 33 % Other.