Neoplastic disorders
     Glioma (more commonly higher grade lesions such as glioblastoma multiforme)
     Metastasis (either extracranial primary tumors or brain-to-brain spread from
       primary glioblastoma multiforme)
     Primitive neuroectodermal tumor (in children)

Infectious disease
     Abscess (especially toxoplasmosis in immunocompromised patients)
     Sarcoidosis
     Tuberculosis
     Other granulomatous diseases