Brain Masses

Brain Masses


  • Neoplasm is the biggest concern: ~ 90% of malignant brain masses are metastatic
  • Other etiologies: abscess, tumefactive demyelinating lesions, vascular malformations, sometimes other causes of edema (e.g. paraneoplastic)
  • Most common metastatic brain tumors: lung, RCC, breast, and melanoma
  • Tumors with high bleeding risk: melanoma, thyroid, choriocarcinoma, and RCC
  • Gliomas: WHO Grade I-IV, with IV being glioblastoma multiforme (GBM)
    • GBM appears as large heterogeneous masses with edema; heterogenous contrast enhancement; can cross the corpus callosum
    • Lower grade gliomas, which includes oligodendrogliomas and astroytomas
  • Meningioma – usually low grade and either left alone and monitored, but can be symptomatic in which they are resected/radiated
  • Ependymoma – uncommon, usually lower grade can cause CSF outflow obstruction
  • CNS lymphoma – diffuse WM involvement, with mass effect, restricts diffusion on MRI with prominent contrast enhancement. Can also cross the corpus callosum
    • Usually B-cell, initially responds significantly to steroids



  • A significant number of brain lesions are detected incidentally
  • If a pt has a first-time seizure, brain mass needs to be ruled out
  • HA (usually constant, severe), seizure and focal neurologic deficits



  • Imaging: MRI w/ and w/o contrast provides the most information
    • Findings suggesting malignant lesions: marked edema, multifocal lesions, or presence at gray-white junctions
  • LP may be indicated if herniation risk is low, particularly if concerned for infection
  • Biopsy will ultimately be needed in most cases, which is done through NSGY



  • Work up for primary malignancy, CT C/A/P + PET
  • Steroids are generally indicated for treatment of edema
    • Decadron 10 mg IV to start; then transition to 4mg IV q6h with SSI
  • If seizure develops would treat as outlined in seizure section
  • Symptomatic tumors need eval by NSGY for resection consideration
  • Other options include radiation, which does happen as inpatient but it is rare