By: James I. Ausman, MD, PhD
Brain Metastasis is often regarded with hopelessness, but new advances in Diagnosis and Treatment have changed that opinion.
Brain metastasis occurs in up to 50% of patients with cancer. As new systemic treatments prolong life, brain metastases become more common. Quality of Life (QOL) is the most important goal of treatment.
Often a metastasis to the brain is silent and is found on routine screening after the primary is found. Symptoms of weakness of an arm or leg, speech or visual disturbance, or balance problems are the most common from larger lesions or smaller metastasis located in critical areas. Headache, nausea and vomiting are non-specific symptoms of increased intracranial pressure. Metastases producing symptoms are considered for surgical treatment. Silent metastases are best considered for Stereotactic Radiation Treatment (SRT).
The best imaging modality is contrast enhanced MR, as CT with contrast can underestimate the number of lesions.
Treatment decisions include:
- No Treatment for those with far advanced disease who have a poor prognosis or whose QOL cannot be improved.
- Surgery is best for solitary lesions that are accessible. For larger lesions producing symptoms, radiation therapy is not successful. The goal of surgery is to remove the metastasis totally, which will produce the longest survival. Metastasis to the cerebellum will produce rapid death from increased intracranial pressure unless operated, as the CSF flow is obstructed by the mass and swelling. Radiation often produces more swelling and faster mortality. Removal will provide more time for therapy and even long survivals. In patients with more than one lesion a combination of Surgery and a single treatment of Stereotactic Radiation Therapy can be performed to provide QOL. Surgery can now be done with intraoperative imaging for tumor localization with a high success rate and low morbidity, no mortality, and a short LOS. Surgery is usually followed with Stereotactic Focused Radiation to the tumor cavity to limit recurrence and prolong survival with QOL.
- Whole Brain Radiation Therapy (WBRT), formerly relied on as the standard treatment, produces cognitive deficits in patients. Stereotactic Radiation Therapy (SRT) can be focused on the lesions and produce lesion regression while preserving cognition and Quality of Life. SRT can be used in patients with multiple metastases.
- Chemotherapy is used for the primary lesion and for the metastasis. Much more is known today about the molecular factors leading to the seeding and growth of metastases. Recent new molecular treatments can provide remarkable remissions of brain metastasis in patients who previously failed other measures.
- Dexamethazone, 4mg q6hr is used to reduce the edema associated with brain metastases and can produce rapid symptomatic improvement. Use with proton pump inhibitors. Anti-convulstants are also used prophylactically.
All cancers can metastasize to the brain. With the success of modern therapy, brain metastases are becoming more frequent. The most common tumors to metastasize are lung, breast, renal, and colon cancers, and melanoma.
Patients with leptomeningeal carcinomatosis can be treated with a combination of therapies, including shunting for hydrocephalus or reservoir implantation for intrathecal treatment. Given the many options now available to these patients with brain metastases, a discussion by the referring doctor or the patient with the neurosurgeon is valuable to be able to review all the options now available.
Dr. Ausman is formerly Head of Neurosurgery at Henry Ford Hospital in Detroit, Michigan and at the University of Illinois at Chicago. He is presently Professor of Neurosurgery at UCLA and Harbor–UCLA Medical Centers. He is Editor-in-Chief of Surgical Neurology International, a Free Internet journal of Neurosurgery with the largest circulation in the world, read in 227 countries. (www.sni.global). He can be reached at Desert Spine and Neurosurgical Institute (760) 346- 8058 or at email@example.com. He is also a member of Desert Doctors. For more information visit DesertDoctors.org or call (760) 232-4646.