Dr. Sawaya provides a comprehensive review and citation of the key references that have shaped the current management of cerebral metastases. The reader is directed to the importance of this aspect of cancer management by carefully documented sections that center on the epidemiology of these lesions.
In ruminating on the information in Dr. Sawaya’s review and the comments that follow, it must be recognized that the management of cerebral metastases varies, depending on the timing of the needed intervention, and certain variables obviate the ability to make algorithms that are as neat as one might initially wish. Newly diagnosed lesions are approached differently than recurrent or progressive disease, depending on prior treatment and the current systemic health of the patient.
Threshold for Investigation of Symptoms
As in all aspects of cancer management, early detection of a tumor or its subsequent progression is key to effective intervention. Although there is a sense that central nervous system (CNS) involvement is such an adverse development prognostically that some clinicians may not pursue evaluation of neurologic symptoms, the data provided in this review suggest that a number of treatment options are available.
Therefore, individuals with established cancers, particularly cancers prone to involve the CNS (such as lung and breast cancer and melanoma), warrant careful observation for the onset of neurologic symptoms or focal neurologic deficits. In patients with previously confirmed CNS involvement, regular clinical and imaging follow-up is critical to early detection of progression.
MRI in Screening, Diagnosing, and Managing CNS Metastases
Magnetic resonance imaging (MRI) scans of the brain and spine have proven to be the most effective means of screening individuals with headaches, seizures, or new focal cranial nerve, motor, sensory, or coordination deficits suspected to be caused by a tumor. The use of a contrast agent is key to this type of study. For intraparenchymal lesions, MRI frequently provides all the information necessary to make treatment decisions.