What is the Forecast for Brain Metastases?

Historically, a diagnosis of metastasis to the brain was considered the beginning of the end. Even with the use of steroids to prevent or treat the symptoms, most patients were given only a few months to live [1]. Even now, the estimated patient lifespan after a brain metastasis diagnosis can be hard to predict. Clinicians experienced in brain metastases have been reported to be incorrect by as much as 12 to 18 months when forecasting individual patient survival [2].

Brain metastases themselves can also be hard to predict. Once in the brain, metastases can grow quickly and can crowd or destroy nearby brain tissue. A patient may have many brain metastases in several different areas of the brain. Metastatic brain tumors can appear many years after the primary cancer. Others grow so quickly that they are diagnosed before the primary cancer. In some cases, the body is able to destroy the primary cancer but not the metastatic brain tumor. The chance of a poor outcome begins to increase in people ages 50 to 65 and is highest in those over 65 [3]. Regardless of age, brain metastases could justify an aggressive treatment.

In the past, aggressive treatment of brain mets was thought to be of little value after such an unwelcomed diagnosis. Even today, approximately half of all patients with brain mets die within seven months of diagnosis [4]. There are, however, aggressive treatment options that promise effective treatment of this disease [5].

See How are Brain Metastases Treated for an overview of treatment options.

[1] Sawaya, R. E. Intracranial Metastases. Book (Blackwell Publishing, Inc., 2004). doi:10.1002/9780470753064
[2] Kondziolka, D. et al. The accuracy of predicting survival in individual patients with cancer. J. Neurosurg. 120, 24–30 (2014).
[3] Sperduto, P. W., Berkey, B., Gaspar, L. E., Mehta, M. & Curran, W. A new prognostic index and comparison to three other indices for patients with brain metastases: an analysis of 1,960 patients in the RTOG database. Int. J. Radiat. Oncol. Biol. Phys. 70, 510–4 (2008).
[4] Sperduto, P. W. et al. Diagnosis-specific prognostic factors, indexes, and treatment outcomes for patients with newly diagnosed brain metastases: a multi-institutional analysis of 4,259 patients. Int. J. Radiat. Oncol. Biol. Phys. 77, 655–61 (2010).
[5] Kim, D. & Lunsford, L. Current and Future Management of Brain Metastasis. Book 25, (Karger Publishers, 2012).