Stereotactic Radiosurgery in the Management of Brain Metastasis

Michael L. Smith, M.D.; John Y. K. Lee, M.D.


Neurosurg Focus. 2007;22(3) 

In This Article

Complications of SRS

Reported complications of SRS include peritumoral edema, radiation-induced necrosis, tumoral hemorrhage, and radiation-induced neoplasia. In a review of 264 brain metastases treated in 189 patients, Chang and coworkers[10] reported a 6.4% rate of hemorrhage within 2.5 months of treatment with SRS. In half of these cases of hemorrhage corrective surgical treatment was required. The authors also noted a 3.8% rate of significant peritumoral edema, and in half of these cases, too, the patients had to undergo resection. The study by Chang et al. included renal cell carcinomas, melanomas, and sarcomas only.

Lutterbach et al.[26] evaluated responses to treatment with SRS in 101 patients harboring metastases of various histological subtypes and noted complications in 13 patients. Some of these complications occurred within the first month (worsened seizures or transiently worsened neurological deficits) and some arose between 5 and 26 months posttreatment (such as fixed neurological deficits or radiation necroses). Radiation-induced necrosis can be difficult to manage because standard imaging characteristics do not distinguish reliably between necrosis and residual or recurrent tumor at the treatment site. Advanced imaging modalities, such as MR spectroscopy, can help differentiate between the two and may assist in further treatment decisions.[11]

Radiation-induced neoplasia has been described after SRS. Meningiomas have been documented to grow in arteriovenous malformation treatment beds.[47] Malignant progression of benign lesions treated with SRS is another problem, although deciphering treatment effect from natural history can be difficult.[25] Although radiation-induced neoplasia must be considered when recommending SRS for benign tumors or curable vascular lesions, it is less important for patients with brain metastases. These lesions are already malignant, and the patient's life expectancy is short relative to the normal time frame for this complication. One case report describes the development of an anaplastic astrocytoma 5 years after SRS treatment of metastatic melanoma. The authors reiterate the very low incidence of radiation-induced neoplasia after SRS.[28]


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: