Abstract. In the present study, the efficacy and clinical outcomes of stereotactic aspiration combined with the Gamma Knife radiosurgery (GKRS) method were evaluated retrospectively for patients with large cystic brain metastases. This combined method aims to decrease the tumor weight (volume) and increase the possible radiation dose. The present study involved 48 patients who were diagnosed with cystic metastatic brain tumors between January 2008 and December 2012 in the Department of Neurosurgery of Nanfang Hospital Southern Medical University (Guangzhou, China). Every patient underwent Leksell stereotactic frame, 1.5T magnetic resonance imaging (MRI)-guided stereotactic cyst aspiration and Leksell GKRS. Subsequent to the therapy, MRI was performed every 3 months. The results indicated that 48 cases were followed up for 24-72 months, with a mean follow-up duration of 36.2 months. Following treatment, 44 patients (91.7%) exhibited tumor control and 4 patients (8.3%) experienced progression of the local tumor. During this period, 35 patients (72.9%) succumbed, but only 2 (4.2%) of these succumbed to the brain metastases. The total local control rate was 91.7% and the median overall survival time of all patients was 19.5 months. The 1-year overall survival rate was 70.8% and the 2-year overall survival rate was 26.2%. In conclusion, these results indicated that the method of stereotactic cyst aspiration combined with GKRS was safe and effective for patients with large cystic brain metastases. This method is effective for patients whose condition is too weak for general anesthesia and in whom the tumors are positioned at eloquent areas. This method enables patients to avoid a craniotomy, and provides a good tumor control rate, survival time and quality of life.
IntroductionIn the clinical setting, metastatic tumors that translocate from the primary tumor site to the central nervous system are the most frequently occurring intracranial tumors (1). Three methods, including stereotactic radiosurgery, general surgery and whole-brain radiation therapy (WBRT), are normally clinically used and are relatively effective for treating brain metastases (1). However, for a long time, none of these methods was assigned as the standard therapy in clinical practice. The median survival time of affected patients is 1-3 months without therapy (1). The median survival time increases to ~6 months after WBRT (2) and to 10 months subsequent to using the Gamma Knife radiosurgery (GKRS) method (3). The survival time has been recorded as 12 months in patients who underwent surgery (prior method) and WBRT (4). With each of the latter methods, the patients only suffered from single brain metastasis, however, when using the GKRS and WBRT combined method for multiple brain metastases, a survival time of >1 year can also be obtained (5). Recently, the radiosurgery method has become a focal topic in the area of brain tumor metastases, and more advantages have been demonstrated when compared to tumor resection. Radiosurgery has been applied in m...