Clinical Outcomes of Gamma Knife Radiosurgery for Metastatic Brain Tumors from Gynecologic Cancer : Prognostic Factors in Local Treatment Failure and Survival

Objective : Brain metastases in gynecologic cancer ( ovarian, endometrial, and cervical cancer) patients are rare, and the efficacy of Gamma Knife Radiosurgery ( GKRS) to treat these had not been evaluated. We assessed the efficacy of GKRS and prognostic factors for tumor control and survival in brain metastasis from gynecologic cancers. Methods : This retrospective study was approved by the institutional review board. From May 1995 to October 2012, 26 women ( mean age 51.3 years, range 27-70 years) with metastatic brain tumors from gynecologic cancer were treated with GKRS. We reviewed their outcomes, radiological responses, and clinical status. Results : In total 24 patients ( 59 lesions) were available for follow-up imaging. The median follow-up time was 9 months. The mean treated tumor volume at the time of GKRS was 8185 mm(3) ( range 10-19500 mm(3)), and the median dose delivered to the tumor margin was 25 Gy ( range, 10-30 Gy). A local tumor control rate was 89.8% ( 53 of 59 tumors). The median overall survival was 9.5 months after GKRS ( range, 1-102 months). Age-associated multivariate analysis indicated that the Karnofsky performance status ( KPS), the recursive partitioning analysis ( RPA) classification, and the number of treated lesions were significant prognostic factors for overall survival ( HR= 0.162, p= 0.008, HR= 0.107, p= 0.038, and HR= 2.897, p= 0.045, respectively). Conclusion : GKRS is safe and effective for the management of brain metastasis from gynecologic cancers. The clinical status of the patient is important in determining the overall survival time.