Plenary Oral Presentations - Macquarie University Hospital

16 th International Meeting of the Leksell Gamma Knife ® SocietyMarch 2012, Sydney, AustraliaMA-117One-day aspiration/GKS procedure is effective for metastaticbrain tumor with cystic component.Fumi Higuchi, Shunsuke Kawamoto, Keisuke Ueki, Phyo KimDepartment of Neurosurgery,Dokkyo University School of MedicineObjective: GKS is an effective tool for the treatment of metastatic brain tumors. It covers multiplelesions in a single procedure and is less stressful for the patient. However, the tumor size amenable toGKS is limited to less than 3 cm in diameter, and cystic tumors frequently exceed this size limitationeven if the solid portions are small. In order to avoid lowering the prescription dose sufficient for tumorcontrol, the target volume should be decreased as much as possible. For such lesions, we adopted a newstrategy of performing stereotactic cyst aspiration prior to GKS on the same day. We investigated itsefficacy in reducing target volume and tumor control.Methods: Stereotactic aspiration followed by GKS was performed for 26 metastatic brain tumors in25 patients at Department of Neurosurgery Dokkyo Medical University from February 2005 to April2010.Their medical records were retrospectively reviewed. We collected data on target tumor volumesbefore and after aspiration, local control of the tumor and patients’ outcomes.Results: The patient’s ages ranged 32 to 77 years (mean 58). Mean target volume was reduced from20.0 cm3(range 8.0- 64.2 cm3 ) to 10.3 cm3 (range 8.0- 64.2 cm3) after aspiration. Volume reductionwas approximately 50 %. Before aspiration there were 13 lesions exceeding 14 ml in volume, whichis equivallent to a 3cm sphere. In 7 out of these 13 lesions, the target volume was reduced to lessthan 14ml by aspiration. Prescription dose ≥ 20Gy was achievable in all except one case. Follow upperiods were 1-27 months (median11). Seventy-six percent of tumors were well controlled at the endof the follow up or at the patient’s death by other causes. The 1- and 2-year actuarial survival rate was43.1% and 14.4%.Conclusions: One-day aspiration/GKS is effective for brain metastases with cystic component.Aspiration procedure reduces the tumor volume significantly, and thereby warrants satisfactorytumor control by enabling safe delivery of sufficient treatment dose.38