title: Stereotactic drainage and Gamma Knife radiosurgery of cystic brain metastasis.
abstract: OBJECTIVE
  Treatment options for patients with brain metastasis include tumor resection, whole-brain radiation therapy, and radiosurgery. A single treatment is not useful in cases of multiple tumors, of which at least 1 is a cystic tumor. The purpose of this study was to assess the role of stereotactic drainage and Gamma Knife surgery (GKS) in the treatment of cystic brain metastasis.
  
  
  METHODS
  Between January 2001 and November 2005, 680 consecutive patients with brain metastases underwent GKS at our hospital, 30 of whom were included in this study (18 males and 12 females, mean age 60.6 +/- 11 years, range 38-75 years). Inclusion criteria were: 1) no prior whole-brain radiation therapy or resection procedure; 2) a maximum of 4 lesions on preoperative MR imaging; 3) at least 1 cystic lesion; 4) a Karnofsky Performance Scale score >or= 70; and 5) histological diagnosis of a malignant tumor.
  
  
  RESULTS
  Non-small cell lung carcinoma was the primary cancer in most patients (19 patients [63.3%]). A single metastasis was present in 13 patients (43.3%). There was a total of 81 tumors, 33 of which were cystic. Ten patients (33.3%) were in recursive partitioning analysis Class I, and 20 (66.6%) were in Class II. Before drainage the mean tumor volume was 21.8 ml (range 3.8-68 ml); before GKS the mean tumor volume was 10.1 ml (range 1.2-32 ml). The mean prescription dose to the tumor margin was 19.5 Gy (range 12-25 Gy). Overall median patient survival was 15 months. The 1- and 2-year survival rates were 54.7% (95% confidence interval 45.3-64.1%) and 34.2% (95% confidence interval 23.1-45.3%). Local tumor control was achieved in 91.3% of the patients.
  
  
  CONCLUSIONS
  The results of this study support the use of a multiple stereotactic approach in cases of multiple and cystic brain metastasis.
authors.affiliation: Gamma Knife Unit, Department of Neurosurgery, IRCCS San Raffaele, University Vita-Salute, Milan, Italy. franzin.alberto@hsr.it
authors.forename: Alberto
authors.initials: A
authors.lastname: Franzin
authors.forename: Alberto
authors.initials: A
authors.lastname: Vimercati
authors.forename: Piero
authors.initials: P
authors.lastname: Picozzi
authors.forename: Carlo
authors.initials: C
authors.lastname: Serra
authors.forename: Silvia
authors.initials: S
authors.lastname: Snider
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Gioia
authors.forename: Camillo
authors.initials: C
authors.lastname: Ferrari da Passano
authors.forename: Angelo
authors.initials: A
authors.lastname: Bolognesi
authors.forename: Massimo
authors.initials: M
authors.lastname: Giovanelli
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000401:mortality / Q000556:secondary* / Q000601:surgery*; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000556:secondary* / Q000601:surgery*; D003131:Combined Modality Therapy; D004322:Drainage; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011379:Prognosis; D016634:Radiosurgery; D016879:Salvage Therapy; D013238:Stereotaxic Techniques; D016019:Survival Analysis