title: Comparative risk of leptomeningeal dissemination of cancer after surgery or stereotactic radiosurgery for a single supratentorial solid tumor metastasis.
abstract: OBJECTIVE
  To test the hypothesis that differential risks of developing leptomeningeal disease (LMD) exist in patients having a single supratentorial brain metastasis resected via a piecemeal or en bloc approach or treated with stereotactic radiosurgery (SRS).
  
  
  METHODS
  Between 1993 and 2006, 827 patients with a supratentorial brain metastasis underwent resection or SRS at The University of Texas M.D. Anderson Cancer Center. The primary outcome was the incidence of LMD.
  
  
  RESULTS
  Resection was performed piecemeal in 191 patients and en bloc in 351 patients; 285 patients received SRS. LMD occurred in 33 patients, 29 in the resection group and 4 in the SRS group. Risk of LMD was significantly higher with piecemeal tumor resection than with other procedures (SRS: hazard ratio [HR] for piecemeal, 5.8; 95% confidence interval [CI], 1.9-17.2; P = 0.002; en bloc, HR for piecemeal, 2.7; 95% CI, 1.3-5.6; P = 0.009). The difference between piecemeal and en bloc was particularly pronounced in patients with a melanoma primary (HR, 8.4; 95% CI, 1.8-39.2; P = 0.007). The risk of LMD was not significantly different between en bloc resection and SRS (HR for en bloc, 2.1; 95% CI, 0.7-6.4; P = 0.21). Similar results were obtained when comparing effects of SRS and both resection approaches after limiting the sample to patients with tumors in a specific volume range.
  
  
  CONCLUSIONS
  Piecemeal resection of a supratentorial brain metastasis carries a higher risk of LMD than en bloc resection or SRS. Further assessment of the role of the 2 surgical resection approaches and SRS in a controlled prospective setting with large numbers of patients is warranted.
authors.affiliation: Department of Neurosurgery, The University of Texas M.D. Anderson Cancer Center, Houston, Texas, USA. dsuki@mdanderson.org
authors.forename: Dima
authors.initials: D
authors.lastname: Suki
authors.forename: Mustafa Aziz
authors.initials: MA
authors.lastname: Hatiboglu
authors.forename: Akash J
authors.initials: AJ
authors.lastname: Patel
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Weinberg
authors.forename: Morris D
authors.initials: MD
authors.lastname: Groves
authors.forename: Anita
authors.initials: A
authors.lastname: Mahajan
authors.forename: Raymond
authors.initials: R
authors.lastname: Sawaya
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000528:radiation effects; D015331:Cohort Studies; D003399:Craniotomy / Q000009:adverse effects; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008577:Meningeal Neoplasms / Q000556:secondary* / Q000601:surgery; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000009:adverse effects; D016634:Radiosurgery / Q000009:adverse effects*; D012189:Retrospective Studies; D012307:Risk Factors; D015173:Supratentorial Neoplasms / Q000473:pathology* / Q000601:surgery*; D055815:Young Adult