Stereotactic radiosurgery of the postoperative resection cavity for brain metastases

Int J Radiat Oncol Biol Phys. 2008 Jan 1;70(1):187-93. doi: 10.1016/j.ijrobp.2007.06.068. Epub 2007 Sep 19.


Purpose: The purpose of this study was to analyze results of adjuvant stereotactic radiosurgery (SRS) targeted at resection cavities of brain metastases without whole-brain irradiation (WBI).

Methods and materials: Patients who underwent SRS to the tumor bed, deferring WBI after resection of a brain metastasis, were retrospectively identified.

Results: Seventy-two patients with 76 cavities treated from 1998 to 2006 met inclusion criteria. The SRS was delivered to a median marginal dose of 18.6 Gy (range, 15-30 Gy) targeting an average tumor volume of 9.8 cm(3) (range, 0.1-66.8 cm(3)). With a median follow-up of 8.1 months (range, 0.1-80.5 months), 65 patients had follow-up imaging assessable for control analyses. Actuarial local control rates at 6 and 12 months were 88% and 79%, respectively. On univariate analysis, increasing values of conformality indices were the only treatment variables that correlated significantly with improved local control; local control was 100% for the least conformal quartile compared with 63% for the remaining quartiles. Target volume, dose, and number of sessions were not statistically significant.

Conclusions: In this retrospective series, SRS administered to the resection cavity of brain metastases resulted in a 79% local control rate at 12 months. This value compares favorably with historic results with observation alone (54%) and postoperative WBI (80-90%). Given the improved local control seen with less conformal plans, we recommend inclusion of a 2-mm margin around the resection cavity when using this technique.

Publication types

  • Evaluation Study

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Analysis of Variance
  • Brain / surgery*
  • Brain Neoplasms / mortality
  • Brain Neoplasms / surgery*
  • Cranial Irradiation / methods
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Radiation Dosage
  • Radiosurgery / methods*
  • Retrospective Studies
  • Salvage Therapy / methods
  • Treatment Outcome