STEREOTAXIC IRRADIATION WITHOUT WHOLE-BRAIN IRRADIATION FOR SINGLE BRAIN METASTASIS

Purpose: The effectiveness of stereotactic irradiation (STI) alone wit hout whole-brain irradiation (WBI) for a single metastatic brain tumor was analyzed retrospectively. Methods and Materials: Forty-four patie nts with this condition were treated using radiosurgery (RS) alone or fractionated stereotactic radiotherapy (FSR) without WBI. Results: The initial response rate was 92% and the overall local control rate was 84% (37 of 44 patients), A total of 39% (18 of 34) of patients experie nced intracranial relapse outside the initial target area, Forty-eight percent (21 of 44) of patients required salvage treatment for intracr anial relapse. All 7 patients who received WBI as salvage treatment re quired no further salvage treatment, but 5 of the 14 patients who rece ived salvage STI without WBI required three to four treatments for bra in metastasis, Late radiation damage was not seen with initial treatme nt but was observed with retreatment. The overall median survival time was 261 days, with a standard error of 64 days, Actuarial survival at 12 and 24 months was 34% and 9%, respectively, The actuarial survival rate was significantly affected by the existence of active extracrani al disease (p = 0.041). Conclusion: The high response rate and short t reatment period of STI alone are advantageous in the treatment of sing le brain metastasis in patients with active extracranial disease with WBI reserved for relapse, Because of the low complication rate, STI al one may be also useful in patients with good prognosis, without extrac ranial disease. (C) 1997 Elsevier Science Inc.