Purpose: To evaluate the usefulness of radiosurgery without whole brain irradiation for a solitary brain metastasis.
Patients and methods: Between December 1994 and November 1996, 12 patients were treated for a single brain metastasis by radiosurgery alone. Median age was 53, and 10 patients had a Karnofsky performance status above 70. Half the patients had active extracranial disease at the time of radiosurgery. Stereotactic radiosurgery delivered a single dose of 20 Gy (specified at the isocenter with a 70% isodose reference curve). Evaluation of results was performed according to local control, survival, evolution of performance status, as well as evolution of neurologic symptoms.
Results: No patient had immediate toxicity. One month later, ten patients showed improvement in their neurologic impairments, and none had progression of the cerebral lesion according to CT scan evaluation (diminution for seven patients, and stabilization for five). Local control rate was 58%, and median time to failure was 4 months. The overall median survival time was 10 months. Three patients were alive, with good performance status, and six died following cerebral progression.
Conclusion: These poor results in terms of local control are in favor of supplementary whole brain irradiation, except for particular cases.