Stereotactic radiotherapy for solitary brain metastases

Purpose: Surgery is considered to be the treatment of choice for patients w ith solitary brain metastases. We report a single-centre experience of ster eotactic radiotherapy (SRT)/radiosurgery as an alternative to surgery and d efine prognostic parameters that provide for a more rational selection of p atients for appropriate treatment. Patients and Methods: Between 1990 and 1997, 96 patients with 106 brain met astases received SRT to a dose of 20 Gy in two fractions (range 20-30 Gy in 2-4 fractions) either alone or in combination with whole brain radiotherap y. Results: After SRT, 51% of patients had improvement in neurological functio n. The median survival of the 96 patients was 9 months. The Radiation Thera py Oncology Group prognostic grouping for patients with multiple brain meta stases (prognostic factors: age, performance status, systemic metastases, s tatus of primary tumour) was applicable to this cohort, with median surviva ls of 15, 8 and 2 months for favourable, intermediate and poor prognostic g roups respectively. Conclusion: SRT is a non-invasive method of treatment of solitary brain met astases and the outcome is comparable with the results obtained after surgi cal excision. Prognosis is determined by factors defined for patients with multiple brain metastases, with performance status being the most important . SRT/radiosurgery should be reserved for patients with favourable prognost ic factors, with a Karnofsky performance status > 70, who have a reasonable chance of good quality prolonged survival. In future trials, radiosurgery should be compared in terms of survival, quality of life and health economi cs to whole brain radiotherapy and surgery.