Stereotactic irradiation of solitary brain metastases with Leksell gamma knife

Fifty-three patients (32 men and 21 women) with 75 brain metastases were treated from October 1992 to November 1994. Stereotactic fractionated irradiation (in 2 to 5 fractions) was applied to 19 patients, mostly with larger pathological lesions. The group of solitary brain metastases that is best suited for stereotactic irradiation using the Leksell gamma knife is characterized; this group is primarily determined by the volume of the lesion (average diameter up to 20 mm) and its location in the cerebral hemispheres, age under 60 years, and the Karnofsky score over 70%. Three clinical cases of stereotactically irradiated metastases are described. Although a longer time period (at least 18 months) will be necessary for evaluation of the late effects, the advantages of stereotactic irradiation of brain metastases are evident: a zero mortality on surgery, minimal morbidity, short hospital stay, and minimal demands placed on the patient's lifestyle. (author) 7 figs., 15 refs