Irradiation of primary brain-stem tumors.

Of 40 patients treated for brain-stem tumors, 20 had lesions of the thalamus and midbrain (group A) and 20 had lesions of the pons and medulla (group B). Performance status measured 1 month after irradiation improved in 16 of 20 group A and 11 of 20 group B patients and was a valuable prognostic factor. The survival rate at 5 years was 40% (8/20) in group A and 30% (6/20) in group B. All recurrences appeared within 3 years and were predominantly locoregional. Treatment factors, including dose and field size, are analyzed.