Radiation therapy when combined with surgery is of palliative value in the treatment of astrocytomas of all grades, a Mayo Clinic study indicates.
Alfred Uihlein, MD, Section of Neurologic Surgery, said the comparative study showed radiation therapy to be most effective against high-grade (grades 3 and 4) tumors, and that higher radiation doses (3,500 rads [r] or more) were more effective than lower radiation levels.
The report which was read at the seventh Symposium Neuroradiologicum in September in New York, involved 371 patients with verified supratentorial astrocytomas of all grades. Of that number, 56 (15.1%) died in the early postoperative period. Surviving patients included 161 who were treated by surgery alone and 154 who received surgery and radiation therapy. Survival data are based on 151 of the surgical patients and 151 of the surgical-radiation therapy patients. The remainder were lost to follow-up.
"The three-year and five-year survival rates of the