Between 1970 and 1985, 145 patients were treated for pituitary adenomas and 126 patients were available for analysis. Sixty patients were treated with surgery alone (Group I), 54 were treated with surgery and radiation therapy (Group II), and 12 received irradiation only without tissue diagnosis (Group III). Extent of tumor was evaluated by CT scan, PEG, and surgical reports. There were 22 microadenomas in Group I and only 1 microadenoma in Group II. The mean follow-up was 6.4 years, 85% (51/60) of patients in Group I, 93% of patients in Group II, and only 50% of those treated with irradiation alone achieved tumor control. With subsequent salvage treatment, overall tumor control in Group I was 97%. The mean time to recurrence was 3.7 years (Group I), 4.5 years (Group II), and 4 years (Group III). In summary, combined treatment is effective to decrease the chance of local recurrence of pituitary adenomas. Nevertheless, because of successful salvage treatment after surgical failure, overall outcome is similar. Without persistent symptom after surgery or large residual tumor in or near the critical structures, postoperative irradiation can be deferred until tumor regrowth.