RESUMEN
Seventy four patients with pituitary adenoma received radiation therapy(RT) on the pituitary area using 6 MV linear accelerator during the past 7 years at the Division of Radiation Therapy, kangnam St. mary's hospital, Catholic University Medical College. Thirty nine were men and 35 were women. The age ranged from 7 to 65 years with the mean being 37 years. Sixty five (88%) patients were treated postoperatively and 9(12%) primary RT. To evaluate the effects of RT, we analyzed the series of endocrinologic studies with prolactin(PRL), growth hormone(GH), adrenocortiotrophic hormone (ACTH), leuteinizing hormone (LH), follicular stimulating hormone(FSH) and thyroid stimulating hormone(TSH) etc after RT. All but one with Nelson's syndrome showed abnormal neuroradiologic changes in the sella turica with invasive tumor mass around supra-and/or parasella area. The patients were classified as 23(29%) prolactinomas and 20 (26%) growth hormone (GH) secreting tumors, and 6(8%) ACTH secreting ones consisting of 4 Cushing's disease and 2 Nelson's syndrome. Twentynine(37%) had nonfunctioning tumor and four (5%) of those secreting pituitary tumors were mixed PRL-GH secreting tumors. The hormonal level in 15(65%) of 23 PRL and 3(15%) of 20 GH secreting tumors returned to normal by 2 to 3 years after RT, but five PRL and five GH secreting tumors showed high hormonal level requiring bromocriptine medication. Endocrinologic insufficiency developed by 3 years after RT in 5 of 7 panhypopituitarisms, 4 of seven hypothyroidisms and one of two hypogonadisms, respectively, Fifteen(20%) patients were lost to follow up atter RT.