P-32 INTRACAVITARY IRRADIATION OF CYSTIC CRANIOPHARYNGIOMAS - CURRENTTECHNIQUE AND LONG-TERM RESULTS

Purpose: The management of patients with craniopharyngiomas is often m ultifaceted and multidisciplinary. The purpose of this study was to ex amine the results of phosphorus-32 intracavitary irradiation in the tr eatment of patients with predominately cystic craniopharyngiomas. Meth ods and Materials: Thirty patients with cystic craniopharyngiomas unde rwent phosphorus-32 intracavitary irradiation at our center between 19 81 and 1993. The median patient age was 26 years (range, 3-70 years). Thirteen patients had intracavitary irradiation as the primary surgery for their cystic tumors, whereas 17 patients had adjuvant intracavita ry irradiation after microsurgical resection, fractionated radiotherap y, or both. Patients in the adjuvant treatment group were more likely to have preoperative anterior pituitary insuffiency (p = 0.008 Fischer exact test) and diabetes insipidus (p = 0.003 Fischer exact test). Th e median follow-up was 37 months (mean, 46 months, range, 7-116 months ). Results: Phosphorus-32 intracavitary irradiation resulted in cyst r egression in 28 of 32 treated cysts (88%). Ten patients (33%) have had tumor progression requiring further surgical intervention. Three pati ents (10%) died: two of tumor progression, and one of unrelated causes . Visual acuity and fields improved or remained stable in 63% of the p atients. Fifteen patients had residual anterior pituitary function bef ore intracavitary irradiation and 10 (67%) retained their preoperative endocrine status. New-onset diabetes insipidus occurred in 3 of 17 pa tients (18%) who had normal posterior pituitary function preoperativel y. Fourteen of 20 adult patients (70%) continued to perform at their p reoperative functional level; 3 of 5 pediatric patients who were age a ppropriate at the time of treatment continued to develop normally. No difference was noted between primary and adjuvant treatment patients w ith respect to cyst control, visual deterioration, or endocrine preser vation after phosphorus-32 intracavitary irradiation. Conclusion: The goals of craniopharyngioma management should be tumor control with pre servation of visual, endocrine, and cognitive function. Phosphorus-32 intracavitary irradiation is an important option that enhances the lik elihood of achieving these goals in patients with primarily cystic cra niopharyngiomas.