Successful low-dose intracavitary irradiation of a Rathke's cleft cyst with colloidal rhenium-186

Symptomatic recurrence of an histologically verified intra- and suprasellar Rathke's cleft cyst (RCC) was observed 4 months following transsphenoidal microsurgery. The space-occupying cyst was treated by endocavitary irradiation with colloidal rhenium-186 via a previously implanted catheter with an attached subcutaneous reservoir. The calculated dose of 4.4 Gy was able to stop the production of cyst fluid. Follow-up after intracavitary irradiation extends over 13 months. The cyst, with an initial size of 3 x 3 x 4 cm, has been reduced to 1.1 x 1.06 x 1.2 cm. The production of cyst fluid has decreased from 25 - 30 ml within 2 months before treatment to zero. The patient's visual and mental status as well as her quality of life are normal.