Management of cystic craniopharyngiomas with stereotactic endocavitary irradiation using colloidal 186Re: a retrospective study of 48 consecutive patients.

OBJECTIVE: We retrospectively reviewed the results of stereotactic endocavitary irradiation with colloidal 186Re in the treatment of cystic craniopharyngiomas.

METHODS: Among 54 consecutive patients included in a 186Re stereotactic endocavitary irradiation procedure, 42 patients (29 male and 13 female; average age, 38.7 years) received therapeutic injection via intracystic catheter introduced under stereotactic conditions. The mean follow-up period was 43 months (range, 8-148 months). Endocavitary irradiation was the primary treatment for 15 patients and an adjuvant treatment for 27 patients. The mean volume before irradiation was 8.07 mm3, and the mean radiation dose was 381 MBq.

RESULTS: Cystic mean volume after irradiation was 2.6 cm3 (P < 0.001 with initial volume). The retraction of the cyst was complete for 17 patients (44%) and partial for 17 (44%). In partial retraction, cystic volume decreased more than 50% for 12 (3%) patients and less than 25% (13%) for 5. Cystic volume remained the same or increased for 5 (13%) patients. Concerning visual functions, 12 (44.5%) patients improved and 2 worsened, despite tumor control. No endocrinological deterioration occurred. Among 17 patients with preoperative cognitive dysfunction, 10 improved and 6 had no change. One patient showed memory alteration 4 months after stereotactic endocavitary irradiation despite cyst volume reduction. No mortality occurred.

CONCLUSION: 186Re stereotactic endocavitary irradiation for the treatment of cystic craniopharyngiomas is a safe and effective procedure with a tumor control rate greater than 70%. This treatment can be used for first-intention treatment of pure cystic craniopharyngiomas or for second-intention treatment of cystic recurrences.