Role of gamma knife radiosurgery in the management of pituitary adenomas and craniopharyngiomas

Abstract

Introduction: Radical microsurgical removal of pituitary adenomas (PAs) and craniopharyngiomas (CPHs) is often difficult. In such cases radiosurgery can be used as a second-line treatment option.

Materials and methods: Our series included 436 PAs and 164 CPHs. The majority of patients had large or giant tumors and were treated with microsurgery. Additionally, between June 2008 and August 2011, a total of 29 PAs and 10 CPHs underwent radiosurgery using Leksell Gamma Knife PerfeXion. At the time of treatment the volume of the PAs varied from 0.6 to 26.0 cm3 (mean 5.9 cm3) and that of the CPHs from 0.19 to 17.0 cm3 (mean 6.6 cm3). The marginal doses ranged from 12 to 15 Gy (mean 14.5 Gy) for nonsecreting PAs, from 22 to 25 Gy (mean 24 Gy) for hormone-secreting PAs, and from 8 to 14 Gy (mean 11 Gy) for CPHs.

Results: The postoperative mortality rates after surgical removal of PAs via the transspenoidal approach and craniotomy were 2.4 % and 8.0 %, respectively, whereas after surgery for CPH it was 5.9 %. No major complications were noted in our limited number of patients after radiosurgical treatment. Taking into consideration only cases with radiological follow-up of at least 12 months, shrinkage of the tumor was demonstrated in 5 of 11 patients with a PA and in 4 out of 6 patients with a CPH.

Conclusion: Radiosurgery is safe and effective second-line management option in cases of recurrent or residual PA or CPH. Occasionally, it can be applied even as a primary treatment in selected patients.