Gamma knife surgery in management of secretory pituitary adenoma preliminary evaluation of role, efficacy and safety

Historically the treatment armamentarium for secretory pituitary adenomas included neurosurgery, medical management, fractionated radiotherapy and recently gamma knife surgery (GKS), the goal of this study is to evaluate the efficacy, safety and role of gamma knife surgery for treatment of secretory pituitary adenomas regarding hormonal and adenoma size control, between mid of 2005 and 2012 a retrospective analysis of 54 consecutive patients with secretory pituitary adenomas underwent GKS at the International Medical Center (IMC) Cairo-Egypt, 10 patients with adrenocorticotrophic hormone secreting adenoma, 24 prolactin secreting adenoma and 20 with growth hormone secreting adenoma, in 25 patients GKS was the secondary to a prior surgery with failure of hormonal control even in addition of medical treatment, in the other 29 the secretory pituitary adenomas not controlled with medical treatment alone, the median follow up period was 28 months(12-84 months), achieving hormonal control was either normalization or marked decline of abnormal hormone level >50%, radiological tumour size control was either tumour size stabilization or reduction, among the 54 patients 31 had microadenoma of 1cc volume or less, over all 34 patients (63%) had hormonal control and 51 patients (94%) had tumor size control after GKS, there was a direct correlation between tumor size, prescription radiation dose and post-gamma knife hormonal and size control, 29 out of the treated 31 microadenomas cases showed both hormonal and size control, inconclusions gamma knife surgery is safe and effective treatment for secretory pituitary adenomas failed to respond to medical treatment alone or with postsurgical residual or recurrence especially microadenomas.