Transsphenoidal neurosurgery is the gold standard treatment for pituitary adenomas; however, it can be contra-indicated or ineffective. In these cases, medical treatment based on somatostatin analogs or GH receptor antagonist, can be used. Another approach is to use radiation therapy.
Stereotactic radiosurgery (SR) is a procedure aiming at controlling hormone hypersecretion and tumor size of pituitary adenomas. This talk will mainly deal with the long-term efficacy and adverse effects of Gamma knife, a modality of stereotactic radiosurgery, in secreting and non-secreting pituitary adenomas. Recent long-term data confirm the anti-secretory efficacy of the procedure (about 50% remission in hypersecreting tumors) but also a previously unknown low risk of recurrence (about 210% cases), in contrast with conventional radiotherapy. The main drawback is the time to remission estimated to range from 12 to 60 months. The anti-tumoral efficacy is observed in about 90% cases. Hypopituitarism is the main side-effect, observed in 2040% cases. Comparison with conventional radiotherapy reveals a lower rate of remission counterbalanced by a more rapid efficacy, and a lower rate of hypopituitarism for radiosurgery. Recent short-term results about stereotactic fractionated radiotherapy suggest a risk of hypopituitarism similar to the one observed with radiosurgery. SR is thus probably still useful in the therapeutic algorithms of pituitary adenomas, despite the fact that antisecretory drugs, particularly for acromegaly, are becoming more and more effective and well tolerated.
Castinetti et al. Nat Rev Endocrinol 2010 6(4) 21423.
Castinetti et al. JCEM 2009 94(9) 340007.