[Analysis of the results of 143 cases of pituitary micro-adenoma treated by Linac X-Knife stereotactic radioneurosurgery].

BACKGROUND & OBJECTIVE: The trans-sphenoid surgery was one of the main methods for the treatment of functional pituitary micro-adenoma for many years, while the development of radiosurgical techniques in recent years has given neurosurgeons new ways to treat functional pituitary micro-adenoma. This report aimed to ascertain the effectiveness of X-Knife stereotactic radioneurosurgery on pituitary micro-adenoma.

METHODS: From June 1996 to June 2001, 143 cases of functional pituitary micro-adenoma were treated by X-Knife radiosurgery, in which 73 cases of secreting prolactin (PRL),54 cases of secreting growth hormone(GH), 13 cases of secreting adrenal corticotrophin hormone (ACTH), and 3 cases of secreting both PRL and GH. The radiosurgical procedure included local anesthesia administration, head-ring mounting, serial thin slice CT scanning with contrast enhancement, CT image transfer, treatment planning on the computer workstation, stereotactic localization of the target onto the Linac isocenter, and then the Linac was used to perform multiple non-coplannar arc radiation. All cases received single fraction radiosurgery.

RESULTS: After X-Knife radiosurgery, follow-up ranged 3-60 months (median 38.4 month). Among those 112 cases that acquired follow-up, 78(69.7%) cases showed good clinical improvements, 10(8.9%) cases showed relatively good clinical improvements, 19(16.8%) cases showed no clinical improvement, and 5(4.6%) cases had progression of disease and enlargement of the adenoma.

CONCLUSION: X-Knife radiosurgery is a safe and effective technique for the treatment of functional pituitary micro-adenoma. While for young patients, the diagnosis of pituitary micro-adenoma and use of X-Knife radiosurgery should be very cautious, otherwise hypopituitarism might be resulted.