Role of Cyber knife Radiosurgery in pituitary mass and improvement in growth hormone levels

Pituitary adenoma is one of the most common benign tumors of central nervous system, 1,2 accounting 10% of intracranial tumors.3,4 An estimated prevalence of asymptomatic small pituitary tumor is 16.7% (14.4% in autopsy and 22.5% in radiologic studies).3,4 Pituitary adenoma prevalence is based on recent crosssectional study is estimated to be 80-90 per 100,000. 30% of pituitary tumors are non-secretary and 70% secrets greater amount of pituitary hormones. In secretary adenomas 60% prolactinomas, 20% growth hormone secreting tumors and with decreasing frequency is adrenocorticotrophic hormone (ACTH) secreting tumors and thyroid stimulating hormone (TSH)) secreting tumors (10). Pituitary adenoma can be micro or macroadenoma by cutoff size of 10mm. Tumors exceeding 30-40mm are giant adenoma. Most tumors are benign, but 20-55% shows invasion.5,6