MON-019 Gamma Knife Radiosurgery For The Management Of Pituitary Adenomas In Tertiary Care Hospital In Mexico City

Abstract Disclosure: R. Del Valle Robles: None. G. Gonzalez: None. D. Porras Farret: None. Pituitary adenomas represent a significant clinical concern due to their potential impact on hormonal function and quality of life. Current treatment options are varied, with Gamma Knife radiosurgery gaining increasing relevance. However, rigorous evaluation of its safety and efficacy in managing pituitary adenomas remains essential to optimize available therapies. This study aimed to evaluate our center's experience using Gamma Knife radiosurgery for the management and size reduction of pituitary adenomas. We conducted an observational, descriptive, longitudinal, and retrospective study. Patients with pituitary adenomas treated with Gamma Knife at our hospital were included. Eligibility criteria encompassed specific demographic characteristics and prior treatment history. A total of 274 patients were included, with a mean age of 45.9 ± 14.5 years; 135 (49.3%) were women and 139 (50.7%) men. Regarding tumor size, 151 (55.1%) were macroadenomas, 89 (32.5%) microadenomas, and in 35 (12.4%) tumor size was unspecified. The most frequent hormonal pattern was non-functioning (57.7%), followed by prolactin-secreting (15.7%) and growth hormone-secreting (15%) adenomas. Prior surgery was reported in 193 cases (70.4%), including transsphenoidal surgery (87%), craniotomy (11.9%), and radiosurgery (0.7%). Pre-treatment tumor volume was reported in 225 cases with a median of 1.30 (0.56-3.08) cm³, and post-treatment in 106 cases with a median of 0.91 (0.27-2.11) cm³. In 104 patients with both measurements available, median volumes were 2.05 (0.71-3.61) and 0.91 (0.26-2.06) cm³, respectively, showing a significant reduction (P<0.001). Tumor control rates were 50% for ACTH-secreting adenomas, 88.9% for GH-secreting, 58.8% for prolactinomas, and 100% for mixed-secreting adenomas. The greatest volume reductions were observed in patients with macroadenomas, mixed or non-functioning tumors, and those without prior surgery. These findings suggest that larger tumor volume may be associated with greater benefit. In conclusion, our results demonstrate tumor control rates comparable to those reported in the literature. Gamma Knife radiosurgery appears to be an effective treatment option and may be a valuable alternative prior to surgical intervention for volume control in pituitary adenomas. Presentation: Monday, July 14, 2025