SAT623 Everolimus For Treatment-refractory Prolactinomas

Disclosure: A.L. Lin: Grant Recipient; Self; Bristol-Myers Squibb. E.B. Geer: None. G. Page-Wilson: None. R.S. Magge: None. R.J. Young: Consulting Fee; Self; Olea Sphere, ICON plc. V. Tabar: None. Introduction: Treatment-refractory prolactinomas are life-limiting tumors without a standard of care treatment option after the oral alkylator, temozolomide, fails to provide tumor control. Methods: We reviewed an institutional database of pituitary tumors for patients with aggressive prolactinomas who progressed following treatment with a dopamine agonist, radiotherapy and temozolomide. In this cohort of patients with aggressive prolactinomas, we identified 4 patients who were treated with everolimus and we report their response to this therapy. Treatment response was determined by a neuroradiologist, who manually performed volumetric assessment and determined treatment response by Response Assessments in Neuro-Oncology (RANO) criteria. Results: 3 of 4 patients who were treated with everolimus had a biochemical response to therapy and all patients derived a clinically meaningful benefit based upon suppression of tumor growth. While the best overall response as assessed by RANO criteria was stable disease for the 4 patients, a minor regression in tumor size was appreciated in 2 of the 4 patients. Conclusion: Everolimus is an active agent in the treatment of prolactinomas that warrants further investigation. Presentation: Saturday, June 17, 2023