Introduction: To evaluate the response to cabergoline (CBG) treatment in patients with non-functioning pituitary adenomas (NFPA).
Subjects and methods: Retrospective, single tertiary care center study. A total of 44 patients were treated with 3 mg/week of CBG, 32 after surgical treatment (transsphenoidal surgery [TSS] in 27 and TC in 5 patients) and 12 as primary therapy. Mean age was 59.2 ± 12 years and 23 (52.2%) were women. Response to therapy was ascertained by serial magnetic resonance imaging. The median duration of CBG therapy was 30 months (IQR 24-48). Response to CBG therapy was defined as a greater than 20% reduction in tumor size and volume.
Results: A significant reduction in tumor size was documented in 29 patients (66%), whereas in 11 patients (25%) the tumor increased in size and in 4 (9%), it remained stable. Significant tumor shrinkage was documented in 4 (33.3%) of 12 patients treated primarily and in 23 (71.8%) of those treated secondarily. The three-year progression-free survival was 0.61.
Conclusion: Cabergoline therapy is effective in reducing tumor growth in over two thirds of patients with NFPA, however 16% of patients will escape to this beneficial effect and will require alternative forms of treatment to halt tumor progression.
Keywords: Nonfunctioning pituitary adenomas; cabergoline; dopamine agonists; dopamine receptors.