The most common adenoma subtype was prolactinoma (107/215, 49.8%), followed by non-functioning adenoma (77/215, 35.8%), GH-secreting adenoma (18/215, 8.4%), ACTH-secreting adenoma (8/215, 3.7%), and other/multiple types (5/215, 2.3%). This evidence concerns the gene GH1 and adenoma.