Objective: The general objective of this study is to map the current knowledge in DNA methylation in Pituitary Adenomas. This regarding genetic and epigenetic findings and the translation into a clinical setting. Introduction: Pituitary tumorigenesis is currently under major investigation. The current research has turned to epigenomic analysis, investigating whether several epigenetic components like DNA methylation and histone modification can be used as markers for tumorigenesis. Several studies report genes involved in relation to hypo/hypermethylated sites. Others describe differential methylated probes/regions (DMR or DMP) and show subclassification traits. Furthermore, most recent studies aims to cluster samples based on full methylome data (unsupervised cluster analysis), while others chose to assess the most different probes (example 2000 probes) and perform the same data-analysis. Inclusion criteria: We will include all primary studies on pituitary adenomas analyzed by DNA methylation in this review. No review studies are included. They need to be regarding DNA methylation in pituitary adenomas in humans. All papers describing DNA methylation in pituitary adenomas will be included, with all languages included, but both title and abstract needs to be written in English. Methods: Relevant papers will be identified through these bibliographic databases: Medline, Embase, Cochrane Library and Scopus. Two reviewers will screen all papers based on title and abstract. All relevant papers will be included for further assessment by the same two reviewers. Full texts from each selected paper will be read, and if relevant regarding eligibility criterias, this paper will be included in the review. Disputes between these reviewers, the paper/papers will be discussed in the entire research-group.

The authors have declared no competing interest.

This study did not receive any funding

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Yes

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Yes

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Yes

All data produced in the present study are available upon reasonable request to the corresponding author