RGD uses the Human Disease Ontology (DO, https://disease-ontology.org/) for disease curation across species. RGD automatically downloads each new release of the ontology on a monthly basis. Some additional terms which are required for RGD's curation purposes but are not currently covered in the official version of DO have been added. As corresponding terms are added to DO, these custom terms are retired and the DO terms substituted in existing annotations and subsequently used for curation.
This is a premalignant neoplastic process that affects the endometrial epithelium and glands. It is a neoplastic clonal expansion of endometrial glands characterized by cytologic changes of the epithelium and the presence of an increased number of endometrial glands. The glands form crowded aggregates with tubular or branching patterns which are cytologically distinct from the background architectural and cytological pattern. It is associated with molecular changes seen in endometrioid endometrial carcinoma, including microsatellite instability, PAX2 inactivation, and PTEN, KRAS, and CTNNB1 gene mutation