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.
A squamous cell carcinoma that has a solid, closely packed growth of cells with hyperchromatic nuclei, scant cytoplasm, small cystic spaces, and foci of necrosis. It has overlying squamous dysplasia, rare foci of overt keratinization, and/or coexistent keratinizing squamous cell carcinoma. (DO)