Monarch Disease Ontology identifier MONDO_0003493 (thymus squamous cell carcinoma) is a rare primary thymic carcinoma, characterized by the presence of keratinizing or non-keratinizing malignant squamous cells. Approximately 10-20% of cases occur in combination with thymoma. The prognosis depends on the tumor stage and the degree of cellular differentiation. Also known as: Thymus squamous cell carcinoma, epidermoid thymic carcinoma, squamous cell carcinoma of Thymus, squamous cell carcinoma of the Thymus, thymic squamous cell carcinoma.