Monarch Disease Ontology entry MONDO_0016974 (thymoma type B) is an epithelial neoplasm arising from the thymus. It may be associated with myasthenia gravis, pure red cell aplasia, and hypogammaglobulinemia. It includes thymoma type B1 which is a thymoma of low grade malignant potential, thymoma type B2 which is a thymoma of moderate malignancy, and thymoma type B3 which is also known as well differentiated thymic carcinoma. Also known as: Dendritic cell thymoma, dendritic cell thymoma, dendritic cell thymoma (disease), epithelioid thymoma, plump cell thymoma, primary thymic epithelial neoplasm type B, primary thymic epithelial tumor type B, primary thymic epithelial tumour type B.