obsolete_Thymoma Type B1 true DOID:6917 lymphocyte-rich thymoma EFO:1000584 thymoma, organoid ICDO:8583/1 thymoma type B1 MONDO:0004036 organoid thymoma Replaced by Mondo term MONDO_0006459, with which this term was previously merged. Use: http://purl.obolibrary.org/obo/MONDO_0006459 predominantly cortical thymoma http://purl.obolibrary.org/obo/MONDO_0006459 NCIT:C6887 UMLS:C1266094 lymphocyte-predominant thymoma A thymic epithelial neoplasm characterized by the presence of expanded areas which resemble the normal thymic cortex. The neoplastic epithelial cells are small and scant and there is a dense T-lymphocytic component present. Areas of medullary differentiation with or without Hassall's corpuscles are also present. It may be associated with myasthenia gravis, pure red cell aplasia, and hypogammaglobulinemia. It has a low grade malignant potential. The majority of cases occur in the anterior mediastinum as Masaoka stage I tumors. A minority of the cases occur as stage II tumors. 3.88.0