Thymomas are tumors of thymic epithelial cell origin. The types of thymomas are: Type A thymoma, including atypical variantType AB thymomaType B1 thymomaType B2 thymomaType B3 thymomaMicronodular thymoma with lymphoid stromaMetaplastic thymomaMicroscopic thymomaSclerosing thymomaLipofibroadenoma Useful immunohistochemistry includes: AE1/AE3 (pan-keratins), CK19, CK20,…