The enlightenments from ITMIG Consensus on WHO histological classification of thymoma and thymic carcinoma: refined definitions, histological criteria, and reporting

The World Health Organization (WHO) histological classification of the thymoma and thymic carcinoma (TC) has been criticized for poor interobserver reproducibility or inconsistencies in the routine pathological diagnosis. The International Thymic Malignancy Interest Group (ITMIG) panel achieved an agreement to maintain the widely accepted WHO framework but to refine historic definitions and histological criteria, and further introduce some new terms with the aim to improve interobserver reproducibility. This review addresses the enlightenments we can get from the ITMIG consensus on the WHO histological classification of the thymoma and TC, which may be helpful for most pathologists.