The World Health Organization (WHO) classification of tumors is a continually evolving system that reflects the latest understanding of how tumors behave, both biologically and clinically. In the 2021 update for the classification of thymic epithelial tumors, refinements were made to better categorize these complex tumors based on morphology, genetics, and clinical outcomes. Thymomas, originating from the epithelial cells of the thymus, are particularly nuanced given their variable clinical presentation and associations with autoimmune diseases such as myasthenia gravis.