Thymic epithelial tumors include thymoma and thymic carcinoma. Histologic findings and extent of disease are key determinants of prognosis and help guide postoperative management in patients with thymic epithelial tumors. Given the relative rarity of these tumors, the use of tumor guidelines and checklists can facilitate accurate and comprehensive pathologic reporting in this setting. Diagnostic nomenclature (World Health Organization, Suster-Moran classifications) and staging criteria (modified Masaoka system) are emphasized.