Human thymus development and thymoma behavior remain elusive, in spite of many acquisitions in the field in last decades. In the present paper, we analyzed the immunohistochemical expression of D2-40 in the normal human thymus and thymoma. In both fetal and postnatal normal thymus, we found a strong expression of D2-40 in the subcapsular and cortico-medullary epithelial cells, and lack of expression in the thymus of involution. These findings support a role for podoplanin in the proliferation of some subtypes of epithelial cells of the normal thymus stroma. In thymoma, the expression of D2-40 was detected in neoplastic cells in 18 from 26 cases (69.23%). No correlation was found between D2-40 expression and histological types of thymoma, but strong correlation was noticed with tumor stage. Based on these results, it is suggested that D2-40 expression is a good predictor of invasion and can be considered as a potential target for therapy in selected cases. Read More →