Relationship between expression of cancer-related proteins and tumor invasiveness in thymoma.

Distinction between non-invasive and invasive thymomas is almost impossible by histologic examination alone, because the morphology of invasive thymoma does not significantly differ from that of non-invasive thymoma [1,2]. However, tumor invasiveness is regarded as the most important factor affecting survival in thymoma [3]. In the present study, we examined the expression of some cancer-related proteins in thymoma by immunohistochemistry to determine whether the expression of these proteins is different between non-invasive and invasive thymomas.