Conclusion: TT-UMP demonstrated very heterogeneous immunohistochemical profiles. WDTs-UMP revealed a certain tendency toward a PTC profile, suggesting a possible pathogenetic link between these two entities. However, immunohistochemistry is to be regarded more as a supporting factor, while morphological criteria should always prime in the diagnostic decision. Results: There was a positive correlation between TPCFV and HMWCK, CK 19, HBME1, Galectin 3, Fibronectin (p< 0.05), but there was no correlation with TPCFV and RET/ PTC (p>0.05). HBME-1 and CK 19 stained strong and diffuse positive in TPCFVs but weak and focal in FAs.