Fig. 1.

Histopathological findings of the tumor. (A) There are foci of transition from follicular variant of papillary carcinoma to mucoepidermoid carcinoma, H&E stained, ×40. (B) Papillary carcinoma cells show nuclear groove, ground glass nuclei and intranuclear psudoinclusions, H&E stained, ×400. (C) Mucoepidermoid carcinoma is solid and cystic lesion composed of columnar cells and squamous cells, H&E stained, ×40. (D) Columnar tumor cells have cilia, H&E stained, ×400. (E) Mucinous material in cystic space, mucocytes and cytoplasmic border of columnar cells are positive by PAS staining, ×200. (F) Small cysts lined with ciliated columnar cells (solid cell nests) are seen around the main tumor, H&E stained, ×200.