KRT7 and neoplasm: To better characterize the cell nature, differentiation, and protein expression of this tumor, we performed an extended immunohistochemistry panel for CK7 (cytokeratin-7-7), EMA (epithelial membrane antigen), GCDFP-15 (gross cystic disease fluid protein-15), α-SMA (alpha- smooth muscle actin), S-100, p63, and CD10 immunomarkers (Novocastra Laboratories; Leica Microsystems).