Among the multilayered SECs, the superficial/luminal layer showed mucin 4 (MUC4), cytokeratin 5/6 (CK5/6), and CK7 expression in 5 cases (100%); MUC1, carcinoembryonic antigen (CEA), CA19-9, and thrombomodulin expression in 4 cases (80%); Wilms' tumor-1 (WT-1) and Hector Battifora mesothelial-1 (HBME-1) expression in 2 cases (40%), but it did not express p63 or D2-40.
All or nearly all epithelial cells with aberrant p63 and WT-1 expression lacked the expression of estrogen receptor and progesterone receptor, whereas they had a substantially higher proliferation index than their counterparts with p63 and WT-1 expression.