In current concepts, the primary EMPD immunophenotype usually shows cytokeratin 7 (CK7)+/ cytokeratin 20 (CK20)-/ gross cystic disease fluid protein-15 (GCDFP-15)+ while the secondary EMPD shows CK7+/CK20+/GCDFP-15- [13–15]. This evidence concerns the gene KRT20 and extramammary Paget disease.