MUC5AC and mucoepidermoid carcinoma: In this case, the positive immunohistochemistry staining for CK7 and p63 and the negative staining for PAS, PASD, mucin, and S100 and mammaglobin helped rule out other neoplasms such as mucoepidermoid carcinoma, and epithelial myoepithelial carcinoma, metastatic renal clear-cell carcinoma, clear-cell myoepithelial carcinoma, and other mammary-type tumors.