Immunohistochemically, the tumor showed positive for AE1/AE3, CAM5.2, estrogen receptor, progesterone receptor, desmin, WT1, calretinin (Fig. 2D), vimentin, p16, p53, inhibin (partially), and α-smooth muscle actin (partially) and negative for CD10, cyclinD1, CD117, MyoD1, myogenin, caldesmon, SF1, CD99, SOX10, and HMB45. The gene discussed is PGR; the disease is neoplasm.