Sarcomatoid PCa has a biphasic character, markedby a squamous component with sarcomatous differentiation of spindlecells.14 This epitheliomesenchymal transitionis characterized by decreased expression of E-cadherin and increasedexpression of N-cadherin, which is responsible for the mobile phenotypeof the cells.14 Cadherins are polypeptidesresponsible for epithelial intercellular adhesion, associated witha group of catenin proteins that bind the actinic microfilaments ofthe cytoskeleton.71 The gene discussed is CDH17; the disease is posterior cortical atrophy.