Crowding of acini, nuclear enlargement, and the presence of scant cytoplasm imparts a basophilic appearance to post-atrophic hyperplasia. In contrast, foci of adenocarcinoma typically show abundant pale pink or amphophilic cytoplasm. In challenging cases, the immunostain for high molecular weight cytokeratin is invaluable (see next image). Post-atrophic hyperplasia: A histologic mimic of adenocarcinoma. Am J Surg Pathol 19(9): 1068-1076, 1995 .