Figure 1
From: Interobserver reproducibility in the diagnosis of flat epithelial atypia of the breast
Columnar cell change. (a) Low power shows a terminal duct lobular unit with dilated acini. (b) At high power, these acini are lined by a single layer of columnar cells with nuclei that are ovoid, rather than rounded, in shape. Nucleoli are inconspicuous or absent. The cells are oriented perpendicular to the basement membrane in a ‘picket fence’ arrangement.
