High-grade PIN : Keratin 34bE12
Immunostaining with HMWCK shows the entire spectrum of changes in the basal cell layer in this image. The benign glands on the upper right show intact basal cell layer. The larger glands in the middle are high-grade PIN with fragmented basal cell layer. The smaller glands on the left are adenocarcinoma and they are completely devoid of basal cells.