A) Severe keratinocyte dysplasia (SKD) and GVHD in a patient 35 days post-transplant. The skin exhibits enlarged cells, enlarged nuclei, irregular nuclear contours, and prominent nucleoli. Keratohyaline granules are prominent. A fragmenting nucleus may be seen in the mid epidermis on the left. This skin additionally shows evidence of GVHD, with a lymphocyte (large arrow) and apoptotic cell (small arrow), and abundant lymphocytes in the dermis. B) SKD in a patient 77 days post-transplant. There is epidermal atrophy, along with the features of SKD of enlarged cells, enlarged nuclei, and prominent nucleoli.