“…Lichen planus-like eruptions and poikiloderma affecting the dorsal aspects of the hands, forearms, and trunk are the most typical features of early stage non-sclerotic cutaneous chronic GVHD, its histopathological hallmarks being hyperkeratosis, focal hypergranulosis, acanthosis, basal cell necrosis, vacuolar degeneration of the basal layer, and a distinctive superficial perivascular or band-like lymphoid cell infiltrate with perifollicular fibrosis ( 20 ). Sclerodermatous lesions usually develop progressively over the trunk, buttocks, hips, and thighs, with localized morphea-like features, diffuse sclerosis, or lichen sclerosus-like features, characterized by collagen homogenization of the dermis and/or subcutaneous tissues ( 17 , 20 ). In this mini-review, we will address the pathophysiology of cutaneous GVHD as addressed mostly using models of experimental allo-HSCT in mice, highlighting recent advances in the field and discussing some of the key challenges that remain.…”