STAT5B and lymphoma: Intriguingly, the presence of (1) epitheliotropic pattern and angiotropism, (2) the frequent expression of CD8 and cytotoxic markers, (3) the evidence of recurrent mutation in JAK2 and STAT5b genes, (4) the involvement of epithelial interfaces, and (5) the very aggressive clinical behavior are common denominators between MEITL and aggressive epidermotropic cytotoxic T-cell lymphoma, a rare lymphoma involving the skin.