Differential diagnosis between ALCL and cHL can be made by expression of cytotoxic molecules such as Granzyme B, Perforin and T-cell-restricted intracellular antigen-1 (TIA1), EMA and CD45/LCA which are typical of ALCL, while positivity for CD15 (in 70% of cases), PAX5 (90%) and LMP1 (in 50%) are typical of cHL. The gene discussed is PAX5; the disease is classic Hodgkin lymphoma.