NPM1 and anaplastic large cell lymphoma: Immunohistochemistry showed that these lymphoid cells expressed CD30 (a hallmark feature of ALCL) (Figure 2B), ALK in a nuclear and cytoplasmic pattern (suggesting that the translocation partner responsible for ALK overexpression is nucleophosmin [NPM1]) (Figure 2C), EMA (epithelial membrane antigen, almost always positive in ALK+ ALCL) (Figure 2D), and Granzyme B (partially, supporting the active cytotoxic phenotype of the tumor cells) (Figure 2E).