CHL, PMBL, EBV+ DLBCL, and ALCL share common features, such as CD30 positivity, PD-L1 and/or PD-L2 expression, chromosome 9p24.1 alterations, JAK/STAT activation, and EBV infection (Table 1; Figure 1). The gene discussed is PDCD1LG2; the disease is Epstein-Barr virus infection.