The tumor-suppressive role of A20 is particularly evident in lymphomas, where somatic mutations are observed in up to 30% of patients with B-cell lymphomas, such as Hodgkin’s and non-Hodgkin lymphomas and mucosa-associated tissue (MALT) lymphoma [49,50,51]. The gene discussed is TNFAIP3; the disease is B-cell non-Hodgkin lymphoma.