MYD88 and lymphoma: Mutations in CD79B reported to occur in 23% of IgM gammopathy–positive DLBCL [10], were found in 20% of lymphomas with IgM gammopathy and in 13% of lymphomas without IgM gammopathy, with 13% and 7% of the lymphomas harboring both a CD79B and a MYD88 mutation.