CD28 and angioimmunoblastic T-cell lymphoma: In patients with AITL, the genes with relatively high mutation frequencies were TET2 (73%), RHOA (52%), DNMT3A (42%), IDH2 (27%), STAT3 (9%), TP53 (9%), CD28 (6%), FAT1 (6%), and KMT2D (6%), NOTCH1 (6%).