Morphologic and immunophenotypic features of patients with AML with RARG rearrangement. (A) Morphologic features of 8 cases with RARG rearrangement (top and middle) and 4 cases with PML::RARA (bottom). Most blasts had hypergranular cytoplasm (UPNs 11, 15-17, and 31 and APL-1, -2, and -4) or hypogranular cytoplasm (UPNs 10, 14, and 19 and APL-3). Auer rods were also present in some cases (UPNs 10 and 14 and APL-1 and -2). Most blasts harbored an irregular round, oval, or bilobed nucleus that was strongly suggestive of French-American-British classification type M3. (B) Comparison of immunophenotyping features between patients with RARG rearrangement (X::RARG, n = 34) and those with PML::RARA (n = 221). The expression of surface markers was not different between the 2 groups, except for CD38 (0 vs 98.5%; P < .0001) and CD117 (84.4% vs 96.7%; P = .01).