An early study using anti-CTLA4 antibody, ipilimumab, as a single agent in patients with hematologic malignancies who relapsed after allogeneic SCT, demonstrated modest efficacy in myeloid diseases, including 4 durable CR in patients with extramedullary disease relapse among 12 patients with AML [86]. The gene discussed is CTLA4; the disease is acute myeloid leukemia.