PHF6 and acute lymphoblastic leukemia: While sample sizes are small, patients with T-ALL harboring PHF6 mutations tend to be older, have been demonstrated to have lower white blood cell counts than other T-ALL patients, as well as lower hemoglobin and platelet levels, splenomegaly/lymphadenopathy, and have blasts with a tendency to express CD13 (26, 29, 37).