CD34 and Splenomegaly: In turn, IL-6 plasma levels correlated with BM fibrosis (p = 0.0056; r = 0.49), splenomegaly (p = 0.018; r = 0.46), and the number of circulating CD34+ cells (p = 0.029; r = 0.48) and correlated negatively with hemoglobin values (p = 0.047; r = −0.39; Figures 3(a), 3(b), 3(c), and 3(d)).