Univariate analysis showed that red blood cell (RBC) transfusion dependence (HR 9.02, 95% CI 4.0–20.35), platelet transfusion dependence (HR 8.17, 95%CI 3.83–17.37), 100% donor chimerism in CD33 + cells (HR 0.21, 95%CI 0.07–0.62), unfavorable molecular status (HR 4.41, 95%CI 1.87–10.39), normal spleen size (HR 0.42, 95%CI 0.19–0.94), grade ≥ 2 bone marrow fibrosis (vs. grade ≤ 1; HR 2.7, 95%CI 1.1–6.93) and poor graft function (HR 2.6, 95%CI 1.22–5.53) at day +100 were statistically significantly associated with relapse-free survival (RFS). Here, CD33 is linked to primary myelofibrosis.