Impact of Concomitant Aberrant CD200 and BCL2 Overexpression on Outcome of Acute Myeloid Leukemia: a Cohort Study From a Single Center.

Objective CD200 and BCL2 overexpression is, independently, associated with inferior survival in acute myeloid leukemia (AML), and these 2 factors are frequently co-expressed; however, no data are available on the role of concomitant aberrant CD200 and BCL2 expression on outcome of AML patients. Material and Methods We analyzed 242 adult AML patients uniformly treated with intensive chemotherapy, evaluating the role of CD200 and BCL2 expression on complete remission (CR), disease-free survival (DFS) and overall survival (OS). Results CD200 and BCL2 were expressed in 139 (57.4%) and 137 (56.6%) cases, respectively, with 92 patients (38%) displaying double positivity (DP), 58 (24%) double negativity (DN) and 92 patients expressing only either CD200 (47) or BCL2 (45). CR was achieved in 71% of patients, being lower in DP patients (60%) compared to other groups (76-81%, p<0.001). In the whole population 3-year OS was 44%, being lower in DP patients (28%) than in patients with single CD200 or BCL2 expression (47%) than in DN cases (60%; p=0.004). Other factors associated with worse OS were advanced age, CD34 positivity, secondary AML and high WBC at diagnosis; combining these 4 factors with CD200/BCL2 DP we identified 6 groups with significantly different survival (3-year OS ranging from 90 to 0%). Conclusion Our data support a synergistic effect of CD200 and BCL2 in AML cells, conferring an enhanced survival capacity in a permissive microenvironment, resulting in a worse prognosis.