BCR::ABL1 levels at first month after TKI discontinuation predict subsequent maintenance of treatment-free remission: A study from the "GRUPPO TRIVENETO LMC".

We analyzed BCR::ABL1 expression at stop and in the first month after discontinuation in 168 chronic myeloid leukemia patients who stopped imatinib or 2nd generation tyrosine kinase inhibitors (2G-TKIs) while in sustained deep molecular response. Patients were divided among those who maintained response (group 1, n = 123) and those who lost major molecular response (group 2, n = 45). Mean BCR::ABL1 RNA levels 1 month after discontinuation were higher in group 2 than in group 1 (p = 0.0005) and the difference was more evident 2 months after stop (p < 0.0001). The same trend was found both for imatinib and 2G-TKIs. A receiver operating characteristic (ROC) analysis to determine a threshold value of BCR::ABL1 at 1 month after discontinuation identified a cut-off value of 0.0051%, with 92.2% specificity, 31.7% sensitivity and a likelihood ratio of 4.087.

BCL-2 Expression in AML Patients over 65 Years: Impact on Outcomes across Different Therapeutic Strategies.

BCL-2 overexpression has been associated with resistance to chemotherapy and reduced survival in acute myeloid leukemia (AML), but few data are available in elderly patients, a subset accounting for majority of AML cases and with dismal prognosis. We retrospectively analyzed 113 AML patients aged ≥65 years treated with 3 + 7 chemotherapy (n = 51) or hypomethylating agents (HMAs) (n = 62), evaluating the role of BCL-2 expression on complete remission (CR) and overall survival (OS). BCL-2 was expressed in 81 patients (72%), more frequently in those with unfavorable cytogenetic-molecular risk. CR was achieved in 34.5% cases, without differences according to BCL-2 expression or induction therapy. In the whole population 1-year OS was 39%, similar in BCL-2+ and BCL-2- cases. In BCL-2 positive patients OS was superior with HMAs (56% vs. 25% with 3 + 7; p = 0.02), while no advantage for HMA was found in BCL-2 negative cases (36% vs. 27% for 3 + 7). Therapy with HMAs was the only factor associated with longer OS in BCL-2+ AML by multivariable analysis. Use of HMAs, possibly in combination with BCL-2 inhibitors, appears to be particularly appealing in BCL2+ AML, where it is associated with superior survival.

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 two 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. We aimed to elucidate the prognostic role of CD200/BCL2 co-expression and its association with specific leukemia subsets. Materials and Methods: We analyzed 242 adult AML patients uniformly treated with intensive chemotherapy, evaluating the impact of CD200 and BCL2 expression on complete remission (CR), disease-free survival, 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%) displaying double negativity (DN), and 92 patients expressing only either CD200 (n=47) or BCL2 (n=45). CR was achieved in 71% of cases, being less frequent 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%) or DN cases (60%; p=0.004). Other factors associated with worse OS were advanced age, CD34 positivity, secondary AML, and high white blood cell count at diagnosis; combining these 4 factors with CD200/BCL2 DP, we identified 6 groups with significantly different rates of 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 and resulting in worse prognosis.

ABCG2 and CD200 define patients at high risk of relapse in ELN favorable subgroup of AML.

OBJECTIVE: Overexpression of ABCG2 and CD200 has been independently associated with poor outcome in acute myeloid leukemia (AML). However, no data are available on the role of these two factors in patients with core-binding factor (CBF)-positive or FLT3-negative/NPM1-mutated cytogenetically normal (CN) AML. METHODS: We analyzed 65 adult AML patients with CBF+ (n=16) or FLT3-/NPM1+ CN (n=49), evaluating clinical and biological factors associated with complete remission attainment, leukemia-free survival (LFS) and overall survival (OS). RESULTS: ABCG2 was expressed in 36 (55%) cases, and CD200 was positive in 33 (51%) cases, six at high levels. Both ABCG2 and CD200 positivity have a negative impact on relapse risk: 3-year LFS was 51% vs 82% in ABCG2+ cases (RR 3.3), 49% vs 82% in CD200+ patients (RR=4.4), and 25% in CD200- high cases (RR=17.1). ABCG2 and CD200 affected also OS with 3-year OS of 39% in ABCG2+ (compared to 71% in ABCG2-; RR=2.6) and CD200+ (compared to 68% in CD200-; RR=2.5) patients. CONCLUSIONS: Our data confirm a negative impact of ABCG2 and CD200 overexpression also in AML patients considered at favorable risk according to ELN cytogenetic/molecular classification.