Prognostic significance of CD20 expression in childhood B-cell precursor acute lymphoblastic leukemia

CD20 expression is associated with inferior survival in adults with acute lymphoblastic leukemia (ALL). We analyzed the prognostic impact of CD20 expression in 353 children with B-cell precursor ALL treated in 3 consecutive St Jude Total Therapy studies. CD20 expression (> 20%) was found in 169 patients (48%) and was more frequent in patients between 1 and 10 years of age than in those younger than 1 or older than 10 years (P = .001). None of 14 patients with MLL-AF4 expressed CD20. There was no association between CD20 expression and E2A-PBX, TEL-AML1, ploidy, white blood cell count at diagnosis, or sex. In contrast to the experience in adult ALL, our patients with CD20 expression tended to have a better treatment outcome than those without the expression: 5-year event-free survival 84% +/- 2.9% versus 78% +/- 3.1% (P = .08). These data suggest that CD20 expression is not associated with inferior outcome in pediatric patients treated with contemporary regimens.     

Adverse prognostic significance of CD20 expression in adults with Philadelphia chromosome-negative B-cell precursor acute lymphoblastic leukemia

The prognostic significance of CD20 expression in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) has been mostly studied in children and yielded conflicting results. In 143 adults with Philadelphia chromosome-negative BCP-ALL treated in the multicentric GRAALL 2003 trial, CD20 positivity over 20% was observed in 32% of patients. While not influencing complete remission achievement, CD20 expression was associated with a higher cumulative incidence of relapse (CIR) at 42 months (P=0.04), independently of the ALL high-risk subset (P=0.025). Notably, the negative impact of CD20 expression on CIR was only observed in patients with a white blood cell count (WBC) over 30×10⁹/L (P=0.006), while not in those with a lower WBC. In the former subgroup, this impact translated into lower event-free survival (15% vs. 59% at 42 months, P=0.003). CD20 expression thus appears to be associated with a worse outcome, which reinforces the interest of evaluating rituximab combined to chemotherapy in CD20-positive adult BCP-ALL. ClinicalTrials.gov ID, {"type":"clinical-trial","attrs":{"text":"NCT00222027","term_id":"NCT00222027"}}NCT00222027.     

Rituximab plus chemotherapy in children with relapsed or refractory CD20-positive B-cell precursor acute lymphoblastic leukemia

We treated three children with relapsed or refractory CD20 positive B-cell precursor acute lymphoblastic leukemia with rituximab in combination with chemotherapy, which produced a decreasing or persistent low positive minimal residual disease load. Two children subsequently underwent allogeneic stem cell transplantation and remain in complete remission at days +399 and +332.     

Potential use of CD40 ligand for immunotherapy of childhood B-cell precursor acute lymphoblastic leukaemia

Around 20% of children affected by B-cell precursor acute lymphoblastic leukaemia (BCP-ALL) still experience a recurrence of the disease after diagnosis, despite a significant improvement in the cure rate (80%). Moreover, standard therapies have high and often unacceptable acute and chronic organ toxicity, with an increased risk for secondary malignancies. Therefore, new strategies are needed to improve overall survival and decrease treatment-associated morbidity. Recent in-vitro and in-vivo studies have demonstrated that CD40 engagement improves tumour immunogenicity and, consequently, generates a strong antitumour immune response. The CD40-CD40 ligand (CD40L) system is of pivotal importance in the immune response via interactions between T cells and antigen-presenting cells. The general aim of this chapter is to review the feasibility of developing cellular strategies to increase childhood BCP-ALL immunogenicity, and the potential use of CD40L as a new strategy to induce an antileukaemia immune response in BCP-ALL.     

CD20 expression in B-cell precursor acute lymphoblastic leukemia is common in Mexican patients and lacks a prognostic value

Abstract

Classification of acute lymphoblastic leukemia (ALL) by flow cytometric immunophenotyping characterizes the disease and delineates potential therapeutic intervention. We retrospectively analyzed CD20 expression in 143 patients with newly diagnosed precursor B-cell ALL. CD20 was observed in 61% of patients at diagnosis. There was no correlation between CD20 expression and age, white blood cell count, or cytogenetic abnormalities. Despite the fact that CD20-positive ALL patients had a tendency toward a worse outcome, there was no significant difference between patients with and without CD20 expression in 3-year overall survival 65 vs. 82% (P = 0.14), and cumulative incidence of relapse 36 vs. 18% (P = 0.3) in pediatric patients and 51 vs. 53% (P = 0.31) and 35 vs. 38% (P = 0.6) in adults, respectively. In conclusion, CD20 expression appears to be more common in Mexican patients with newly diagnosed precursor B-cell ALL higher than in Caucasian populations and lacks prognostic value.     

CD20 expression in B-cell precursor acute lymphoblastic leukemia is common in Mexican patients and lacks a prognostic value

Classification of acute lymphoblastic leukemia (ALL) by flow cytometric immunophenotyping characterizes the disease and delineates potential therapeutic intervention. We retrospectively analyzed CD20 expression in 143 patients with newly diagnosed precursor B-cell ALL. CD20 was observed in 61% of patients at diagnosis. There was no correlation between CD20 expression and age, white blood cell count, or cytogenetic abnormalities. Despite the fact that CD20-positive ALL patients had a tendency toward a worse outcome, there was no significant difference between patients with and without CD20 expression in 3-year overall survival 65 vs. 82% (P = 0.14), and cumulative incidence of relapse 36 vs. 18% (P = 0.3) in pediatric patients and 51 vs. 53% (P = 0.31) and 35 vs. 38% (P = 0.6) in adults, respectively. In conclusion, CD20 expression appears to be more common in Mexican patients with newly diagnosed precursor B-cell ALL higher than in Caucasian populations and lacks prognostic value.     

Prognostic significance of CD20 expression in adults with de novo precursor B-lineage acute lymphoblastic leukemia

Immunophenotypic classification of acute lymphoblastic leukemia (ALL) has well-recognized prognostic implications. The significance of CD20 expression has been evaluated in childhood precursor B-lineage ALL with conflicting results. We retrospectively analyzed the influence of CD20 expression on outcome in 253 adults with de novo precursor B-lineage ALL treated with either conventional (VAD/CVAD) or intensive (hyper-CVAD) frontline chemotherapy regimens in the pre-rituximab era. Overall, CD20 positivity of at least 20% was associated with lower 3-year rates of complete remission duration (CRD; 20% vs 55%, P < .001) and overall survival (OS; 27% vs 40%, p = .03). In the CD20 negative subset, the 3-year rates for CRD (58% vs 42%, p = .04) and OS (60% vs 28%, P < .001) were superior for hyper-CVAD compared with VAD/CVAD; rates were particularly favorable for the CD20 negative younger age group (68% and 85%, respectively). In contrast, 3-year CRD and OS rates were uniformly poor for the CD20-positive group regardless of therapy (27% or less). Multivariate analysis for event-free survival identified older age, leukocyte count higher than 30 x 10(9)/L, presence of Philadelphia chromosome, high systemic risk classification, and CD20 positivity as independent predictors of worse outcome. In conclusion, CD20 expression in de novo adult precursor B-lineage ALL appears to be associated with a poor prognosis. Incorporation of monoclonal antibodies directed against CD20 into frontline chemotherapy regimens warrants investigation.     

IGH@ translocations co-exist with other primary rearrangements in B-cell precursor acute lymphoblastic leukemia

Primary established genetic abnormalities in B-cell precursor acute lymphoblastic leukemia include high hyperdiploidy (51–65 chromosomes), the translocations t(12;21)(p13;q22)/ETV6-RUNX1 fusion and t(9;22)(q34;q11)/BCR-ABL1 fusion, MLL rearrangements and intrachromosomal amplification of chromosome 21. These rearrangements are of prognostic and therapeutic relevance and are usually mutually exclusive. We identified 28 patients at diagnosis with both a primary genetic rearrangement and an immunoglobulin heavy chain locus translocation using chromosomal analysis and fluorescence in situ hybridization. Among these patients, the immunoglobulin heavy chain locus translocation partner gene was identified in six (CRLF2, CEBPA, CEBPB, TRA/D@, IGF2BP1 and IGK@). Clonal architecture was investigated in 17 patients using multiple color interphase fluorescence in situ hybridization analysis, which showed that the translocation was acquired as a secondary abnormality in ten patients, in four patients the etiology was undetermined and in three patients it was observed in a separate clone from the primary chromosomal rearrangement. These findings demonstrate the co-existence of immunoglobulin heavy chain locus translocations with other primary chromosomal rearrangements either in the same or separate clones, which may have prognostic significance in B-cell precursor acute lymphoblastic leukemia. Clinical trials: UKALLXII: Study ID n. ISRCTN77346223 and ALL2003: Study ID n. ISRCTN07355119     

Expression of CD20 on acute lymphoblastic leukemia cells in children

CD20 determinant expressed on B precursors is associated with regulation of proliferation, apoptosis and maturation of these cells. The acute lymphoblastic leukemia "common" type (cALL) based on expression of CD20 is subdivided in type I and II. However, the clinical significance of CD20 expression on cALL and significance of cALL type I and II discernment are not fully elucidated. The association of CD20 expression with the expression of multidrug resistance molecule (MDR), CD34, atypical immunophenotypes of leukemia cells and response to induction therapy were determined in the group of 147 patients with acute lymphoblastic leukemia (ALL) B progenitor type (ALL-proB -14 patients) and common type (cALL-133 patients). The expression of CD20 on leukemia cells was studied routinely at diagnosis before the therapy. This expression was noted on leukemia cells of 6 ALL-proB patients (42.8%) and 66 cALL patients (49.6%). The expression of CD20 showed no association with the expression of CD34, CD22 and MDR. The reverse association was observed between CD20 expression and the presence of co-expression of myeloid (CD13, CD33, CD65, CD15) and T lymphoid determinants (CD2, CD5, CD7) on leukemia cells. The effect of induction therapy analyzed as time of blast cells cytoreduction in peripheral blood and time of reaching the complete remission showed the slower clearance of peripheral blood from blast cells associated with expression of CD20. There was no association of CD20 expression with the time of reaching the hematological remission. The above results suggested a "protective" role of CD20 against co-expression of other determinants (myeloid and lymphoid) and no association with the results of induction therapy.     

Veno-occlusive disease of the liver during induction therapy for acute lymphoblastic leukemia

Veno-occlusive disease (VOD) of the liver, also termed as sinusoidal obstruction syndrome, constitutes a well-known complication of high-dose cytoreductive chemotherapy prior to allogeneic or autologous bone marrow transplantation and is associated with the intensity of treatment [1]. On the contrary, there is only one report of VOD during induction therapy for acute lymphoblastic leukemia in a patient with Marfan syndrome, who was successfully treated with defibrotide [2]. In this article, we present the first fatal case of VOD during induction therapy for acute lymphoblastic leukemia.