Determination of myeloid antigen expression on childhood acute lymphoblastic leukaemia cells: discrepancies using different monoclonal antibody clones

Hematological, clinical, immunophenotypic characterization, and treatment outcomes of prognostically significant genetic subtypes of B-lineage acute lymphoblastic leukemia: A report of 1021 patients from India

BACKGROUND

The published literature on hematological, clinical, flowcytometric-immunophenotyping, and minimal residual disease outcomes of the prognostically important genetic subtypes of acute lymphoblastic leukemia (ALL) is scarce from low-income countries. For newer classifications such as BCR::ABL1-like ALLs, the scarcity of patient-level data is even more pronounced.

METHODS

The authors performed comprehensive detection of recurrent gene fusions and BCR::ABL1-like ALL cases followed by immunophenotypic profiling and obtained clinical outcome parameters for a large cohort (n = 1021) of patients from India. This cohort included a significant number of patients with BCR::ABL1-like ALL subtype and other genetic subtypes of ALL.

RESULTS

Patients with BCR::ABL1-positive and BCR::ABL1-like ALL were significantly older, had male preponderance, and expressed a higher white blood cell count than BCR::ABL1-negative cases (p < .05). Logistic regression modeling of B-lineage-ALL (B-ALL) subtypes revealed that cluster of differentiation (CD)36 is a strong statistically significant predictive marker of BCR::ABL1-like ALL (p < .05). Furthermore, patients with BCR::ABL1-like ALLs show a significantly higher frequency of CD36 expression compared to BCR::ABL1-negative ALLs (p < .05). In terms of clinical symptoms, lymphadenopathy is a strong statistically significant predictive marker in BCR::ABL1-like ALLs compared to BCR::ABL1-negative ALL cases (p < .05). In terms of treatment outcomes, minimal residual disease (MRD) positivity in BCR::ABL1-positive ALL cases were statistically significant (p < .05), and BCR::ABL1-like ALL cases had high MRD-positivity as compared to BCR::ABL1-negative ALL cases but did not show statistical significance.

CONCLUSIONS

The findings evince the use of novel therapies and personalized treatment regimens to improve the overall survival of the newer incorporated entities in B-ALLs. This is the first report characterizing the hematological, clinical, flowcytometric-immunophenotyping, and minimal residual disease outcomes of the prognostically significant subtypes of ALLs in patients from India.

PLAIN LANGUAGE SUMMARY

Characterizing the hematological, clinical, flowcytometric-immunophenotyping, and minimal residual disease outcomes of the prognostically significant subtypes (n = 1021) of acute lymphoblastic leukemia (ALLs) in patients from India. We have made two independent logistic regression models of cluster of differentiation (CD) markers and clinical symptoms to differentiate prognostically significant subtypes of ALLs. Logistic regression analysis of CD markers revealed CD36 as a strong predictor in BCR::ABL1-like ALL cases compared to BCR::ABL1-negative ALL cases. Logistic regression analysis of clinical symptoms revealed lymphadenopathy significantly predicts BCR::ABL1-like ALLs (p < .05). In terms of treatment outcomes, BCR::ABL1-positive ALL had statistically significant minimal residual disease (MRD) (p < .05), and BCR::ABL1-like ALL cases had high MRD-positivity but did not show statistical significance as compared to BCR::ABL1-negative ALLs.

Immunophenotypic, Cytogenetic and Clinical Features in Chinese Adult Acute Lymphoblastic Leukaemia (ALL) Patients

Introduction: This study sought to investigate the immunophenotypic subtype profiles of 110 Chinese adult patients with acute lymphoblastic leukaemia (ALL) and its association to cytogenetics and the clinical features. Materials and Methods: A total of 110 adult patients with ALL were immunophenotyped by CD45/SSC double parameters and 4 colour flow cytometry. Seventy-three cases were also subjected to karyotype analysis by R-banding technology. The clinical and laboratory data of 110 ALL patients were retrospectively analysed. Results: Of all the patients, 21.8% were identified as T-ALL, 78.2% as B-ALL. Abnormal karyotypes were detected in 37 out of 73 (50.7%) cases and the most common cytogenetic abnormality was the Philadelphia (Ph) chromosome, which was found in 23.3% (17/73) of the cases. Myeloid antigen (MyAg) expression was documented in 47.3% of the 110 adult ALL cases analysed and CD13 was the most commonly expressed MyAg in ALL patients (32.1 %). No difference was observed in the expression of MyAg between the groups of patients with T-ALL (45.8%) and B-ALL (47.7%). Our data showed that older age, higher CD34 positivity and lower proportion of patients with splenomegaly were found to be correlated with MyAg+ ALL, and that patients with Ph+ B-ALL were older, presented with higher haemoglobin level and higher CD34 expression. No statistical difference was noted in complete remission (CR) rate, relapse rate, induction mortality or total death rate among My+ and My-, Ph+ and Ph-, or B-ALL and T-ALL patients. Conclusion: Our results indicate that the distribution of ALL in Chinese adult patients was similar with the general distribution pattern in the other countries, and the expression of MyAg in patients with T-ALL and B-ALL was comparable. Both the expression of MyAg and the presence of Ph chromosome in adult ALL were significantly associated with median age and CD34 expression while not with the response to induction treatment. Key words: Biological characteristics, Cytogenetics, Immunophenotype

Aberrant phenotype in Iranian patients with acute myeloid leukemia

PURPOSE

The aim of this study was to evaluate the incidence of aberrant phenotypes and possible prognostic value in peripheral and bone marrow blood mononuclear cells of Iranian patients with AML.

METHODS

56 cases of de novo AML (2010-2012) diagnosed by using an acute panel of monoclonal antibodies by multiparametric flowcytometry. Immunophenotyping was done on fresh bone marrow aspirate and/or peripheral blood samples using the acute panel of MoAbs is stained with Phycoerythrin (PE) /fluorescein isothiocyanate (FITC), Allophycocyanin (APC) and Peridinin-chlorophyll protein complex (perCP). We investigated Co-expression of lymphoid-associated markers CD2, CD3, CD7, CD 10, CD19, CD20 and CD22 in myeloblasts.

RESULTS

Out of the 56 cases, 32 (57.1%) showed AP. CD7 was positive in 72.7% of cases in M1 and 28.5% in M2 but M3 and M4 cases lacked this marker. We detected CD2 in 58.35 of M1cases, 21.40% of M2 cases, 33.3 of M3 and 20% of M5; but M4 patients lacked this marker. The CBC analysis demonstrated a wide range of haemoglobin concentration, Platelet and WBC count which varied from normal to anaemia, thrombocytopenia to thrombocytosis and leukopenia to hyper leukocytosis.

CONCLUSIONS

Our findings showed that CD7 and CD2 were the most common aberrant marker in Iranian patients with AML. However, we are not find any significant correlation between aberrant phenotype changing and MRD in our population. Taken together, this findings help to provide new insights in to the investigation of other aberrant phenotypes that may play roles in diagnosis and therapeutic of AML.

Aberrant expression of CD13 identifies a subgroup of standard-risk adult acute lymphoblastic leukemia with inferior survival

BACKGROUND

The standard-risk (SR) subgroup of acute lymphoblastic leukemia in adults (aALL) is a heterogeneous category, with a 20% to 40% relapse rate and a wide range of relapse-free survival (RFS) and overall survival (OS). There is a need to identify at the outset those patients with SR-aALL who are likely to have shorter RFS and OS, so they can be treated more aggressively.

PATIENTS AND METHODS

Flow cytometric data of 81 patients with SR-aALL treated with a standardized protocol were retrospectively analyzed. Thirty-two patients (40%) relapsed; the median RFS and OS were 12.5 months (range, 1-136 months) and 30 months (range, 3-235 months), respectively. Twenty-six patients survived ≥ 48 months.

RESULTS

Expression of myeloid antigen CD13, using the conventional ≥ 20% threshold and a lower ≥ 5% threshold, was seen in 17 (29%) of 59 and 29 (49%) of 59 patients, respectively, whereas dual expression of CD13 and CD33 was seen in 8 patients. CD13 positivity at ≥ 20% and ≥ 5% threshold was associated with a shorter RFS (P = .0158 and P < .0001, respectively) and OS (P = .0072 and P < .0001, respectively). Dual expression of CD13 (at ≥ 5% or ≥ 20% threshold) and CD33 was associated with inferior OS (P = .0038 and P = .0032, respectively) and RFS (P = .0705 and P = .2516, respectively). For ≥ 20% and ≥ 5% threshold of positivity, 16 of 42 and 28 of 42 who survived < 48 months were positive, compared with 1 of 17 and 1 of 17 who survived ≥ 48 months (P = .0133 and P < .0001, respectively).

CONCLUSION

Aberrant expression of CD13 in ≥ 5% of blasts of patients with SR-aALL is an adverse prognostic factor, delineating a subgroup of patients with SR-aALL that should be considered for more aggressive treatment.