Characterization of Acute Lymphoblastic Leukemia Subtypes in Moroccan Children

Abstract

We present the incidence and the immunologic characteristics of acute lymphoblastic leukemia (ALL) subsets in Moroccan children. We studied 279 unselected patients below the age of 18 years with newly diagnosed ALL. Cases were classified according to immunophenotype: 216 (77.42%) precursor B-cell phenotype (pB-cell), mature B-cell in 4 (1.43%), and T-cell in 59 (21.15%) cases. The subclassification using the CD10 antibody revealed 197 cases pB-ALL CD10+ (91.2%) and 9 cases T-ALL CD10+ (19.2%). The age distribution showed a peak in incidence between 3 and 5 years among the pB-cell ALLs subtype. There was a significantly higher frequency of males in the T-ALL subset (M/F ratio: 2.93 : 1) and more females in the T-ALL CD10+ subset when compared with the T-ALL CD10– subset. All tested pB-cell-lineage ALLs expressed CD19, CD79a, and surface CD22, terminal deoxynucleotidyl transferase (TdT) was detectable in 89.9% of cases, and cells in 74.1% of cases express CD34. All tested T-lineage ALL cells have surface CD7 and cytoplasmic CD3 (cCD3) antigens, CD5 was found in 98.2% cases, and 70.5% express TdT. CD1a, surface CD3 (sCD3), and CD4 are detected in more than 80% of cases; this frequency is higher than the 45% generally observed. Myeloid antigens occur more frequently and were expressed in 124 (57.4%) of pB-cell-ALL cases and 20 (33.9%) of T-cell ALL cases. Our results show that the distribution of ALLs in Moroccan children is similar with the general distribution pattern in developed countries except for the high frequency of T-ALL phenotype. The phenotypic profiles of our patients are close to those reported in literature for B-lineage ALLs; for the T-cell ALL subgroup, the blast cells express more CD1a, surface CD3, and CD4 while expressing less TdT. The high frequency of CD1a expression resulted in an excess of the common thymocyte subtype.

Clinical, hematological, and laboratory presentation of acute lymphoblastic leukemia of children in Diyala province/Eastern Iraq

“…16,18,19 In this study, ALL incidence was observed more in male gender (M: F= 1.3:1) matching the finding of further studies, whereas it reached 1.84:1 in others. 11,15,[20][21][22] The commonest complaint of the study patients was fever, followed by bone pain, weight loss, and fatigability, these were consistent with findings by other studies. 23,24 Bone pain was presented in 22 patients (40%), it was variably reported by many studies (19-67%), Joint pain was present in one (1.8%) patient only (ankle joint), whereas it was presented more (6-9.3%) by other studies.…”

Flowcytometric Immunophenotypic Profile of Acute Leukemia: Mansoura Experience

“…Immunophenotypic criteria of B-ALL All our B-ALL cases express CD19 while TdT was expressed in 97.4% and this found to be similar to Bachir et al [25]. In B-ALL, myeloid aberrant phenotype has been …”

“…Positivity of CD3 was 38.5% and like some previous studies was not confirmed as the most sensitive marker, which is limited by the fact that it is uncommonly expressed on the surface of T-ALL and is almost always present abundantly in the cytoplasm of these cells [13]. All T-ALL cases in this study were negative for HLADR and this incidence is much higher than reported elsewhere [13,25] which may be explained by low number of cases in our study. Regarding aberrant B-cell marker expression on T-ALL, it was reported that CD10 and CD19 are expressed in various percentages on such cases (19-43% and 0-2.3%, respectively) [13,19].…”

The Role of Kappa and Lambda in Subclassification of B Cell Lymphoblastic Leukemia in Sudanese Patients Using Flow Cytometry

“…Our study confirmed that early pre-B ALL lack cytoplasmic and surface immunoglobulin and Kappa and Lambda while pre-B exhibit cytoplasmic immunoglobulin which agreed with Fatima Bachir et al study that indicated the same result [16].…”

“…This result concordant with Fatima Bachir et al that showed 100% of cases with surface Ig (lambda/kappa) and this emphasizes the importance of immunoglobulin and light chain testing in B-ALL for sub classification [16].…”