Rare adult acute lymphocytic leukemia with CD56 expression in the ECOG experience shows unexpected phenotypic and genotypic heterogeneity

Abstract

Expression of CD56, a marker of natural killer (NK) cells, in acute lymphocytic leukemia (ALL) is rare and, to date, has been described only in non-B lineage ALL. Among 194 patients with CD56 analysis on the ongoing Eastern Cooperative Oncology Group (ECOG) ALL trial, E2993, 6 cases of CD56+ ALL were found (3.1%) with a median of 95% of blast cells expressing CD56, compared with a median of 1% of blast cells in CD56- ALL (P = 0.0001). FAB-L2 characteristics dominated, without granulation. Blast cells from four CD56+ patients expressed T-cell antigens at variable levels of maturation. A clonal rearrangement of the T-cell receptor beta (TCRbeta) gene was detected only in one patient. TCRbeta variable gene usage studies in this and one other CD56+ ALL patient demonstrated a significantly perturbed usage pattern in both patients when compared with control lymphocytes. The two remaining cases typed as early pre-B ALL (CD19+, CD10+), with one case co-expressing CD7. Cytogenetically, 4 patients were normal, 1 complex abnormal, and 1 Philadelphia chromosome positive. Epstein-Barr virus (EBV) sequences were detected in one T- and both B-lymphoid cases. Our data suggest that CD56 is expressed at a precursor stage common to the T- and the B-cell lineage.

Clinical Significance of Co-expression of Aberrant Antigens in Acute Leukemia: A Retrospective Cohort Study in Makah Al Mukaramah, Saudi Arabia

“…The frequency of aberrant myeloid antigen expression in the studied ALL group was 36.4%, our results are in accordance to 39% reported by Bhushan et al (2010), comparable to 21.2% (Paietta et al, 2001), and 55% reported by Wu et al (2007), while in contrast to others references (Pui et al, 1998;Vitaleet al, 2007).…”

“…In this work, CD56 was detected in 9% in ALL, mildly lower frequency of CD56 expression were reported earlier; 5% (Seegmiller et al, 2009), 3% (Paietta et al, 2001) and 2.2% (Hussein et al, 2011). We reported 4 cases with hyperdiploidy all were expressing CD34 and two of them lost CD45 in agreement with others who found higher CD34 expression in B-ALL with hyperdipolidy and under expression or loss of CD45 (Behm et al, 1992;Seegmiller et al, 2009).…”

“…Several smaller case series and case reports have demonstrated CD2, CD5, CD7 expression in B-ALL (Paietta et al, 2001;Peterson et al, 2007;Ahmed et al, 2008). Up to our knowledge, we are the first to find a statistically significant higher bone marrow blast % at presentation and day 14 with p value (0.005, 0.046) respectively in the ALL cases that expressed aberrant antigens, which could be considered as high risk factors.…”

CD56 expression in T-cell acute lymphoblastic leukemia is associated with non-thymic phenotype and resistance to induction therapy but no inferior survival after risk-adapted therapy

“…[5][6][7] In T-cell acute lymphoblastic leukemia/lymphoma (T-ALL/LBL) CD56 expression has been reported for a small number of cases and an association with worse outcome has been suggested. [8][9][10][11] The expression of other single antigens such as CD2, CD10 or myeloic antigens has been evaluated for their prognostic impact in T-ALL. [12][13][14] However, the immunological subtype is still the leading prognostic factor, with thymic T-ALL having a considerably better prognosis than pre-T or mature T-ALL.…”

Leukemia and Lymphoma of Natural Killer Cells

“…Differentiation of nonnasal NK-cell lymphomas occurring in the skin or soft tissue from extramedullary AML is particularly important for prognostic and therapeutic decisions. However, in acute lymphoblastic leukemia CD56 expression is relatively rare 134,[145][146][147] . CD56 is also expressed in a subset of T-cells, as well as 5-20% of peripheral T-cell lymphomas [148][149][150][151][152][153] .…”