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What is Which of the following is not expressed in majority of cases of pediatric B-cell acute lymphoblastic leukemia? and explain in detail?
CD19 is a pan B-cell marker. CALLA (common acute lymphoblastic leukemia antigen) is CD 10. CD45 is known as leukocyte common antigen (LCA). Terminal deoxynucleotidyl transferase (TdT), a specialized DNA polymerase that is expressed only in pre-B and pre-T lymphoblasts, is positive in more than 95% of cases. CD7 is commonly expressed in T-cell ALL.