<prompt> B ALL is due to -T cellsImmature B cellsImmature T cellsBoth T B cells  <response>: Ans. is b i.e., Immature B ceils Acute lymphoblastic leukemialvmphomao Acute lymphoblastic leukemia ALL encompasses a group of neoplasms composed of immature, precursor B Pre-B orT Pre-T lymphocytes referred to as lymphoblast.o Majority 85 of all ALLs are precursor B-cell tumors that typically manifest as childhood Leukemia with extensive bone marrow and variable peripheral blood involvement,o The less common precursor T-cell ALLs tend to present in adolescent males as lymphomas, often with thymic involvement.o Peak incidence of Pre B-celJ ALL is evident between 3-5 years and ALL is the most common childhood cancer.o PreT-cell ALL occurs in adolescent male.o Morphology of tumor cell lymphoblast.Having scant cytoplasm and nuclei somewhat larger than those of small lymphocytes.The nuclear chromatin is delicate and finely stippled and nucleoli are either absent or inconspicuous.Contain cytoplasmic aggregates of Periodic acid schiff tPASi positive material.Immunophenotvpe of B cell ALLImmunophenotvpic classification of acute lymphoblastic leukemiaPre T cell ALLTdT, CD2. CD3, CD5XD4, CD7, CD8Early pre BTdT, DR, CD 10, CD 19, CD24Pre B cellTdT, DRXD10, CD19, CD20, CD24, CIgB CellDR, CD 19, CD20, CD24, SIg 