Abstract Background Childhood pre-B acute lymphoblastic leukemia (ALL) is a bone marrow (BM) derived disease. which often disseminates out of the BM cavity. where malignant cells to a variable degree can be found circulating in the peripheral blood (PB). Normal pre-B cells are absolutely dependent on BM stroma for survival and differentiation. https://icemanvideoesgames.shop/product-category/collections/