What is acute lymphocytic leukemia?

Leukemia is an umbrella term that includes many different types of blood cancer, each one of them depending on what cell line is affected. Leukemia is a complex ailment that may include several alterations and severe symptoms that usually require hospitalization until the patient is stable. Acute lymphocytic leukemia, also known as acute lymphoblastic leukemia, is the most common subtype of leukemia, and the most common type of cancer in children.
What is it about? How is it diagnosed and treated? We are going to cover each one of these points in the next paragraphs.
Also known as acute lymphoblastic leukemia or ALL, it is a malignant disease that affects the bone marrow. This is the place where blood cells are formed, starting from lymphoid precursors that become blood cells over time. It features an accelerated growth of lymphoblasts that stay immature and become arrested in their development. As the disease continues and aberrant lymphoblast proliferate further, other blood cells become affected as well.
Even though precursors of red blood cells, neutrophils, and platelets are not affected in acute lymphocytic leukemia, the bone marrow slows down their production to keep on creating aberrant lymphoblasts. Thus, patients will not only have a reduction of fully functional lymphocytes but also a reduction of neutrophils (neutropenia), platelets (thrombocytopenia), and red blood cells (anemia).
Moreover, as it happens in all types of cancer, acute lymphoblastic leukemia may infiltrate to other tissues outside of the bone marrow. The most common sites are lymph nodes, the spleen, and liver, which often results in enlargement of each organ (lymphadenopathy, splenomegaly, and hepatomegaly, respectively).