Acute lymphoblastic leukemia is a Neoplastic disease, that is, a type of cancer. This form of leukemia is the most common cancer in childhood, accounting for 80% of childhood neoplasms. Unlike other types of tumors, leukemias are not localized because they affect blood cells.
Therefore, although they share common symptoms with solid tumors, in this case the abnormal cells do not form a mass but circulate in the bloodstream. It is called lymphoblastic leukemia because it affects blood cells called lymphoid cells, which are what make up the immune system .
The blood cells are constantly renewed and synthesized in the bone marrow . The bone marrow is a flexible tissue that is found inside some bones. It is formed by hematopoietic stem cells or stem cells.
These stem cells have ability to form all blood cells in a process called hematopoiesis. It is a process of different stages mediated by different molecules that are known as colony stimulating factors.
Depending on which factor acts the cells that are formed will be one or the other. This process in which a stem cell gives rise to other cell types is called cell differentiation.
Under normal conditions, Hematopoiesis is a controlled process. When this control fails due to alterations in the genes or mutations, the cells grow uncontrollably. In addition, differentiation is slowed down so that normal blood cells do not form but the process ends earlier, giving immature cells called blasts.
These immature cells are the neoplastic cells that produce the leukemias. They are synthesized in the bone marrow and distributed throughout the body through the bloodstream. Depending on the stage that is altered, they will have some characteristics or others.
The hematopoiesis has two major differentiated pathways: the myeloid line and the lymphoid line When the neoplastic cells are from the myeloid line, it refers to myeloblastic leukemia. Similarly, if the affected cells are lymphoid, it is called lymphoblastic leukemia.
In the lymphoid line the main cells of the immune system are synthesized: the lymphocytes , so these cells are affected in acute lymphoblastic leukemia. There are different types of lymphocytes, depending on which are altered, there are several types of acute lymphoblastic leukemia.
The leukemias they will produce symptoms for different reasons. In general, they will be less specific, so to confirm leukemia it is necessary to perform specific tests. On the one hand, acute lymphoblastic leukemia has symptoms common to many types of neoplasms. It is known as constitutional syndrome:
As we said, all the blood cells are synthesized in the bone marrow. In uncontrolled blister growth leukemias occupy much of the bone marrow, so they can prevent other types of cells such as red blood cells, white blood cells and platelets from forming.
A Decreased red blood cells prevents oxygen from reaching the tissues properly, appearing a box of anemia . White blood cells are also part of the immune system, so these patients have a higher risk of infections. This is one of the most serious consequences of leukemia.
When we get a wound, the platelets contribute in an important way to stop the blood coming out. If these decrease, the subjects will have a higher risk of hemorrhaging.
As the picture progresses, symptoms arising from the involvement of other organs appear. Some examples are pain in the bones if bone marrow infiltration is important or skin lesions.
Near a 80% of patients have adenopathies, which are inflammations of the lymph nodes . They are oval formations that are part of the immune system and also become inflamed in other circumstances such as infections or other neoplasms.
These symptoms can make you suspect a leukemia but to confirm the picture it is necessary to demonstrate the existence of immature cells in the blood and in the bone marrow.
To do this, a peripheral blood sample is necessary to observe it under the microscope. It is called smear, and it can observe the characteristics and number of immature cells in blood.
To check the Functional alteration of the bone marrow can be done biopsy bone or a bone marrow aspirate. These tests allow you to see the cells directly. To speak of acute lymphoblastic leukemia, blasts must have lymphoid characteristics and assume at least 20% of all cells.