1.What is leukemia?
Leukemia is a malignant disease of hematopoietic tissue, commonly known as “blood cancer”, characterized by the tumorigenic proliferation of a certain type of leukemia cells in the bone marrow or other hematopoietic tissues, which can infiltrate various organs and tissues in the body, impairing the function of each organ and producing corresponding symptoms and signs. Clinical symptoms include anemia, fever, infection, bleeding, and enlargement of the liver, spleen and lymph nodes to varying degrees. Infantile cells may appear in the bone marrow and peripheral blood.
2. Why is leukemia called “blood cancer”?
Leukemia has common features with other malignant cancers. (1) Leukemia cells, like malignant tumor cells, can proliferate without restriction; (2) Leukemia cells, like other malignant tumor cells, can invade various organs of the body without hindrance, affecting the function of the organs and leading to systemic failure and death; (3) Leukemia can also manifest as local infiltration, forming masses like tumors. For example, skin infiltrating nodules and green tumors in the eye sockets, which are common in children. Therefore, people often refer to leukemia as “blood cancer”.
3. Why do people get leukemia?
The reason is not clear. Due to radiation, ionizing radiation, viruses, chemical substances (including poisons and drugs), and possible genetic or immune defects in individuals, hematopoietic cells can become malignant, and the malignant cells have defects in differentiation and maturation while maintaining the ability to divide and proliferate. Therefore, such malignant cells (leukemia cells) can continue to proliferate and accumulate in the body, diffusing from the hematopoietic tissue to the blood and a variety of organs throughout the body, resulting in the clinical manifestations of leukemia.
4.Is leukemia contagious?
Leukemia is not an infectious disease. Although the exact cause of human leukemia is still unclear and there are many theories about the pathogenesis of leukemia, there are no cases of leukemia being contracted through close contact with leukemia patients. Although some studies have found that certain viral infections, such as human T-lymphotropic virus type I (HTLV-1), can induce certain dintocellular leukemias, mainly due to mutations in the genes of the patients caused by the retroviral DNA that these viruses themselves hear. In addition, there have been reports of families in which several family members have had the same type of leukemia, but this is not due to mutual transmission, but rather to some genetic defect common to the family members. If leukemia is contagious, then the health care workers who are in close contact with leukemia patients are bound to be the first victims, but in practice, no leukemia is seen among the health care workers.
5. Is leukemia hereditary?
It should be said that not all leukemias have a genetic predisposition, but some leukemias are seen to be more likely to occur in certain ethnic groups (e.g. Caucasians), certain genetic defects (e.g. Down’s syndrome) and certain familial diseases (e.g. Fanconi anemia). In identical twins, if one person has acute leukemia, the other person has a significantly higher chance of developing acute leukemia (25%) than the general population (5/100,000). All of the above suggest that certain genetic factors may have an impact on the development of leukemia.
6. Is leukemia simply a disease of the white blood cells?
Leukemia is not simply a disease of white blood cells, because among the various series of the hematopoietic system (red, granular, monocytic, lymphatic, megakaryocytic, etc.), in addition to the leukocytic series (granular, monocytic, lymphatic), leukemia can also occur in other non-leukocytic series (megakaryocytic, red). In addition, regardless of the series of leukemia, in addition to the acute, neoplastic proliferation of cells at a certain stage in the series, there is also a suppression of the growth of other normal series of cells due to the effect of tumor cells on normal hematopoietic tissue. Therefore, any series of leukemia will eventually show varying degrees of anemia (erythrocyte reduction), bleeding (thrombocytopenia) and susceptibility to infection (abnormal white blood cell quantity and quality).