According to the Cancer Book from the American Cancer Society, Leukemia is a cancer of the blood. It was first identified as a new disease in around 1830 in Germany. The scientific term, “leukemia,” comes from the Greek words that mean “white blood.” The disease is described as a cancerous disorder not just of the blood itself, but also of the organs that produce the blood cells in the body. The organs are mainly the bone marrow and the lymph system, where normal red and white cells, lymph cells, and platelets grow before entering the bloodstream. Normal cells usually go through the same process but with differences in rate, number, and function ability. With the disease, the bone marrow will not be able to produce the sufficient levels of red blood cells and platelets, while the white blood cells will produce so rapidly that the cells will not become mature enough to fight off infections. As the disease progresses, the whole blood system will become useless due to the vast amount of immature cells produced. If a person with the disease is not treated, there will be excessive bleeding and infections until the body reaches the point where it becomes defenseless. The body will make minor injury or infection very serious. Leukemia itself does not always kill people. Instead, people die from infections such as small virus or bacteria because there are not enough normal white blood cells in the body. Also, people could die form internal bleeding, which could have been prevented by the platelets. Leukemia appears more commonly in adults then children. A survey in 1989 stated that approximately 25,000 new cases of the disease are diagnosed annually in the United States, 22,500 of them are adults and only 2,500 are children. It also shows that men are affected by leukemia 30 percent more frequently than women. Ten years ago, about 17,000 people die from the disease each year. Many of the advanced industrial nations have increased the study of leukemia since the 1930s.
In the Personal Health Report, the information stated that there are two major types are leukemia: “Lymphocytic leukemia which involves lymphoid committed cells which form and mature in the lymphatic system, and granulocytic leukemia which affects myeloid committed cells which form and mature in the bone marrow” (355). Each of the two types can occur in either acute or chronic form. Acute form usually affects young cells that are still in the process of growing; they can divide very quickly and may speed the progress of the disease. The chronic form involves the mature cells that reproduce in a low rate or the ones that have stopped dividing.
According to the Home Medical Guide, acute lymphocytic leukemia is most commonly seen in children between the age of two and nine. In this type of leukemia, males are affected more frequently than females. Before treatment was available, the average survival rate is only 5 to 6 months. As treatment developed, more then 95 percent of all children are putted into complete remission. Both adult and childhood disease can be cured in around four years, and the therapy can be discontinued. Chronic lymphocytic leukemia is the most common form of cancer found in the industrialized countries. Like acute lymphocytic, it occurs more frequently in males then in females. The patients that are affected by chronic lymphocytic leukemia are usually older then any other patients with different types of leukemia. The cause of this specific type of disease is still unknown:
Strong evidence points to problems of function and control in the immune system
diagnosis is very often discovered by accident in the course of routine blood testing for
other medical reasons, since fully 25 to 30 percent of newly diagnosed patients have no
symptoms?the degree of bone marrow infiltration by small lymphocytes is a much more
accurate sign of degree of disease. (452)
According to the Home Medical Guide, acute granulocytic leukemia usually occur in older ages: “The typical patient is thirty to sixty years old, the frequency of the disease increasing with age. The natural course of untreated this disease leads to an average survival of only two to five months” (451). With chemotherapy, the survival rate can be lengthened to about 5 years. Around 75 percent of the patient can be cured with a complete remission. This type of leukemia can cause heart attacks and strokes by blocking the arteries: “It is treated by removing large numbers of white cells from the patient’s blood and increasing the intensity of the chemotherapy”(453). Over 50 percent of the patients are found with abnormalities in the chromosomes: “Evidence strongly suggests that each patient’s individual chromosomal makeup has a strong direct bearing on prognosis” (453). Patients that have abnormal genes in their leukemia cells usually have the disease. Chronic granulocytic leukemia occurs in people with ages forty to sixty. The disease starts out very slowly. Patient will not notice anything wrong until after three to six months. Many organs such as the liver, spleen and lymph nodes will enlarge in over half of the patients. The study of chromosomes are important in this type of leukemia: “The so-called Philadelphia chromosomes, the first abnormal chromosome found in the leukemias, occurs in over 90 percent of patients” (454). Applying therapy may reduce of Philadelphia in the white blood cells.
In the Cancer Book, the author explained that the basic cause of leukemia is still unknown. Factors such as exposure to radiation, chemicals, and certain drugs may cause the disease: “Certain chemicals, such as benzene, have long been known to cause damage to bone marrow calls which form the blood, and it is logical to conclude they can also cause a cancer in those cells” (378). Also, the genes called oncogenes may be directly involved in the development of many types of cancers, including leukemia:
Oncogenes are cancer-causing genes that are part of many people’s normal
genetic makeup. These genes can apparently be activated under circumstances
that has not yet identified?by identifying and understanding specific oncogenes,
people who are considered at risk can be identified long before a cancer begins.
Although this is a long way in the future?the concept of the oncogene has given
scientists a new and fundamental approach to the study of cancer that much
believe will yield fruitful result. (379)
The book further explained the causes of leukemia, and it says the hereditary causes of the disease are still far form being fully understood. There are chances that close relatives of leukemia patients have a risk of getting the disease. The greatest possibility is found in the identical twin of a child who has the acute leukemia before the age of eight: “Approximately 20 percent of these individuals will develop the disease within one year of their twin’s diagnosis” (379). This shows that genetics are playing an important role in the disease. But whether heredity is also involved in all cases is still an unanswered question.
According to the Personal Health Report, leukemia may be caused by other types of disease that damage the bone marrow, or anticancer drug used to treat other variety of cancer: “Diseases that cause severe depression of the marrow, such as aplastic anemia, are associated with a high incidence of leukemia.” (356) Patients that take anticancer drugs for treatment of diseases may have a chance of getting leukemia because the patients received cancer chemotherapy over a long period of time: “Up to 10 percent of patients with Hodgkin’s disease who have been intensively treated with chemotherapeutic drugs may ultimately display signs of an acute granulocytic leukemia” (356). There is antileukemia therapy for Hodgkin’s disease. They are far more effective and outweigh the chance of developing leukemia later on.
Fever may be the most common symptom. It is usually caused by an infection of
the skin, lung, or urinary tract, but it also may be due directly to the leukemia
itself or to the release of compounds by the abnormal white cells. Infections are
frequently because the leukemic white cells cannot protect against invasion by
bacteria or other organic causes of disease, and too few normal white cells
remain to do so. (846)
The book also states that since these symptoms are involved with many illnesses, doctors do not always have suspicion of leukemia. Early detection of chronic lymphocytic leukemia is often found in elders that are being examined for other medical problems. On the other hand, acute leukemia can occur very suddenly, especially in children because it seems like a flu or cold: “Common symptoms of the leukemias do not seem to be a direct result of the increase and spread of leukemia cells. Instead, the functioning of the remaining normal elements of the blood and bone marrow is impaired” (847). Up to one third of the patient with cancer in blood have normal or low circulation white blood counts. In leukemia, the bone marrow is too crowded with white blood cells that it cannot move out into the bloodstream. Bleeding problems are not serious in the early period of the disease, but they can become serious as it progresses: “Bleeding is usually mild at first, with only small patches of black and blue discoloration under the skin. Later, the suppression of the platelet-forming cells in the bone marrow reduces the number of platelets produced” (848). Sometimes, patients may feel pain in the joints and bones, but it is not a major effect. Also, other organs in the body such as the liver, heart, kidney, brain and the digestive system will continue to function quite normal under the early stage of the disease.
According to the Cancer Book, all the patients with leukemia must have a record from all the physical examinations and laboratory investigations. The record will provide the physician a base line for treatment and to see if there are any other kinds of medical problem. Usually leukemia can be suspected by the physician based on the patient’s history and other symptom: “The definitive diagnosis must be made by examination of the cells in the bone marrow” (382). Observation of blood samples can confirm the doctor with the suspect of the disease. Also, inserting a thin needle into the marrow-rich cavity, in the backbone or the breastbone can do a bone marrow test. The test take about 15 to 20 minutes and it can be performed in local clinics or doctor’s offices. The test may seem frightened to many patients, but it only involves a little discomfort in the back of the body.
The Cancer Book further states that if leukemia is confirmed, different types of study will be performed: “Immunologic tissue typing, blood typing, coagulation and transfusion studies will be done. This information is most valuable if acquired before transfusions have made it difficult to test the properties of the patient’s own blood” (382). Bone transplantation is dependent on the tissue typing. Brothers and sisters of the sick patient are strongly suggested to tissue typing because they will have a greater chance of success in the bone marrow transplantation.
In the Cancer Book, the information shows that the first treatment for all types of leukemia is chemotherapy. The purpose of this treatment is to destroy the lurkemic cells in the bone marrow. But at the same time, the normal cells are being destroyed. It is hoping that the destruction of the leukemic cells will let the body develop the bone marrow with new and healthy cells. Patients will receive combination of chemotherapeutic drugs. It depends on the types of leukemia the patients carry; a completed remission is possible in 50 to 90 percent of patients. The chemotherapy protocol is divided into three stages-induction, consolidation, and maintenance: “During the induction stage, the patient receives intensive chemotherapy in an attempt to induce a complete remission. The largest number of leukemic cells are destroyed at this time” (384). When the first remission is completed, the consolidation stage will take place: “The purpose of this stage is to eliminate any remaining leukemic eliminate any remaining leukemic cells” (384). The consolidation stage primarily uses the same drugs as in the induction stage. Both of the stages last about 2 to 3 months, depending on the patient’s response to the treatment. If the remission is succeed, the patient will enter the maintenance stage: “It is designed to keep the patient in remission by preventing leukemic cells from returning to the bone marrow” (384). This stage will provide treatment to the patients while they can maintain a near-normal life style.
From the Mayo Clinic Family Health Book, there is an article that talks about other treatments beside chemotherapy: “A bone marrow transplant is another treatment option for patients with acute leukemia” (357). The procedure is still under investigation, and it is only performed at selected medical centers. This method is usually not being considered unless the chemotherapy is not effective. Before the transplantation, the patient will require to take ultrahigh doses of radiation and chemotherapy to destroy all blood-forming cells. The success rate for bone marrow transplants vary. The average survival rate is 10 to 15 percent. In further discussion, it is found that problems can occur after injection of the donor marrow: “The recipient’s immune system can reject the marrow transplant or the donor’s marrow, in its immunologically foreign environment, can reject the host” (358). For this reason, the closer the genetic makeup between the donor and host, the better the transplant will succeed. Some patients will try to match themselves with a donor from their family or closed relatives because it will give them a better chance of the transplant’s process. In the transplantation, the following steps will be done: “The donor’s cells are injected into the recipient’s bloodstream to re-seed the marrow with healthy cells. The leukemia patient is kept in isolation to diminish the chance of infection and is given transfusions and antibiotics as needed” (387). In the bone marrow transplantation, the donor’s cell is to develop into new healthy cells in the sick patient’s body.
According to the Cancer Book, great progress has been make over the last thirty years in treating the disease. An increasing number of patients are cured. Although the process of treatment is long and produces painful illnesses, but rate of success in remission and other methods are worthwhile for most patients.