LEUKEMIA

Leukemia

Leukemia

Introduction

Leukemia is a cancer of the white blood cells. Lymphocytes are members of a specific group of white blood cells that function to help the body fight infections and are part of the immune system known as the lymphoid cells. Like other types of cells in the blood, lymphocytes originate in the bone marrow in immature forms. Before developing into fully mature lymphocytes, these cells are called lymphoblasts (Frankel, 2006). A fast, unregulated overgrowth of lymphoblasts that neither develop nor function normally is defined as acute lymphoblastic leukemia,also known as acute lymphocystic leukemia, acute lymphoid leukemia, or simply ALL (Uma, 2006).

Leukemia is a cancer of the blood that causes the cell lines in bone marrow to grow abnormally. This term refers mostly to white blood cells (leukocytes) and is used rarely in reference to red blood cells and platelets. White blood cells are the cells in the blood and tissues that protect animals from infection.

Discussion

All three groups of blood products—white blood cells, red blood cells, and platelets—are produced in the bone marrow. When the white blood cells outgrow the red blood cells and platelets, the other two groups are not able to produce their respective blood products because of the lack of room in the bone marrow. Thus, the signs and symptoms of leukemia reflect the shift of cells in the bone marrow, which normally allows growth of red blood cells, platelets, and white blood cells to the uncontrolled growth of one line of cells (Uma, 2006). Many people with leukemia will present with weakness, fatigue, bruising, infection, and abnormal bleeding such as nose bleeds or around the gums. The fatigue is from the decreased number of red blood cells, also known as anemia (Dambro, 2007). The bleeding and bruising is from a decreased number of platelets, which help the blood to clot. The increased number of infections is due to the dysfunctional white blood cells. Although there are more white blood cells than normal in the blood in leukemias, they do not function like a normal protective cell. Other nonspecific symptoms include fever, night sweats, and loss of appetite (Ching 2009).

Diagnosis of leukemia is usually made from a complete blood count (CBC), a smear of the blood onto a microscope slide (peripheral smear), a bone marrow biopsy plated onto microscope slides, and genetic testing for cell markers (CD or cluster of differentiation) or translocation. Translocation is the joining of two halves of two different chromosomes that do not belong together and is usually determined by a process call fluorescent in situ hybridization (FISH) (Elter, 2006). FISH is completed by looking at the 23 sets of human chromosomes and attaching a fluorescent marker to genes that are found on certain chromosomes. If the two markers end up on the same set of chromosomes, then there was no translocation. However, if the markers end up on different sets of chromosomes, then translocation is present (Damle, 2008). Examples of translocation would be the merging of a part of chromosome 9 with a ...