Leukemia is termed as a type of cancer that affects blood cells, mostly affecting white blood cells. The prime role of white blood cells is to protect the body from bacteria, fungal, virus and any other foreign substances from invasion. Although most of the white blood cells are produced by the bone marrow, certain types are generated by the lymph node, spleen, and the thymus gland. As such, the white blood cells of a patient with leukemia are not able to function cogently. Moreover, the white blood cells of an individual with leukemia may also divide rapidly and eventually crowd out the healthy cells.

One of the criteria used to classify leukemia is its onset-either sudden or slow onset. In most cases, leukemia can be either acute or chronic. In the case of acute leukemia, the cancerous cells typically multiply at a very rapid rate. However, in the case of chronic leukemia, the condition progresses at a snail pace, and in most circumstances, early symptoms are mild. Secondly, Leukemia can also be classified according to the type of cells that are involved. While leukemia embracing myeloid cells is known as myelogenous leukemia, the other involving lymphocyte is referred to as lymphocytic leukemia (Verneda, et al, 2015).

Nonetheless, there are typically four types of leukemia. The first category is Acute Myelogenous Leukemia (AML), which is the most form of leukemia in the US. According to National Cancer Institute, AML affects about 21,000 children and adults annually. Secondly, Acute Lymphocytic Leukemia (ALL) is another type of leukemia that mainly affects 6000 children yearly in the US. The third is Chronic Myelogenous Leukemia (CML) that affects close to 7000 adults annually in the US. The last category is the Chronic Lymphocytic Leukemia (CLL) that affects about 15, 000 adults, mostly adults over the ages of 55 years (National Cancer Institute, 2012).

The main symptoms of leukemia include profuse sweating, tiredness and weaknesses, weight loss and swelling of the lymph nodes. Other symptoms include bleeding and bruising easily, fever, liver or spleen enlargement, and frequent infections. In most cases, leukemia affects body organs that are affected or infiltrated by cancer cells. Some of the organs of the body that can be affected by the condition include lungs, heart, kidney and testes (National Cancer Institute, 2012).

To diagnose leukemia, a physician will use blood tests, biopsies or imaging studies. If an individual is diagnosed with leukemia, the doctor will stage to determine a prognosis. A hematologist-oncologist will then treat the patient depending on the type and stage of cancer. Based on the kind and stage, leukemia is treated with chemotherapy, radiation therapy, immune therapy, targeted therapy or stem cell transplantation to replace the diseased bone marrow.