Unit 17

Pre-text assignments

1 Learn the key words and phrases:

leukocytes, myloid leukemia, red bone marrow, lymphoid leukemia, lymph nodes, mature, neutrophils, crowd out, invade, weaken, counteract

2 Find substitutes for the given phrases:

1) fatal disease with marked increase in

number of blood leukocytes a) myeloma

2) inflammation of the skin b) cytopenia

3) a tumour composed of cells of the c) lupus erythematousus

type normally found in the bone d) occult

marrow e) merrow

4) deficiency in the cells of the blood f) leukemia

5) obscure or hidden from sight

6) soft material filling most of

the cavities and cancel of the bones

Leukemia

Leukemia is a form of cancer characterized by an uncontrolled production of specific types of leukocytes. There are two major types of leukemia. Myeloid leukemia results from an abnormal production of granulocytes by the red bone marrow, while lymphoid leukemia is accompanied by increased formation of lymphocytes from lymph nodes. In both types, the cells produced usually fail to mature into functional cells. Thus, even though large numbers of neutrophils may be formed in myeloid leukemia, these immature cells have little ability to phagocytize bacteria, and the patient has a lowered resistance to infections.

Eventually, the cells responsible for the overproduction of leukocytes tend to spread (metastasize) from the bone marrow or lymph nodes to other parts, and as a result white blood cells are produced abnormally in tissues throughout the body. As with other forms of cancer, the leukemic cells finally appear in such great numbers that they crowd out the normal, functioning cells. For example, leukemic cells originating in red bone marrow may invade other regions of the bone, weakening its structure and stimulating pain receptors. AIso, as the normal red marrow is crowded out, the patient is likely to become anemic and develop a deficiency of blood platelets (thrombocytopenia). The lack of platelets is usually reflected in an increasing tendency to bleed.

Leukemias are also classified as either acute or chronic. An acute condition appears suddenly, the symptoms progress rapidly, and death occurs in a few months if the condition is untreated. Chronic forms begin more slowly and may remain undetected for many months. Without treatment, life expectancy is about three years.

The greatest success in treatment has been achieved with acute lymphoid leukemia, which is the most common cancerous condition in children. This treatment usually involves counteracting the side effects of the condition, such as anemia, hemorrhaging, and an increased susceptibility to infections, as well as administering chemotherapeutic drugs.

Although acute lymphoid leukemia may occur at any age, the chronic form usually occurs after fifty years of age. Acute myeloid leukemia also may occur at any age, but it is more frequent in adults; chronic myeloid leukemia is primarily a disease of adults between twenty and fïfty years of age.

Post-text assignments

1 Answer the qustions using the topical unit:

1 What is leukemia?

2 Distinguish between myeloid and lymphoid leukemia.

3 Is acute leukemia easily found?

4 Where can the symptoms of the disease appear?

5 How is acute leukemia developed?

6 What factors are involved in the course of acute leukemia?

2 Translate the following terms and use them in making sentences of your own:

chemotherapy, granulocytic, dysfunction, hematologist, marrow, immunoglobulin, lymphatic, disorder

3 Discuss the problems of leukemia speculating about the chances of finding an effective treatment in the foreseeable future.