Types of tumours

A tumour fights with normal cells for nutrients and destroys the health cells and tissues the body needs. The tumour continues to grow in size and press onto nearby organs, or nerves causing pain. As tumour grows it attacks tissue and organs directly making them prone to infection, and finally destroying their ability to carry out their work properly. There are two kinds of tumors.

A benign tumour is not cancerous. The term "benign" implies a mild and nonprogressive disease. Indeed, many kinds of benign tumors are harmless to human health. However, some neoplasms is defined as "benign tumors" because they lack the invasive properties of a cancer may still produce negative health effects. Examples of this include tumors which produce a "mass effect" (compression of vital organs such as blood vessels), or tumors of endocrine tissues, which may overproduce certain hormones. Examples include thyroid adenomas, adrenocortical adenomas, and pituitary adenomas. Benign tumors typically are surrounded by an outer surface (fibrous sheath) that inhibits their ability to behave in a malignant manner. Nonetheless, many types of benign tumors have the potential to become malignant and some types, such as teratoma, are notorious for this. Benign tumors are very diverse, and may be asymptomatic or may cause specific symptoms depending on their anatomic location and tissue type. Symptoms or pathological effects of some benign tumors may include:

§ Bleeding or occult blood loss causing anemia

§ Pressure causing pain or dysfunction

§ Cosmetic changes

§ Itching

§ 'Hormonal syndromes' resulting from hormones secreted by the tumor

§ Obstruction, e.g., of the intestines

§ Compression of blood vessels or vital organs

Many benign tumors do not need to be treated at all. If a benign tumor is causing symptoms, presents a health risk, or causes a cosmetic concern хвилювання for the patient, surgery is usually the most effective approach. Most benign tumors do not respond to chemotherapy or radiation therapy, although there are exceptions.

A malignant tumour is cancerous; it is the uncontrolled growth of abnormal cells anywhere in a body. The abnormal cells are termed cancer cells, malignant cells, or tumor cells. Many cancers and the abnormal cells that compose the cancer tissue are further identified by the name of the tissue that the abnormal cells originated from (for example, breast cancer, lung cancer, colon cancer). Cancer is not confined to humans; animals and other living organisms can get cancer. Frequently, cancer cells can break away from this original mass of cells, travel through the blood and lymph systems, and lodge in other organs where they can again repeat the uncontrolled growth cycle. This process of cancer cells leaving an area and growing in another body area is termed metastatic spread or metastatic disease. For example, if breast cancer cells spread to a bone (or anywhere else), it means that the individual has metastatic breast cancer.

There are over 200 types of cancers; most can fit into the following categories according to the National Cancer Institute:

· Carcinoma: Cancer that begins in the skin or in tissues that line or cover internal organs.

· Sarcoma: Cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.

· Leukemia: Cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the blood.

· Lymphoma and myeloma: Cancers that begin in the cells of the immune system.

· Central nervous system cancers: Cancers that begin in the tissues of the brain and spinal cord.

The three most common cancers in men, women and children in the U.S. are as follows:

· Men: Prostate, lung, and colorectal

· Women: Breast, colorectal, and lung

· Children: Leukemia, brain tumors, and lymphoma

The incidence of cancer and cancer types are influenced by many factors such as age, sex, race, local environmental factors, diet, and genetics. Consequently, the incidence of cancer and cancer types vary depending on these variable factors.

Scientists have not yet pinpointed an exact cause for cancer. There is no one single cause that is responsible for all cancers. However, many factors have been identified that are likely to lead to the development of cancer in the body. These are called "risk factors for cancer" A risk factor is anything that raises a person's chance of getting a disease over a certain period of time.

Cancer specialists use different treatments to get rid of позбутися cancer - primarily: surgery, radiation therapy, chemotherapy and biotherapy. Depending on what type of cancer people have, they could have one kind of treatment or a combination of treatments. Others treatments for cancer include hormonal drugs, mainly in treating breast and prostate cancer, antibody treatment, which targets the surface of cancer cells with certain features, and blood stem cell transplant.

Treatment choices for a person with cancer depend on three things:

1. the type of cancer and location of tumour

2. the stage of the tumour (meaning if it has spread and how far)

3. the patient's age and general health

Treatments for cancer sometimes cause unwanted side effects such as hair loss, nausea, and weakness.

Destroying cancer cells brings about a remission, which is a period of time when the cancer is under control or when all the signs and symptoms of the cancer disappear. Complete remissions may continue for years and be considered cures. If the disease returns, another remission often can occur with further treatment.

POST-TEXT ASSINGMENTS

Exercise 6. Answer the questions:

1. What do we call a tumour?

2. Why are some neoplasms defined as "benign tumors"?

3. What are the main examples of benign tumors?

4. What inhibits benign tumors ability to behave in a malignant manner?

5. Depending on what may benign tumors cause specific symptoms?

6. What are the main pathological effects of some benign tumors?

7. What is the most effective approach in treating benign tumors?

8. What factors are called "risk factors for cancer"?

9. What treatments do the Cancer specialists primarily use to get rid of cancer?

10. What three things do the treatment choices for a person with cancer depend on?

Дата добавления: 2015-11-14