HODGKIN'S DISEASE
DEFINITION
Hodgkin's disease is a cancer of the lymphatic (pronounced lim-FAT-ic) system. The lymphatic system consists of blood vessels, tissues, and other structures that carry lymph (pronounced limf) through the body. Lymph is a bloodlike fluid that carries substances from cells to blood vessels.
A variety of cancers can affect lymph tissue. These cancers are called lymphomas. Hodgkin's disease is one kind of lymphoma. It is also called Hodgkin's lymphoma. The cause of Hodgkin's disease is unknown. Many experts believe that genetic and environmental factors work together to cause the disease.
DESCRIPTION
Hodgkin's lymphoma can occur at any age. It is most common, however, in people between the ages of fifteen and thirty-four and after the age of sixty. An understanding of the lymphatic system is necessary in order to understand the nature of Hodgkin's lymphoma.
The Lymphatic System
Lymph is usually a clear, colorless liquid that forms in the space between cells throughout the body. It consists of waste products from those cells.
Lymph is drained into tiny vessels, like blood vessels. These vessels form a network of tubes that eventually leads to large veins at the base of the neck and inside the abdomen. At various points in this network, lymph passes through small lumps of tissue known as lymph nodes.
Lymph nodes contain special kinds of cells that act as filters. These cells remove foreign substances, such as viruses, bacteria, and cancer cells, from lymph. For this reason, they are part of the body's immune system, protecting it from infection.
Hodgkin's Disease: Words to Know
- Biopsy:
- The removal of a small sample of tissue and its examination under a microscope for the purpose of diagnosing
- Chemotherapy:
- Treatment of a disease with certain chemicals or drugs that destroy cancer cells.
- Radiotherapy:
- Treatment of a disease using some form of radiation, such as X rays.
One kind of cell found in lymph is a white blood cell called a lymphocyte. The role of lymphocytes is to identify foreign bodies in lymph and to help eliminate those materials from the lymph.
Cancer of the Lymph System
Cancer is a condition in which cells grow out of control (see cancer entry). Cancer can appear in any part of the lymph system. Cells within a lymph node, for example, may begin to grow rapidly. They may take on unusual shapes and begin to spread throughout the body. Cancers that affect any part of the lymph system are known as lymphomas.
CAUSES
Hodgkin's lymphoma usually begins in a lymph node. The node enlarges and may or may not become painful. The cancer typically moves from one lymph node to another nearby lymph node. Eventually, cancer cells can be carried to other organs in the body, including the spleen, liver, and bone marrow.
SYMPTOMS
Some of the early symptoms of Hodgkin's lymphoma include fever, weight loss, heavy sweating at night, and itching. Some patients report that drinking alcoholic beverages may cause pain in the infected area.
As lymph nodes swell, they may push on other nearby structures. This pressure may also cause pain and other kinds of discomfort. For example, nerves may be pinched, causing pain and loss of muscular control. Pressure on the ureters, the tubes that carry urine from the kidneys to the bladder, can cause kidney failure. Pressure on veins in the face, neck, and legs can reduce blood flow and cause swelling in those areas. Pressure on the spinal cord can cause paralysis of the legs. Pressure on the upper respiratory (breathing) system can cause wheezing and shortness of breath. Abnormal tissue growth in the liver can cause an accumulation of toxins (poisons), resulting in jaundice. Jaundice is a yellowish discoloration of the skin and whites of the eyes. It is a common sign of liver disease.
As Hodgkin's disease worsens, the lymphatic system becomes less effective in fighting off infections. Patients with the disease are more likely to develop infections caused by bacteria, viruses, and other types of germs.
DIAGNOSIS
Diagnosis involves two steps. First, the doctor must identify Hodgkin's disease as the cause of the patient's symptoms. Second, the doctor must determine how far the disease has progressed.
Hodgkin's disease is usually diagnosed by means of a biopsy. A biopsy is a process in which a small sample of tissue is removed from the infected part
of the patient's body. In the case of Hodgkin's disease, the biopsy is usually done on a lymph node. The sample is then examined under a microscope. The presence of certain characteristic types of cells is evidence of a lymphoma.
Additional procedures are necessary to see how far the disease has spread. For example, a bone marrow biopsy may be conducted to see if the disease has spread to this part of the body. A computed tomography (CT) scan may be ordered to see if the disease has spread to the abdomen, chest, pelvis, and other parts of the body. A CT scan is a procedure by which X rays are directed at a patient's body from various angles and the set of photographs thus obtained assembled by a computer program. This procedure is sometimes called a computerized axial tomography (CAT) scan. A lymphangiogram can also be performed. A lymphangiogram is similar to an X ray of the lymphatic system. It indicates the parts of the system that have become cancerous.
Finding out how far the disease has spread is important because it determines the kind of treatment the patient should have. Most treatments have serious side effects. A doctor wants to use only enough of a treatment to kill the lymphoma, not enough to do other serious damage to the body.
TREATMENT
Two forms of treatment are used with Hodgkin's disease: chemotherapy and radiotherapy. Chemotherapy involves the use of drugs to kill cancer cells. Radiotherapy uses X rays or other forms of radiation to achieve the same result. Both methods of treatment work quite well with Hodgkin's lymphoma.
Unfortunately, both treatments also have unpleasant side effects. Chemotherapy can result in nausea, vomiting, hair loss, and an increased risk for infections. Radiotherapy can cause sore throat, difficulty in swallowing, diarrhea, and changes in growth patterns for children. Both forms of treatment, especially when they are used together, can cause sterility. Sterility is the loss of the ability to have children. Heart and lung damage are also possible side effects when the two treatments are used together.
One of the most serious problems in the treatment of Hodgkin's disease is the possibility of a secondary cancer. A secondary cancer is a new cancer that occurs elsewhere in the body after the Hodgkin's lymphoma has been cured. Secondary cancers can occur in blood, bone, the thyroid, or other parts of the body.
PROGNOSIS
The cure rate for Hodgkin's disease is among the highest for any form of cancer. Treatments seem to work best with children. About 75 percent of children treated for Hodgkin's disease are still alive twenty years after the original diagnosis. For adults with the most serious forms of the disease, the cure rate is still as high as 50 percent.
PREVENTION
There is no know method of preventing Hodgkin's disease.
FOR MORE INFORMATION
Books
Dollinger, Malin, et al. Everyone's Guide to Cancer Therapy. Kansas City, MO: Andrews McKeel Publishing, 1997.
Murphy, Gerald P., et al. Informed Decisions. New York: Viking Press, 1997.
Periodicals
Stoval, Ellen. "A Cancer Survivor Discusses Her Experiences." Washington Post (February 14, 1995): pp. WH15+.
Organizations
The Lymphoma Research Foundation of America, Inc. 8800 Venice Boulevard, Suite 207, Los Angeles, CA 90034. (310) 204–7040. http://www.lymphoma.org.
Web sites
"Ask NOAH About: Cancer." NOAH: New York Online Access to Health. [Online] http://www.noah.cuny.edu/cancer/cantypes.html#H (accessed on October 25, 1999).