The lymphatic system.
Hodgkin's disease is a rare type of cancer characterized by painless enlargement of the lymph nodes, lymphatic tissue, and spleen, with subsequent spread to other areas. Fever is a common symptom of Hodgkin's disease and weight loss, anemia, loss of appetite, and night sweats may occur. The condition is named after the pathologist Thomas Hodgkin (1798-1866), who first described it. Hodgkin's disease is much more common in men. Treatment varies with the stage reached by the disease but in general consists of radiotherapy, surgery, chemotherapy, or a combination of these. Caught in the early stages it is potentially curable.
Hodgkin's disease is one of a group of cancers called lymphomas. Lymphoma is a general term for cancers that develop in the lymphatic system. Hodgkin's disease, an uncommon lymphoma, accounts for less than 1 percent of all cases of cancer in this country. Other cancers of the lymphatic system are called non-Hodgkin's lymphomas.
The lymphatic system and Hodgkin's disease
The lymphatic system is part of the body's immune system. It helps the body fight disease and infection. The lymphatic system includes a network of thin lymphatic vessels that branch, like blood vessels, into tissues throughout the body. Lymphatic vessels carry lymph, a colorless, watery fluid that contains infection-fighting cells called lymphocytes. Along this network of vessels are small organs called lymph nodes. Clusters of lymph nodes are found in the underarms, groin, neck, chest, and abdomen. Other parts of the lymphatic system are the spleen, thymus, tonsils, and bone marrow. Lymphatic tissue is also found in other parts of the body, including the stomach, intestines, and skin.
Cancer is a group of many related diseases that begin in cells, the body's basic unit of life. To understand Hodgkin's disease, it is helpful to know about normal cells and what happens when they become cancerous. The body is made up of many types of cells. Normally, cells grow and divide to produce more cells only when the body needs them. This orderly process helps keep the body healthy. Sometimes cells keep dividing when new cells are not needed, creating a mass of extra tissue. This mass is called a growth or tumor. Tumors can be either benign (not cancerous) or malignant (cancerous).
In Hodgkin's disease, cells in the lymphatic system become abnormal. They divide too rapidly and grow without any order or control. Because lymphatic tissue is present in many parts of the body, Hodgkin's disease can start almost anywhere. Hodgkin's disease may occur in a single lymph node, a group of lymph nodes, or, sometimes, in other parts of the lymphatic system such as the bone marrow and spleen. This type of cancer tends to spread in a fairly orderly way from one group of lymph nodes to the next group. For example, Hodgkin's disease that arises in the lymph nodes in the neck spreads first to the nodes above the collarbones, and then to the lymph nodes under the arms and within the chest. Eventually, it can spread to almost any other part of the body.
Who is at risk from Hodgkin's disease?
At this time, the cause or causes of Hodgkin's disease are not known, and doctors can seldom explain why one person gets this disease and another does not. By studying patterns of cancer in the population, researchers have found certain risk factors that are more common in people who get Hodgkin's disease than in those who do not. However, most people with these risk factors do not get Hodgkin's disease, and many who do get this disease have none of the known risk factors.
The following are some of the risk factors associated with this disease:
People who are concerned about the chance of developing Hodgkin's disease should talk with their doctor about the disease, the symptoms to watch for, and an appropriate schedule for checkups. The doctor's advice will be based on the person's age, medical history, and other factors.
What are the symptoms of Hodgkin's disease?Symptoms of Hodgkin's disease may include the following:
When symptoms like these occur, they are not sure signs of Hodgkin's disease. In most cases, they are actually caused by other, less serious conditions, such as the flu. When symptoms like these persist, however, it is important to see a doctor so that any illness can be diagnosed and treated. Only a doctor can make a diagnosis of Hodgkin's disease. Do not wait to feel pain; early Hodgkin's disease may not cause pain.
How is Hodgkin's disease diagnosed?
If Hodgkin's disease is suspected, the doctor asks about the person's medical history and performs a physical exam to check general signs of health. The exam includes feeling to see if the lymph nodes in the neck, underarm, or groin are enlarged. The doctor may order blood tests.
The doctor may also order tests that produce pictures of the inside of the body. These may include:
The diagnosis depends on a biopsy. A surgeon removes a sample of lymphatic tissue (part or all of a lymph node) so that a pathologist can examine it under a microscope to check for cancer cells. Other tissues may be sampled as well. The pathologist studies the tissue and checks for Reed-Sternberg cells, large abnormal cells that are usually found with Hodgkin's disease.
A patient who needs a biopsy may want to ask the doctor some of the following questions:
If the biopsy reveals Hodgkin's disease, the doctor needs to learn the stage, or extent, of the disease. Staging is a careful attempt to find out whether the cancer has spread and, if so, what parts of the body are affected. Treatment decisions depend on these findings.
The doctor considers the following to determine the stage of Hodgkin's disease:
In staging, the doctor may use some of the same tests used for the diagnosis of Hodgkin's disease. Other staging procedures may include additional biopsies of lymph nodes, the liver, bone marrow, or other tissue. A bone marrow biopsy involves removing a sample of bone marrow through a needle inserted into the hip or another large bone. Rarely, an operation called a laparotomy may be performed. During this operation, a surgeon makes an incision through the wall of the abdomen and removes samples of tissue. A pathologist examines tissue samples under a microscope to check for cancer cells.