Hodgkin’s lymphoma – definition and most important information
Hodgkin's lymphoma (lymph node cancer) is one of the rare cancers.
A lymphoma arises from a malignant transformation of white blood cells called “lymphocytes”, which are part of the immune system. It usually develops in the lymph nodes under the arms, in the chest or neck, from where it can spread throughout the body. In Switzerland, about 270 people are diagnosed with Hodgkin’s lymphoma each year. Most affected are adolescents and young adults between the ages of 15 and 30, and slightly more often men than women. From the age of 55, the risk of developing the disease increases again. Hodgkin’s lymphoma has good prospects for long-term cure. Around 85 percent of those affected are still alive five years after diagnosis.
To understand what Hodgkin’s lymphoma is, it helps to know about the lymph system (also known as the lymphatic system).
The lymph system is part of the immune system, which helps fight infections and some other diseases. It runs through the entire body and consists of a network of lymphatic vessels, lymph nodes and lymphatic organs. The lymph nodes consist of certain types of lymphocytes.
There are 2 main types of lymphocytes:
- B lymphocytes (B cells): B cells make proteins called antibodies to help protect the body from germs like for instance bacteria and viruses.
- T lymphocytes (T cells): There are many types of T cells. Some T cells destroy germs or abnormal cells in the body. Other T cells help boost or slow the activity of other immune system cells.
Hodgkin’s lymphoma usually starts in B lymphocytes.
Hodgkin’s lymphoma – definition and most common forms
Hodgkin’s lymphoma is named after the British physician Thomas Hodgkin (1798-1866), who first described the disease in 1832. Around 95 percent of all cases are classic Hodgkin’s lymphoma (cHL). The cancer cells in this form are usually an abnormal type of B lymphocyte and are called Reed-Sternberg cells.
Classic Hodgkin’s lymphoma has 4 subtypes:
- Nodular sclerosis Hodgkin’s lymphoma, which generally begins in the lymph nodes of the neck and chest.
- Mixed-cell Hodgkin’s lymphoma, which is seen mostly in people with HIV infection and most often occurs in the lymph nodes in the upper half of the body.
- Lymphocyte-rich Hodgkin’s lymphoma, which isn’t common. It usually occurs in the upper half of the body and is rarely found in more than a few lymph nodes.
- Lymphocyte-depleted Hodgkin’s lymphoma, which is seen mainly in older people and those with HIV infection. It is more aggressive than other types and is most often in lymph nodes in the abdomen and in the spleen, liver, and bone marrow.
Most affected individuals show an easily palpable and often painless swelling of one or more lymph nodes in the neck, under the arm, or groin. The affected area may become painful after drinking alcohol. It may enlarge over time, or new enlarged lymph nodes may appear nearby or in other parts of the body.
Still, Hodgkin’s lymphoma is not the most common cause of lymph node swelling. Most enlarged lymph nodes, especially in children, are caused by an infection. The affected lymph nodes usually hurt when they’re touched.
Other, so-called B symptoms, include:
- Fever (which can come and go over several weeks) without an infection
- Drenching night sweats
- Weight loss without trying (at least 10% of your body weight over 6 months)
Other possible symptoms of Hodgkin’s lymphoma include:
- Itching skin
- Feeling tired (fatigue)
- Loss of appetite
These symptoms can also have other, more harmless causes than cancer. However, they should always be checked by a doctor. The earlier a tumor is detected, the better the treatment options and chances of recovery.
Hodgkin’s lymphoma risk factors
The risk factors for developing Hodgkin’s lymphoma are still unclear today, and the presence of one or more risk factors does not mean that the disease will actually occur. Many people who develop Hodgkin lymphoma have few or no known risk factors.
Known risk factors include:
- chronic infection with the Epstein-Barr virus, which causes mononucleosis
- weakened immune system, for example in the case of HIV infection
- familial predisposition
Other possible risk factors are:
- Mononucleosis or infection with the hepatitis B virus.
- Autoimmune diseases, such as rheumatoid arthritis
- Tobacco use.
Prevention of Hodgkin’s lymphoma
Only a few of the risk factors for Hodgkin’s lymphoma can be influenced. Therefore, it is not possible to prevent most cases of the disease at this time.
One risk factor that can be influenced is smoking. Avoiding tobacco can minimize the risk of developing Hodgkin’s lymphoma.
After a Hodgkin’s lymphoma diagnosis, there is a good chance of long-term cure. Chemotherapy with or without radiation therapy is generally used to treat Hodgkin’s lymphoma. Possible options in case of recurrence of the disease or if the therapy does not work are stem cell transplantation, targeted therapy or immunotherapy.