What is Hodgkin lymphoma?
The lymphatic system is an important part of the immune system, which helps your body fight infection and disease. The lymphatic system is made up of lymph, lymph vessels, lymph nodes and lymphatic organs throughout the body. HL can start anywhere in the lymphatic system. It usually starts in a group of lymph nodes in one part of the body, most often in the chest, in the neck or under the arms.
There are 2 types of lymphocytes – B cells and T cells. HL usually starts in abnormal B cells, called Hodgkin and Reed-Sternberg (HRS) cells.
Hodgkin lymphoma is divided into 2 main forms based on if there are HRS cells. Classical HL has many HRS cells, but nodular lymphocyte-predominant HL does not have HRS cells.
Sometimes HL can cause generalized symptoms, which means they affect the whole body. These are called B symptoms or systemic symptoms. The symptoms are unexplained fever, night sweats and weight loss. Whether you have any B symptoms can help predict the outcome of the disease. If you have no B symptoms, there is a better outlook.
Classical HL is the most common type of HL (also sometimes simply called HL). About 95% of all HLs are classical HL. Classical HL has HRS cells present. Classical HL is divided into 4 subtypes.
Nodular sclerosis HL (NSHL) is the most common type of HL (about 60% to 70% of all cases). It is most often seen in teens and young adults 15 to 34 years of age. NSHL usually starts in lymph nodes of the deep tissue in the centre of the chest (called the mediastinum) or neck. It causes B symptoms in about 40% of people.
Mixed cellularity HL (MCHL) is the second most common type of HL (about 25% of all cases). It is most often seen in children and in adults 55 to 74 years of age. MCHL is more common in men. It is the type of HL that most often develops in people with HIV. MCHL usually develops in the upper half of the body and often affects lymph nodes in the abdomen and spleen. It usually causes B symptoms.
Lymphocyte-rich classical HL (LRHL) accounts for about 4% of all cases. It usually develops in lymph nodes in the neck, in the armpits and above the collarbone. LRHL rarely affects more than a few lymph nodes. It doesn’t usually cause B symptoms.
Lymphocyte-depleted HL (LDHL) is the least common type of HL (only about 1% of all cases). It may be seen in people with HIV. LDHL usually affects lymph nodes in the chest, abdomen, spleen, liver and bone marrow. Most people with LDHL have B symptoms.
Find out more about treatments for classical Hodgkin lymphoma.
Nodular lymphocyte-predominant HL
Nodular lymphocyte-predominant HL (NLPHL) accounts for about 5% of all HL cases. This type of HL does not have HRS cells. But it does have abnormal cells called LP cells, which may also be called popcorn cells because of how they look when viewed under a microscope.
NLPHL is most common in adults 30 to 50 years of age. It is more common in men. It usually starts in lymph nodes in the neck, underarm or groin. It is usually slow growing (indolent) and diagnosed at an early stage. Most people don’t have symptoms other than enlarged lymph nodes. B symptoms are rare.
Find out more about treatments for nodular lymphocyte-predominant HL.
The other main form of cancer of the lymphatic system is non-Hodgkin lymphoma (NHL). The abnormal B cells of Hodgkin lymphoma look and behave differently from non-Hodgkin lymphoma cells. Hodgkin lymphomas and non-Hodgkin lymphomas are treated differently.
A type of white blood cell that fights viruses, bacteria, foreign substances or abnormal cells (including cancer cells).
The 3 types of lymphocytes are B cells, T cells and natural killer (NK) cells.