What is lymphoma?
Lymphoma is cancer of the lymphatic system, and is the sixth most common form of cancer in Australia. The lymphatic system is part of the immune system and consists of lymph nodes (sometimes referred to as lymph glands) that are connected by small vessels known as lymphatics. The spleen and bone marrow are also considered to be part of the lymphatic system.
In this type of cancer, cells in the lymphatic system called lymphocytes (a type of white blood cell) become abnormal and divide and grow uncontrollably. This uncontrolled growth leads to the development of cancerous tumours in the lymph nodes and other parts of the lymphatic system. It is also possible for lymphoma to involve organs outside of the lymphatic system.
There are 2 main types of lymphoma: Hodgkin (or Hodgkin’s) lymphoma and non-Hodgkin (or non-Hodgkin’s) lymphoma.
Hodgkin lymphoma (also known as Hodgkin’s lymphoma or Hodgkin’s disease) tends to affect younger people, most commonly those who are in their mid-teens to early 30s, and also people over 55 years. Although Hodgkin lymphoma is a serious disease, many people are cured with treatment — after 5 years, the survival rate is over 87 per cent.
This form of lymphoma is more common than Hodgkin’s disease. In fact, over 90 per cent of all people with lymphoma have the non-Hodgkin form of the disease. The risk of developing non-Hodgkin lymphoma increases with age, and the disease is most common in people aged over 60 years. While the number of new cases of non-Hodgkin lymphoma appears to be increasing over time, the survival rate has improved, and is currently about 71 per cent after 5 years.
The symptoms of Hodgkin and non-Hodgkin lymphoma are similar. Usually the first symptom is a swelling or a lump in the lymph nodes. Lymph node swellings are most often noticed in the neck, under the armpits, just above the collarbone, or in the groin area. People with lymphoma may also experience any or all of the following:
- sweating, especially at night;
- reduced appetite;
- weight loss;
- pain in the chest or abdomen;
- persistent cough;
- generalised itch; and
- persistent tiredness.
The exact cause of lymphoma is not known. As with other cancers, the combination of genetic and environmental factors may play a role in its development. Certain viral infections, including HIV, can increase your risk of particular types of lymphoma. People whose immune systems are suppressed may have a higher risk of developing lymphoma.
To make a diagnosis of lymphoma, your doctor will need to take a biopsy of the lump or swelling of the lymph nodes. A biopsy involves taking a sample of tissue which can then be examined under the microscope.
If you have lymphoma, your doctor will determine the most appropriate treatment for you based on several factors. These include the type of lymphoma you have, how far the disease has spread, your age and your overall health. Treatment usually involves chemotherapy, radiotherapy or both. These treatments are aimed at destroying as many cancerous cells as possible to achieve cure or remission (long-term control of the disease).
Sometimes, a stem cell or bone marrow transplant may be needed. This type of treatment may be required if the disease does not respond to treatment or recurs after initial treatment, or there is a high likelihood of recurrence.
Immunotherapy, or biological therapy, is also available to treat certain types of non-Hodgkin lymphoma. This treatment involves the use of medicines that contain laboratory-produced antibodies (monoclonal antibodies), such as rituximab. These antibodies help the immune system to recognise and kill the lymphoma cells.
Interferon is another form of biological therapy that may be used to treat some types of non-Hodgkin lymphoma.