Cancers that present in the lymph nodes could have started in the lymph nodes or could have been spread from other parts of the body.
Cancer cells can break away from the primary site and travel through the bloodstream to reach distant organs. Similarly, the cancer cells may also gain access to the lymphatic system to circulate and reach other organs. As they travel through the lymphatic system, they may deposit in the lymph nodes. Most cancer cells are killed or destroyed before they reach other parts of the body, but if one or two cancer cells are able to evade the body’s immune system, they can settle in a new area and begin to grow and replicate.
Metastasis mostly affects lymph nodes that are near the tumour itself.
Lymphomas – primary cancers of the lymph nodes
Lymphomas begin when the white blood cells (lymphocytes) develop genetic mutations. The mutations cause the cell to multiply in an uncontrolled rate. Mutations also allow the abnormal cells to escape death, causing the proliferation and collection of diseased white blood cells in the lymph nodes and other organs, forming tumours.
Besides the lymph nodes and vessels, the lymphatic system includes other organs such as the thymus, spleen and bone marrow. Lymphomas can also affect these organs, and also other organs throughout the body.
Lymphomas are the third most common cancer among young adults and children in Singapore. Early detection and diagnosis is important to increase the chances of cure.
The most common types of lymphomas are:
- Hodgkin’s Lymphoma
- More common in young adults aged between 15 to 30 years
- Includes classical Hodgkin’s Lymphoma (more common) as well as nodular lymphocyte-predominant Hodgkin’s lymphoma
- Non-Hodgkin’s Lymphoma
- More common in older people and more common than Hodgkin’s Lymphoma
- Includes diffuse large B-cell lymphoma and follicular lymphoma
Lymphomas are also associated with reduced immunity, due to increasing age or other causes. Such causes include reduced immunity from birth, immunosuppressant drugs or infection by HIV. Treatment and prognosis depends on the type of lymphoma a patient has.