Overview
Non-Hodgkin lymphoma is a type of cancer that affects the lymphatic system. The lymphatic system is made up of organs, glands, tubelike vessels and clusters of cells called lymph nodes. It's part of the body's germ-fighting immune system.
Non-Hodgkin lymphoma happens when germ-fighting cells in the lymphatic system grow out of control. The cells can form growths, called tumors, throughout the body.
Non-Hodgkin lymphoma is a broad group of lymphomas. There are many subtypes in this group. Diffuse large B-cell lymphoma and follicular lymphoma are among the most common subtypes. The other broad group of lymphoma is Hodgkin lymphoma.
Advances in diagnosis and treatment of non-Hodgkin lymphoma have helped improve the prognosis for people with this condition.
Symptoms
Signs and symptoms of non-Hodgkin lymphoma may include:
- Swollen lymph nodes in the neck, armpits or groin.
- Belly pain or swelling.
- Chest pain, coughing or trouble breathing.
- Feeling very tired.
- Fever.
- Night sweats.
- Weight loss without trying.
When to see a doctor
Make an appointment with your doctor if you have any persistent signs and symptoms that worry you.
Causes
The cause of non-Hodgkin lymphoma often isn't known. This cancer starts when germ-fighting white blood cells called lymphocytes develop changes in their DNA. A cell's DNA holds the instructions that tell the cell what to do.
DNA gives healthy cells instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time. In cancer cells, the DNA changes give other instructions. The DNA changes tell the cancer cells to make more cells quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells.
In non-Hodgkin lymphoma, the cancer cells often build up in the lymph nodes. They also can build up in other parts of the lymphatic system.
Non-Hodgkin lymphoma can affect the:
- Lymph nodes.
- Lymph vessels.
- Adenoids.
- Tonsils.
- Spleen.
- Thymus.
- Bone marrow.
- Rarely, parts of the body that aren't part of the lymphatic system.
Non-Hodgkin lymphoma types
Non-Hodgkin lymphoma most often begins in the:
- B cells. B cells are a type of lymphocyte that fights infection. B cells make antibodies against foreign invaders. Most non-Hodgkin lymphoma arises from B cells. Subtypes of non-Hodgkin lymphoma that involve B cells include diffuse large B-cell lymphoma, follicular lymphoma, mantle cell lymphoma and Burkitt's lymphoma.
- T cells. T cells are a type of lymphocyte that kills foreign invaders directly. Non-Hodgkin lymphoma happens much less often in T cells. Subtypes of non-Hodgkin lymphoma that involve T cells include peripheral T-cell lymphoma and cutaneous T-cell lymphoma.
Treatment depends on whether non-Hodgkin lymphoma arises from B cells or T cells.
Risk factors
Factors that may raise the risk of non-Hodgkin lymphoma include:
- Medicines that lower the immune response. Taking medicines that manage the immune system after an organ transplant might raise the risk of non-Hodgkin lymphoma.
- Infection with certain viruses and bacteria. Certain infections seem to raise the risk of non-Hodgkin lymphoma. Viruses linked to this type of cancer include HIV and Epstein-Barr virus. Bacteria linked to non-Hodgkin lymphoma include the stomach ulcer-causing bacterium Helicobacter pylori.
- Chemicals. Certain chemicals, such as those used to kill insects and weeds, may raise the risk of non-Hodgkin lymphoma. More research is needed to find the possible link between pesticides and non-Hodgkin lymphoma.
- Older age. Non-Hodgkin lymphoma can happen at any age. But it's most common in people 60 or older.
There's no way to prevent non-Hodgkin lymphoma.