Non-Hodgkin’s lymphoma (NHL) is a lymphatic system cancer. Tumors develop from lymphocytes, a type of white blood cell. NHL is more common than Hodgkin’s lymphoma.
Many types of cancers can spread to the lymph nodes. However, only cancers that start in the lymph tissue are considered lymphomas.
Physicians and researchers don’t know what causes NHL. It occurs when the body makes too many abnormal lymphocytes. These abnormal cells don’t die. They continue to grow and divide. This enlarges the lymph nodes.
There are two types of NHL.
B-cell lymphomas occur more often than T-cell lymphomas. The most common types of B-cell lymphoma are diffuse large B-cell lymphoma and follicular lymphoma. Less common types of B cell lymphoma include:
- extranodal marginal zone B-cell
- lymphoplasmacytic (a B-cell lymphoma also known as Waldenström's macroglobulinemia)
- mantle cell
- mediastinal large B-cell
- nodal marginal zone B-cell
- small lymphocytic
T-cell lymphomas are much less common than B-cell lymphomas. Types of T-cell lymphoma include:
- anaplastic large cell
- peripheral T-cell
Many people with NHL have no obvious risk factors. It is also possible to have multiple risk factors without getting NHL. Some factors that may increase NHL risk include:
- older age, most people are aged 60 or older when diagnosed
- using immunosuppressant drugs
- infection, particularly with HIV, Epstein-Barr virus, or Helicobacter pylori
- exposure to certain chemicals, such as weed and insect killers
NHL symptoms may include:
- abdominal pain or swelling
- chest pain
- difficulty breathing
- swollen lymph nodes
- night sweats
- weight loss
A number of tests can be used to diagnose NHL.
Physical exams can be used to check size and condition of lymph nodes. They can also find an enlarged liver or spleen.
Blood and urine tests can be used to rule out other causes of swollen lymph nodes. Swollen nodes are usually just a sign of infection.
Imaging tests, such as X-rays, CT scans, MRIs, and PET scans, can be used to look for tumors. They can stage the cancer. They can also detect if the brain or spinal cord is involved.
Biopsy can remove a portion of the lymph node for testing. This can definitively identify NHL. A bone marrow biopsy can determine if the disease has spread.
Treatment depends on the age, type and stage of NHL.
Immediate treatment isn’t always necessary. Doctors may just monitor slow-growing NHL that doesn’t cause symptoms. Treatment can wait until the disease progresses.
More aggressive forms of NHL can be treated in several ways.
Chemotherapy can be given orally or by injection. It kills cancer cells. Chemotherapy may be used alone or with other treatments.
Radiation uses high-powered beams of energy to kill cancer cells and eradicate tumors. Radiation can be used alone or with other treatments.
Stem cell transplants allow doctors to use higher doses of chemotherapy. This treatment kills stem cells as well as cancer cells. Then a transplant is used to return healthy cells to the body. Transplants can be done with either the patient’s own cells or donor cells. For a patient’s cells to be used, they must be harvested in advance and frozen.
Medications can be used in to enhance the immune system. They can also be used to deliver radioactive isotopes that bind to cancerous cells.
Survival rates for NHL vary. Prognosis depends on age, overall health, the type of NHL, and how soon it is discovered. People with slower growing cancers can live a long time.
Sometimes NHL is not found until it is in the advanced stages. While aggressive forms of NHL can be treated, late diagnosis can cause problems. The cancer may be fatal before treatment has time to take effect.
Overall, the five-year survival rate for NHL is 63 percent. The 10-year survival rate is around 51 percent.
There is no known way to prevent NHL. However, it may be possible to reduce your risk for the disease by avoiding known risk factors such as obesity and HIV.