In primary lymph node cancer or lymphoma, the cells of the lymph nodes (lymphocytes) become cancerous resulting in abnormal and excessive proliferation or growth of the tissues and cells of the lymph nodes. This causes enlargement of lymph nodes in various parts of the body and these swollen lymph nodes are most often detected in the armpit, neck or groin as painless, hard swellings.
Lymphomas are usually restricted within the lymph nodes or other lymphatic tissue but may sometimes spread to other types of tissues in the body, where it is known as extranodal disease.
There are two types of lymphomas – Hodgkin’s lymphoma and non-Hodgkin lymphomas. The latter, non-Hodgkin lymphomas, includes all other lymphomas which are not Hodgkin’s lymphoma. These are further divided into five subtypes of Hodgkin’s lymphoma and about 30 subtypes of non-Hodgkin lymphoma based upon their microscopic appearance, genetic arrangement or extent of the disease process.
Hodgkin’s lymphoma and non-Hodgkin lymphoma may present with similar symptoms but microscopically they are two different entities.
Difference between Hodgkin’s Lymphoma (HL) and Non-Hodgkin’s Lymphoma (NHL)
- Hodgkin’s lymphoma is more likely to occur in the age group of 15 to 35 years. Non-Hodgkin lymphomas may occur in any age but the incidence increases in the elderly, especially after the age of 60.
- Hodgkin’s lymphoma is a rare form of lymphoma while non-Hodgkin lymphoma is a common type of lymph node cancer.
- Hodgkin’s lymphoma is usually localized to a group of lymph nodes and spreads in an orderly fashion from one lymph node to the next. Non-Hodgkin lymphomas involves a more widespread region.
- Upon microscopic investigation, the presence Reed-Sternberg cells froma lymph node biopsy is conclusive evidence of Hodgkin’s lymphoma.
Signs and Symptoms of Lymph Node Cancer
The first symptom of lymphoma may be a painless lymph node swelling of the armpit, neck or groin. Other signs and symptoms may be non-specific. These include :
- Abdominal pain due to enlargement of the spleen.
- Pressure symptoms caused by the enlarged lymph node, such as edema or swelling of the arms or legs (due to pressure on a vein or lymphatic vessel), tingling and numbness or pain (due to pressure on a nerve).
- Unexplained and often rapid weight loss.
- Excessive fatigue.
- Loss of appetite.
- Fever with chills.
- Excessive night sweats.
- Itchy skin.
- Difficulty breathing.
- Persistent coughing.
- Chest pain.
Due to the non-specific nature of most of these symptoms, it is important to first exclude other common causes. However if the symptoms persist for a long period or recur frequently, it is advisable to consult with a doctor.
Risks and Causes of Lymphomas
The exact cause of a lymphoma is not known but certain risk factors have been associated with the disease.
- Age. Lymphomas can occur at any age, both in children and adults, but those between the age group of 15 to 35 and above 55 years of age are said to be at increased risk of developing Hodgkin’s lymphoma. Non-Hodgkin lymphoma is more common in the older age group.
- Gender. Males are at slightly higher risk than females.
- Family history of the disease.
- Epstein-Barr virus (EBV), which causes infectious mononucleosis, has been implicated in the development of Hodgkin’s lymphoma. Previous infection with this virus is cnsidered as a risk factor for developing Hodgkin’s lymphoma. In Africa, EBV has been linked with Burkitt’s lymphoma which is a fast-growing form of non-Hodgkin lymphoma.
- Helicobacter pylori infection, which causes stomach ulcers, increases the chance of developing stomach lymphoma.
- Infection with the Hepatitis B or C virus.
- Infection with human T-lymphocytic virus type 1 (HTLV-1).
- Immuno-compromised people, such as those with HIV/AIDS, various types of autoimmune diseases, or patients undergoing an organ transplant who require immuno-suppressive therapy.
- Evidence suggests that long term use of certain types of dark hair dye may increase the risk of developing non-Hodgkin lymphoma.
- Toxins – long term exposure to certain pesticides, herbicides, and benzene.
- Exposure to high levels of radiation increases risk of developing non-Hodgkin lymphoma.
- Research shows that smoking may be considered to be a risk factor in the development of Hodgkin’s lymphoma, especially in those with Epstein-Barr virus infection.
- Based on prevalence of lymphomas, there appears to be a higher incidence of Hodgkin’s lymphoma in the United States, Canada and Europe while the incidence is much lower in Asian countries. There also appears to be a higher incidence of Hodgkin’s lymphoma among higher socioeconomic groups. Both instances could be attributed to better access to specialist health care services in the respective countries and socioeconomic groups.
Diagnosis and Investigations
Often lymphomas are detected on routine examinations. At times, the only complaint may be a persistent or recurrent swelling of the armpit, groin or neck lymph nodes with no other signs and symptoms. In other instances, there may only be flu like symptoms or other non-specific symptoms.
If lymphoma is suspected, certain tests will need to be done to confirm the diagnosis.
- Blood tests to search for any indication of cancer.
- Lymph node biopsy will confirm the diagnosis of lymphoma and also the type of lymphoma.
- X-rays to show the location of enlarged lymph nodes.
- Ultrasound will also detect lymph node enlargement.
- MRI or CT scan provides detailed images of lymph nodes and may be done to detect enlarged lymph nodes throughout the body.
- Gallium scan where radioactive gallium is injected into the body tends to aggregate within the lymphoma, which can then be seen on a scan.
- Positron-emission tomographic (PET) scan is a newer method of scanning after injection of a radioactive substance, which indicates the site of a lymphoma.
- Bone marrow biopsy is done to assess whether the bone marrow has been affected by the lymphoma.
- Lumbar puncture or a spinal tap may be done to collect a sample of cerebrospinal fluid (CSF) to determine whether the lymphoma has affected the central nervous system.
Staging and grading of lymphomas are done based on their size, spread of the disease and other associated signs and symptoms. This helps to determine the treatment plan and also gives an indication about the outcome of the disease.
Treatment of Lymphomas
Once diagnosed, the treatment plan followed will depend upon the type of lymphoma, stage of the disease, age and general health of the patient as well as other factors like pregnancy. Previous treatment(s) for a lymphoma will also be taken into account.
- Watch and wait (watchful waiting) is just observation and careful assessment which may be initially advisable in slow-growing or recurrent lymphomas. If this option is followed, then treatment is undertaken only if there is rapid growth of the lymphoma or if there is development of any other signs and symptoms.
- Radiation therapy is where high-energy rays are used to destroy the cancer cells in the affected lymph nodes. Radiation is normally the first line of therapy for early stage lymphomas. Sometimes a combination of radiation therapy and chemotherapy may be more effective. Certain undesirable side effects of this form of therapy includes nausea, vomiting, diarrhea, loss of appetite, fatigue, dermatological (skin) problems, hair loss, and suppression of the immune system as well as blood count, thus making the person more susceptible to infections.
- Chemotherapy involves is the use of chemical agents (drug) to destroy cancer cells. For late-stage lymphomas, chemotherapy is the first line of treatment and it may be combined with radiation therapy for treating large tumors. A combination of drugs is usually more effective but the side effects are similar to those encountered with radiation therapy.
- Immunotherapy or biological therapy is based on using the body’s natural immune mechanism hence undesirable side effects are eliminated or minimized. There are several types of therapies which fall under this group, such as monoclonal antibodies, cytokines and vaccines.
- Bone marrow or stem cell transplantation my be considered for recurrent lymphomas.
Primary Lymph Node Cancer Prognosis
The prognosis depends upon the absence or presence of certain risk factors. The higher the number of risk factors, the less favorable the outcome. The treatment implemented also determines the outcome especially if it is prompt treatment in early detection of a lymphoma.
For Hodgkin’s lymphoma the risk factors according to the International Prognostic Index are :
- Age above 45 years.
- Gender – male.
- Stage of disease – stage IV.
- Blood albumin level less than 4.0 g/dL
- Hemoglobin less than 10.5 g/dL
- High WBC (white blood cell) count – more than 15000/mL.
- Low lymphocyte count – less than 600/mL or less than 8% of total WBC count.
For non-Hodgkin’s lymphoma the risk factors based on the International Prognostic Index are :
- Age above 60 years.
- Stage of disease – stage III or IV.
- More than one extranodal site.
- High levels of LDH (lactate dehydrogenase) in the blood.
- General health of the patient.
The outlook for Hodgkin’s lymphoma is usually better although the availability of new therapies for non-Hodgkin lymphoma has definitely improved the 5-year survival rate.
In some patients, the cancer may go into remission after treatment. This means that although the cancer is not cured totally, it has become dormant with no detectable cancer cells in the body or any other signs and symptoms of the disease. Remission may continue for months or years but it is possible that the cancer may recur again.
After completing a course of therapy, it is important to maintain regular follow-up consultations with your doctor so that any recurrence of cancer can be detected early and treated promptly.