What is Lymphoma ?

Lymphomas are cancers that affect the lymphatic system and arise when developing lymphocytes (a type of white blood cell) undergo a malignant change and multiply in an uncontrolled way. In America in 2010 there were 153,535 people living with or in remission (that is no sign of the disease) from lymphoma
Increasing numbers of abnormal lymphocytes, called lymphoma cells, accumulate and form collections of cancer cells (tumours) in lymph nodes (glands) and other parts of the body. Over time, lymphoma cells replace normal lymphocytes, weakening the immune system's ability to fight infection.
Lymphomas can develop at any age but the majority of lymphomas occur in two peaks the first in young adulthood (age 15-35) and the second peak in people over the age of 55 years. The peak age for diagnosis of Hodgkin lymphoma is between 15 and 30 years.
Over all lymphoma is more common in males. The annual incidence of Hodgkin’s lymphoma is about 1 in 25,000 people and the disease accounts for slightly less than 1% of all cancers worldwide.

Causes of Lymphoma

The incidence of lymphoma is increasing every year. In most cases we don't know what causes lymphomas, but there are likely to be a number of factors involved. Like all cancers, lymphomas may result from damage to (or mutation of) special proteins called genes that control the growth and division of cells. Like other cancers it is not infectious, and it is not inherited.
We know that people with a weakened immune system (either due to an immunodeficiency disease or drugs that suppress the function of the immune system) are at an increased risk of developing lymphomas. Patients with a history of infectious monoucleosis due to Epstein-Barr virus may have an increased risk of Hodgkin’s lymphoma. Certain types of viral infections may also play a role, especially in people with a weakened immune system.
The disease occurrence shows two peaks: the first in young adulthood (age 15–35) and the second in those over 55 years old.

Surviving Lymphoma

The 10-year overall survival rate is more than 90% no matter what stage your disease is caught at. Since many patients are young, they often live 40 years or more after treatment. However, few studies follow patients as long as 25 years, and those studies are of older treatments with more life-threatening adverse effects, so it is impossible to predict long-term outcomes of newer, less harmful treatments. Radiation treatments, and some chemotherapy drugs, pose a risk of causing secondary cancers, heart disease, and lung disease 40 or more years later. Modern treatments greatly minimize the chances of these late effects. Patients with a history of infectious mononucleosis due to Epstein-Barr virus may have an increased risk of HL.

Symptoms of Lymphoma

Lymphomas commonly present as a firm, painless swelling of a lymph node (swollen glands), usually in the neck, under the arms or in the groin.

Other symptoms may include:

Recurrent fevers or high temperatures which occur for no apparent reason.

Excessive sweating at night

Unintentional weight loss

Persistent lack of energy

Generalised itching

Lymphoma may develop in the lymph nodes in deeper parts of the body, like those found in the abdomen (causing bloating), or in the chest (causing coughing, discomfort in the chest and difficulty breathing). Occasionally the disease starts in other sites such as the bone or the skin and it would then be associated with symptoms for that site such as bone pain or skin lumps or rashes.

Other less common symptoms:

Hepatomegaly: enlargement of the liver, due to liver involvement, is present in about 5% of cases.

Hepatosplenomegaly: the enlargement of both the liver and spleen caused by the disease.

Pain following alcohol consumption: classically, involved nodes are painful after alcohol consumption, though this phenomenon is very uncommon.

Back pain: nonspecific back pain (pain that cannot be localized or its cause determined by examination or scanning techniques) has been reported in some cases of Hodgkin's lymphoma. The lower back is most often affected.

Red-coloured patches on the skin, easy bleeding and petechiae due to low platelet count (as a result of bone marrow infiltration, increased trapping in the spleen etc. – i.e. decreased production, increased removal)

In some cases, people don't have any troubling symptoms and the disease is picked up during a routine chest x-ray.

Diagnosing Lymphoma

If your doctor suspects any form of lymphoma you will be referred to a hospital for blood tests and a chest x-ray. Subsequent to this it may be necessary to remove a lymph node and examine it under a microscope. This is called a lymph node biopsy; the examination includes tests called “immunophenotying” and “cytognetic analysis” This procedure may be carried out using a local or a general anesthetic. This is a simple procedure and you would be able to go home afterwards.
It is important that all patients receive an accurate diagnosis, but this may be difficult. especially with Non-Hodgkin’s lymphoma since the subtypes of NHL can be confused with each other. It requires an experienced hematopthologist (a doctor who specializes in interpreting and diagnosing the physical changes caused by diseases of the blood and marrow) to analyze the biopsy slides. Another opinion by a second hematopathologist may be asked for.
NHL involving sites outside of the lymph nodes most commonly occurs with lymph node involvement. When lymphoma is detected exclusively outside of the lymph nodes, it is called “primary extranodal lymphoma”, and the biopsy specimen is taken from the involved tissue, such as the lung or bone.
The hematopathologist prepares a slide from the biopsy specimen by placing the tissue in a preservative and staining it with dyes. The slide is examined under a microscope, and cells with lymph node changes that are characteristic of specific Hodgkin’s or NHL subtypes are identified. The distinctive patterns of these cells help the pathologist to categorize the patient’s lymphoma into one of many subtypes.

Examining Lymph Node Biopsy Samples. Several methods may be used, including

Immunophenotyping, a process that allows the pathologist to study the cells obtained at the time of tissue biopsy. Immunophenotyping can provide additional evidence that these cells are lymphoma cells and, further, whether they are B cells, T cells or NK cells. The cell type can also be determined by other techniques, such as

Cytogenetic analysis, in which cells are studied to see if chromosomal abnormalities are present. Chromosomal abnormalities can be important in identifying specific subtypes of NHL and choosing the most effective treatment approach.

Gene expression profiling and microarray analysis, which identify cancer subtypes and risk factors. These tests help predict treatment response and which patients may be at increased risk for relapsed disease. For example, gene expression profiling is used to identify different forms of diffuse large B-cell lymphoma.

The level of expression of specific proteins made by genes may be a predictor of how well a patient will respond to treatment with specific therapies. These levels can be assessed by polymerase chain reaction (PCR), a technique to expand trace amounts of DNA or RNA so that the specific type of the DNA or RNA can be determined. This method has become useful in detecting a very low concentration of residual lymphoma cells—too few to be seen using a microscope. The technique can detect the presence of one lymphoma cell among 500,000 to one million nonlymphoma cells. The use of PCR requires a specific DNA abnormality or marker, such as an oncogene, in the lymphoma cells.

The Lymphatic System

The lymphatic system is one of the body’s systems of defense against infection. It is made up of a network of tiny vessels, like blood vessels, which carry a clear fluid called lymph. This lymphatic fluid contains infection fighting cells called lymphocytes. The marrow produces three main types of lymphocytes

B lymphocytes (B cells), which make antibodies in response to foreign antigens, especially microbes.

T Lymphocytes (T cells), which develop in the thymus. The T lymphocytes have several functions, including assisting B lymphocytes to make antibodies against invading bacteria, viruses or other microbes. The antibody attaches to the microbe, making it possible for other white cells to recognize the antibody and ingest it into the cell along with its attached microbe. The white cell then kills and digests the microbe.

Natural killer (NK) cells, which attack virus infected cells without requiring antibody or other mediation. T cells and NK cells have other functions as well and are important elements in research efforts to design immunotherapy’s to treat lymphoma and other cancers.

Along this network are hundreds of small bean shaped glands called lymph nodes. Their job is to filter the lymphatic fluid for foreign particles as it passes through. They also allow the lymphocytes to interact so that they can function to protect the body against infection.

Types of Lymphomas

There are many different types of lymphome which are bradly divided into two main groups, click on the headers below to view the full articles

1. Hodgkins Lymphoma

2. Non-Hodgkin Lymphomas NHL (or B-cell or T-cell lymphomas)