Lymphoma is a type of cancer that affects the lymphatic system which consists of the lymph nodes, spleen, bone marrow, tonsils and thymus gland. Other organs in the body may be affected as well. Lymphoma occurs when there is out-of-control growth and multiplication of lymphocytes (infection-fighting white blood cells).
There are over 70 types of cancers that have been classified as Lymphoma, but doctors generally divide this type of cancer in these two main subtypes:
- Hodgkin’s Lymphoma
- Non-Hodgkin’s Lymphoma (NHL)
What is the lymphatic system?
The lymphatic system helps the body get rid of toxins and other waste products by transporting fluid, or lymph, that contains white blood cells, which are crucial in fighting infection, throughout the body.
Similar to the blood circulatory system, the lymphatic system is made up of lymphatic vessels that are attached to lymph nodes which is where lymph is filtered.
These are the main components that make up the lymphatic system:
Lymph nodes – lymph is filtered through the lymph nodes which also produces cells that make up the immune system. There are about 600 lymph nodes distributed all over the body and some of the more noted ones include those that are in the neck, groin and armpit. While there are single lymph nodes, others are connected in groups by lymph vessels and are known as chains.
Lymph – a watery, colourless liquid that is made up of excess fluid that has not been reabsorbed into the bloodstream. Lymph carries proteins, fats, nutrients, minerals, lymphocytes (white blood cells that fight infection), as well as damaged cells and cancer cells.
Lymphatic vessels – the lymphatic vessels make up a network of capillaries and tubes found throughout the body which moves lymph away from body tissues until they are finally reabsorbed back into the blood circulatory system.
Thymus – located above the heart and behind the breast bone, the thymus produces lymphocytes and is a key lymphoid organ of the immune system.
Spleen – an organ that primarily filters blood, the spleen is located in the upper left abdomen. It recycles red blood cells and holds a supply of platelets and white blood cells.
How does it work?
Plasma flows through the blood vessels daily, delivering oxygen and nutrients to body tissues and cells. As part of the blood circulatory system, waste is received from these body tissues and cells, and transported by veins, which carry deoxygenated blood, back to the heart.
However, not all the plasma that has been pumped out by the heart to the rest of the body is returned. Some of the blood carrying waste products and deoxygenated blood seeps through the thin blood capillaries and flows into body tissues. The role of the lymphatic system is to pick up this extra fluid and keep it moving until it goes back into the blood.
The causes of Lymphoma are still unknown. What doctors do know, however, is that it occurs when there is a genetic abnormally in the lymphocyte, a white blood cell that is crucial in fighting infection. This genetic abnormally causes the cell to quickly multiply and collect in the various lymph nodes in different parts of the body, leading to swelling of the lymph nodes, spleen and liver.
Lymphoma is the fifth and sixth most common cancer for males and females respectively in Singapore, with about 800 new cases in total diagnosed per year (Singapore Cancer Registry Annual Report 2018: Singapore Cancer Registry 50th Anniversary Monograph 1968-2017). Little is known about the causes of lymphoma. Almost all types of lymphoma contain mutations within the DNA, and risk factors include older age, exposure to certain chemicals, immune deficiency (due to immunosuppressive drugs, HIV/AIDS, or congenital immune deficiency), certain infections (H. pylori of the stomach and human T-lymphotropic virus), radiation exposure, and possibly some viruses such as Epstein-Barr virus and hepatitis C virus
Signs and Symptoms
Common signs and symptoms of lymphoma include enlarged lymph nodes, lethargy, fever, night sweats, poor appetite, weight loss, pain, profound fatigue, itching, and abnormal routine blood tests. Certain observations may raise the suspicion of lymphoma. The doctor or physician may feel enlarged lymph nodes during a routine clinical examination, or a computed tomography (CT) or positron emission tomography (PET) scan may show enlarged liver, spleen, or lymph nodes.
The most accurate way to diagnose lymphoma is by obtaining a biopsy of the enlarged or abnormal tissue. A biopsy involves surgically removing a small tissue sample and looking at the specimen under a microscope by the pathologist. As we begin to know more about the biology of lymphoma, the nomenclature and sub-classification are also evolving to be more complex. Hence histological interpretation by an experienced haemato-pathologist is important especially if we are dealing with the rarer entities. Lymphoma can also present in bone marrow, and in some instances, the diagnosis is made by bone marrow biopsy
Bone marrow biopsy
Fluid or tissue is collected from the bone marrow by inserting a needle into the hipbone in order to remove a bone marrow sample. It is then sent to the laboratory to test for the presence of Lymphoma cells.
Various imaging tests may be done to detect the presence of Lymphoma cells in other parts of the body. The tests include: Magnetic Resonance Imaging (MRI), Computed Tomography (CT), chest X-ray, Positron Emission Topography (PET) and ultrasound.
Blood tests may be performed as part of the staging process as well as to assess if the lymphoma has affected the functions of the marrow, kidneys and liver.
You can find out more about treatment options for lymphoma or contact us for an appointment.