Lymphomas are cancers arising from lymphocytes, which are a fundamental part of the immune system and which help to protect the body from disease. Lymphomas include Hodgkin’s Disease and various classifications and sub-types of non-Hodgkin’s lymphomas. In addition to a network of lymph vessels and nodes throughout the body, the lymphatic system also includes the bone marrow, spleen, thymus gland, tonsil, and appendix.

Lymphoma is the fifth most common form of cancer in Canada. An estimated 7,890 new cases of lymphoma have been diagnosed in Canada in 2008. Lymphomas now account for approximately 5% of all Canadians with cancer.

There are two primary forms of lymphoma. Hodgkin’s Disease accounts for about 11% of all Canadian lymphomas and is generally considered one of the more curable cancers. Non-Hodgkin’s lymphomas are more prevalent and their cure rates depend on the type or sub-type, the stage, the grade and various prognostic factors. There are more than 30 types and sub-types of Non-Hodgkin's lymphomas.

The incidence of the more prevalent forms of lymphoma, non-Hodgkin’s lymphomas, has increased significantly over the past several decades in Canada. The incidence of Non-Hodgkin's lymphoma in both males and females has stabilized. Until recently, Non-Hodgkin's lymphoma seemed to develop more frequently as people got older, but there has been a marked increase of Non-Hodgkin's lymphoma in children and young adults.

Non-Hodgkin's lymphoma is complex in that there are many different classifications, as well as sub-types and stages of Non-Hodgkin's lymphoma, each with varying treatment options and cure rates. One current hypothesis is that Non-Hodgkin's lymphoma is actually a group of closely related cancers, in which infectious agents and/ or environmental/ occupational exposures may play a role. Some of the challenges of living with lymphomas may include their unpredictability and their recurrence.

"This diagram represents where key lymph nodes are situated throughout the human body. It has been estimated that there are about 600 lymph nodes in the body. The numbers in the diagram denote areas of lymph nodes that frequently are involved in Hodgkin and other lymphomas. These areas of lymph nodes occur around the ears (1) and around the jaw (2). They comprise the tonsils and adenoids (3), are found in the front and back of the neck (4), above and below the collar bone (5), in the armpit (6), near the elbow (7), in the chest (8), in the abdomen (9), in the pelvis (10) and in the groin (11). The spleen (S) contains many clusters of lymphocytes. These clusters may be involved in the malignant process, grow, and lead to involvement and enlargement of the spleen. The gut-associated (intestinal) lymph tissue (G) may also be the site of lymphoma development. Lymphomas are cancers that begin with the malignant transformation of a lymphocyte in the lymphatic system. "Lymph-" indicates that the disease begins in a lymphocyte and "-oma" is a Greek suffix denoting a tumor." - with permission from The Leukemia & Lymphoma Society of Canada.

The symptoms of lymphoma are commonly seen in other, less serious illnesses, such as influenza or other viral infection. These symptoms are often overlooked, but in cases of less serious illnesses they would not last very long. With lymphoma, these symptoms persist over time and cannot be explained by an infection or another disease. The checklist below lists the most common symptoms of lymphoma.

Due to the common nature of these symptoms and because lymphoma symptoms do not appear in all cases, diagnosis is often problematic. If you suspect that you, a family member, friend, or loved one may have lymphoma, see your doctor or qualified medical professional as soon as possible. Early diagnosis makes an impact on treatment and outcome.

"The most common symptoms of lymphoma are:

• painless swelling in the neck, armpit or groin;
• night sweats;
• unexplained fever;
• weight loss and tiredness;
• coughs and breathlessness;
• persistent itch all over the body;
• The swellings associated with non-Hodgkin's lymphoma may also manifest themselves in other parts of the body, for example, the stomach, nervous system or skin.

The only method for accurate diagnosis of lymphoma is a biopsy of an enlarged lymph node."¹

¹ from Lymphoma Coalition

• In certain instances, people feel pain in the lymph nodes after drinking alcohol.
• If the lymphoma involves lymphatic tissue within the abdomen, bowel or stomach, fluid may build up causing swelling near the intestines potentially leading to sensations of abdominal pressure, pain, diarrhea and/or indigestion.
• The enlarged lymph node sometimes causes other symptoms by pressing against a vein (causing a swelling of an arm or leg), or against a nerve (causing pain, numbness, or tingling in an arm or leg).
• Some people experience lower back pain that is unexplained. It is thought that this may be caused by expanding lymph nodes pressing on nerves.
• As lymphomas progress and cancerous lymphocytes spread beyond the lymphatic system, the body loses its ability to fight infection. The generalized symptoms that develop may be confused with signs of influenza, tuberculosis (TB), other infections such as infectious mononucleosis (‘mono’) or other cancers.

"There is no single cause of non-Hodgkin’s lymphoma, but some factors appear to increase the risk of developing it:

• being older and male
• having a weakened immune system due to:
  • take immuno-suppressant drugs after an organ transplant;
  • HIV / AIDS;
  • autoimmune diseases, such as rheumatoid arthritis or Sjogren syndrome;
  • inherited disorders such as ataxiatelangiectasia or Wiskott-Aldrich syndrome;
• infections such as human T-cell leukemia / lymphoma virus (HTLV-1), Epstein Barr virus or Helicobacter pylori (a bacteria);
• exposure to pesticides;
• previous treatment with radiation or chemotherapy.

Most people develop non-Hodgkin’s lymphoma without any of these risk factors."²

"There is no single cause of Hodgkin's lymphoma, but some factors appear to increase the risk of developing it:

• age – particularly between 15 and 35, or older than 50;
• Epstein Barr virus (a virus that causes infectious mononucleosis ('mono') or glandular fever);
• HIV (human immunodeficiency virus);
• family history of Hodgkin lymphoma (especially in a parent, sister or brother).

Some people develop Hodgkin’s disease without any of these risk factors." ³

²p. 3-4, non-Hodgkin’s Lymphoma. Understanding your diagnosis. Canadian Cancer Society brochure , 2008.

³p. 3, Hodgkin’s Lymphoma. Understanding your diagnosis. Canadian Cancer Society brochure , 2008.