Answers to the top questions about lymphoma (Part 1)
To help you learn more about lymphoma, which affects both children and adults, this is the first of two blog posts that will answer the top questions about this disease.
What is lymphoma? Lymphoma is the name for a group of more than 60 types of cancer that start in the lymphatic system, part of the body’s immune system. The role of lymphatic system is to fight infection by capturing and destroying bacteria and viruses. It’s made up of organs (the spleen, thymus, tonsils, appendix, adenoids, and tissue in the small intestine called Peyer’s patches), bone marrow, nodes, and vessels that carry white blood cell-rich lymph fluid throughout the body.
Lymphomas start in white blood cells called lymphocytes. B lymphocytes, or B cells, produce the antibodies that help the body fight bacteria and viruses. T lymphocytes, or T cells, have several functions, including destroying germs and abnormal cells and speeding up or slowing down the activity of other cells in the immune system. These cells become cancerous when they develop a genetic mutation, then multiply rapidly, creating more copies of the mutated cell. The mutation also causes the cells to live longer than healthy cells.
How common is lymphoma? There are more than 845,000 people in the U.S. who are living with lymphoma or in remission from the disease. An estimated additional 74,680 to 83,100 people will be diagnosed with some form of lymphoma in 2018.
Is there more than one type of lymphoma? There are two main types of the disease—Hodgkin lymphoma and non-Hodgkin lymphoma. Non-Hodgkin lymphoma is more common than Hodgkin lymphoma.
For each type of lymphoma, there are several subtypes. The most common types of non-Hodgkin lymphoma are diffuse large B-cell lymphoma and follicular lymphoma. Other types of non-Hodgkin lymphoma include:
- Chronic lymphocytic leukemia /Small lymphocytic lymphoma
- Burkitt lymphoma
- Mantle cell lymphoma
- Marginal zone lymphomas
- Primary mediastinal B cell lymphoma
- Waldenstrom macroglobulinemia (or lymphoplasmacytic lymphoma)
- Hairy cell leukemia
- Cutaneous B-cell and T-cell lymphoma
For Hodgkin lymphoma, 9 out of 10 cases fall into the category of classic Hodgkin lymphoma, which includes four subtypes:
- Nodular sclerosis Hodgkin lymphoma
- Mixed cellularity Hodgkin lymphoma
- Lymphocyte-rich Hodgkin lymphoma
- Lymphocyte-depleted Hodgkin lymphoma
About 5% of the cases of Hodgkin lymphoma fall under the classification of nodular lymphocyte-predominant Hodgkin lymphoma.
Who is at risk for lymphoma? There are several factors that affect your risk of developing lymphoma:
- Age: While non-Hodgkin lymphoma is one of the more common types of cancer diagnosed in children, teens, and young adults, more than half of the people diagnosed with the disease are 65 or older. Hodgkin lymphoma is more commonly diagnosed in people in their 20s or older than 55.
- Weakened immune system: Having HIV or taking medications that suppress the immune system after an organ transplant can increase your risk of both types of lymphoma.
- Gender: Most types of lymphoma are more common in males than females.
- Certain infections: Some bacterial and viral infections, including HIV, Epstein-Barr virus, human herpes virus 8, long-term hepatitis C, and Helicobacter pylori, which causes ulcers, have been associated with an increased risk of developing lymphoma.
- Family history: Having a parent, child, or sibling with non-Hodgkin lymphoma increases your risk, while siblings of young people diagnosed with Hodgkin lymphoma are at higher risk.
Some studies have also linked exposure to some weed and insect killing chemicals and radiation used for cancer treatment with an increased risk of non-Hodgkin lymphoma.
Learn about the symptoms and treatments for lymphoma in the next post in this series.