What is Lymphoma?
Lymphoma is a type of cancer originating in the lymphatic system, part of the body's immune system. The lymphatic system includes the lymph nodes (small, bean-shaped structures that produce and store cells that fight infection and disease), the spleen, thymus, and bone marrow. Lymphoma primarily affects a type of white blood cell known as lymphocytes.
There are two main types of lymphoma:
- Hodgkin Lymphoma (HL): Hodgkin lymphoma, also known as Hodgkin's disease, is a type of cancer that affects the lymphatic system, which is part of the body's immune system. It is characterized by the presence of abnormal cells called Reed-Sternberg cells, which are large, abnormal lymphocyte cells (lymphocytes are a type of immune cell produced in the bone marrow and are found in the blood and lymph tissue).
This cancer typically starts in the lymph nodes, but it can spread to other parts of the body over time. The exact cause of Hodgkin lymphoma is not fully understood, but it is thought to involve a combination of genetic and environmental factors. - Non-Hodgkin Lymphoma (NHL): NHL encompasses a diverse group of blood cancers, including any kind of lymphoma except Hodgkin's. It develops in the lymphocytes, which are white blood cells that play a crucial role in the immune response. NHL can start in lymph nodes but can also affect other parts of the lymphatic system, such as the spleen, tonsils, and bone marrow.
NHL is categorized based on the type of lymphocyte it affects and the characteristics of the cancer cells. The two main types are: - B-Cell Lymphomas: B-cell lymphoma is a type of non-Hodgkin lymphoma (NHL) that originates in B lymphocytes, which are a type of white blood cell crucial to the immune system. B lymphocytes, or B cells, produce antibodies that help the body fight infections. There are several subtypes of B-cell lymphoma, each with different characteristics, prognosis, and treatment approaches. Some common subtypes include:
- Diffuse Large B-Cell Lymphoma (DLBCL) is the most common type of NHL. It is aggressive but potentially curable with appropriate treatment.
- Follicular Lymphoma: A slower-growing, indolent form of lymphoma that may transform into a more aggressive type over time.
- Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL): These are essentially the same disease, but CLL is found in the blood and bone marrow, while SLL is found in the lymph nodes.
- Mantle Cell Lymphoma: An uncommon but aggressive form of lymphoma that often requires intensive treatment.
- Burkitt Lymphoma: A highly aggressive lymphoma more common in children and young adults, often associated with a high growth rate.
- T-Cell Lymphomas: T-cell lymphoma is a type of cancer originating in T-lymphocytes, a subtype of white blood cells crucial for the immune system. It is relatively rare. T-cell lymphomas can be aggressive (fast-growing) or indolent (slow-growing), and their behavior, treatment, and prognosis can vary significantly. Common subtypes include:
- Peripheral T-Cell Lymphoma (PTCL): Includes several subtypes such as PTCL not otherwise specified (PTCL-NOS), angioimmunoblastic T-cell lymphoma (AITL), and anaplastic large cell lymphoma (ALCL).
- Cutaneous T-Cell Lymphoma (CTCL): Primarily affects the skin, with mycosis fungoides and Sézary syndrome being the most common types.
- Adult T-Cell Leukemia/Lymphoma (ATLL): Associated with the human T-cell lymphotropic virus type 1 (HTLV-1).
- Extranodal NK/T-Cell Lymphoma, Nasal Type: Often affects the nasal area but can involve other parts of the body.
Risk Factors
- Age:
- Hodgkin lymphoma is more common in young adults (ages 15-40) and in older adults (after age 55).
- Non-Hodgkin lymphoma is more common in people aged 60 and older.
- Gender:
- Males have a slightly higher risk of developing both Hodgkin and non-Hodgkin lymphoma compared to females.
- Weakened Immune System:
- People with weakened immune systems, such as those with HIV/AIDS, autoimmune diseases, or individuals taking immunosuppressive medications (e.g., after an organ transplant), have a higher risk of lymphoma.
- Infections:
- Epstein-Barr virus (EBV): Linked to certain types of Hodgkin lymphoma and non-Hodgkin lymphoma, especially Burkitt lymphoma.
- Helicobacter pylori: Associated with mucosa-associated lymphoid tissue (MALT) lymphoma.
- Hepatitis C and HIV: These infections can increase the risk of non-Hodgkin lymphoma.
- Family History:
- Having a close family member (like a parent or sibling) with lymphoma slightly increases the risk of developing it.
- Chemical and Radiation Exposure:
- Exposure to certain chemicals, such as pesticides, herbicides, and solvents (e.g., benzene), can increase the risk of non-Hodgkin lymphoma.
- Previous radiation therapy for other cancers can increase the risk of lymphoma.
- Autoimmune Diseases:
- People with autoimmune diseases like rheumatoid arthritis, lupus, and celiac disease may have a higher risk of non-Hodgkin lymphoma.
- Obesity:
- Some studies suggest that obesity may be associated with an increased risk of non-Hodgkin lymphoma.
- Breast Implants:
- Rare cases of anaplastic large cell lymphoma (a type of NHL) have been associated with certain types of breast implants.
Additional Risk Factors for Specific Types of Lymphoma
- Hodgkin Lymphoma (HL):
- History of infectious mononucleosis (mono): Caused by EBV, this viral infection increases the risk of Hodgkin lymphoma.
- Socioeconomic factors: Hodgkin lymphoma is more common in higher socioeconomic groups, possibly due to delayed exposure to certain childhood infections.
- Non-Hodgkin Lymphoma (NHL):
- Infections with HTLV-1 and HHV-8: These viruses are linked to rare types of non-Hodgkin lymphoma.
- Immunodeficiency: Conditions like Wiskott-Aldrich syndrome or common variable immunodeficiency can increase NHL risk.
It's important to note that having one or more of these risk factors does not mean that someone will definitely develop lymphoma. Many people with lymphoma have no known risk factors.
Choosing the cancer center that’s right for you is one of the most important decisions you make in your cancer journey. Understanding and managing lymphoma requires a team approach. At GW Cancer Center, you’ll be treated by one of the region’s most highly-rated Malignant Hematology teams.
