A B cell is a type of lymphocyte that produces antibodies to fight infections. These are the most prevalent lymphocytes in the bloodstream and are crucial to building a strong immune system. Not only do they fight infections, they also generate "memory" cells that can be reproduced in the case of a repeat attack.
B Cell Lymphoma occurs when B Cells mutate and become cancerous. Subsequently, as the cancerous B Cells clone themselves, the cancer proliferates.
B cell lymphomas comprise a few dozen individual cancers, that affect the b cells in the lymphatic system. However, the most common type is diffuse large b cell lymphoma (DLBCL), and researchers use the R-IPI for determining survival rates.
This type of lymphoma accounts for 80-90% of all Non-Hodgkin’s Lymphomas (NHL). The other major subset is T-Cell lymphoma.
Types of B cell lymphoma
Lymphomas are categorized according to how the B cells are affected. An in-depth list of lymphoma classifications is available for reference. Please select a link for a specific lymphoma or group of lymphomas.
Causes and Risk Factors of B cell lymphoma
B cell lymphomas usually have genetic origins, though they are also linked to environmental factors, immunodeficiency, viruses, and connective tissue disorders. To put it bluntly, there is no truthful answer to, "What causes B cell lymphoma?" The "causes" are not entirely understood, so it is more helpful to focus on risk factors. Please see "What causes lymphoma?" for more detailed information.
The major risk factors for NHL include
- Immune deficiencies
- These deficiencies can be genetic, drug-induced, linked to organ transplants, caused by chemical exposure, or be the result of other diseases such as HIV/AIDS.
- Autoimmune diseases
- The immune system constantly attacks a certain part of the body.
- Chronic infections
- These cause the immune system to generate new lymphocytes at a high rate, thereby increasing the risk of cancerous mutation.
Symptoms of Non-Hodgkin Lymphoma are varied, but may include some or all of the following
- Swollen lymph nodes in the neck, armpits, and/or groin.
- Unintentional or unexplained weight loss.
- Night sweats
- Fatigue or tiredness
- High fever
- Pain or bloating in the abdomen
- Chest pain or a persistent cough
- Difficulty breathing
These symptoms are also indicators of many other diseases, so your doctor will have to run specialized tests to make an accurate diagnosis.
The first step in any diagnosis is a physical exam. The doctor will likely search for any swollen nodes and examine your spleen and liver. They will also record a medical history.
If cancer is suspected, the doctor will usually order blood tests. He will do a complete blood count (CBC) to discover the number of white blood cells, red blood cells, and platelets in your blood stream. Abnormal blood counts can be an indicator of lymphoma. The doctor will also check for other indicators, such as Lactate Dehydrogenase (LDH); high levels of LDH can indicate lymphoma.
If blood tests point toward cancer, chest X-rays or cat scans may be performed to check for swollen lymph nodes and other symptoms that the doctor can’t see via physical exam.
The final step in diagnosis is a biopsy. The doctor will remove a small sample of lymph tissue, usually a portion of a lymph node or a whole lymph node, and send it to the lab for analysis. A biopsy will let the doctor know if you have cancer, what type it is, and it will help them stage the disease.
Staging is an important step in diagnosing cancer. Once the doctor knows the type of cancer, they will need to determine the extent of the cancer’s metastasis, or spread throughout the body. This affects the type of treatment a patient needs.
The stages of lymphoma are:
- Stage I
- In this stage, the tumor is restricted to one lymph group. For example, if the tumor has not spread beyond a cluster of lymph nodes in the neck, it is Stage I.
- Stage II
- In this stage, the lymphoma has spread and involves two lymph groups, which are on the same side (above or below) of the diaphragm. For example, if two lymph groups in the neck are involved, it is classified as Stage II. It is also possible for the lymphoma to affect one group of lymph nodes and a nearby organ in this stage, rather than two lymph groups.
- Stage III
- In this stage, the lymphoma is found on both sides of the diaphragm. One organ near the affected lymph groups may contain abnormal cells as well.
- Stage IV
- This is the most progressed stage of lymphoma and is marked by the involvement of more than one organ. Spread to the bone marrow, blood, and/or liver also indicates Stage 4 disease.
- This stage of lymphoma indicates that the disease has come back after previous remission after treatment.
Grades of cancer are also used. The designated grades are "A" and "B".
- Grade "A" cancer
- You have not suffered weight loss or experienced a high fever or night sweats.
- Grade "B"
- You have suffered weight loss and/or experienced a high fever or night sweats.
Doctors may use one or more of these tests in the staging process:
- A bone marrow biopsy
- A PET scan
- A CT scan with contrast
- An MRI
- A spinal tap
- An ultrasound
These tests will identify the spread of the disease for accurate staging.
Treatment for B Cell Lymphoma differs based on the type of cancer and the staging. It also depends on how fast the cancer is growing and the patient’s age and medical history. A medical oncologist, hematologist, or radiation oncologist will treat the patient with the most aggressive and successful treatment that his or her body can handle.
Follicular lymphoma treatments may include
- This type of treatment is used on patients with indolent (slow-growing) cancers and aggressive cancers. High-dose chemotherapy is needed for very aggressive diseases.
- Radiation therapy
- This therapy is used for indolent lymphomas in the early stages (Stage I and II) and may be used for aggressive cancers of any stage.
- Radioimmunotherapy (radiolabeled monoclonal antibodies)
- Radioimmunotherapy combines monoclonal antibody therapy with radioactive isotopes. Though it was developed in the 1980's, radioimmunotherapy is just now beginning to gain widespread acceptance. In the United States, it has been approved by the FDA for treatment of certain refractory and relapse NHL's. The Zevalin® regimen has been approved by the FDA as a first-line radioummunotherapy treatment for certain follicular lymphoma patients.
- Stem Cell Transplantation
- This therapy is used for very aggressive cancers and for patients who have relapsed, or had a recurrence of a previously treated cancer.
- Watchful Waiting
- For indolent cancers that are diagnosed before symptoms present, doctors may carefully monitor patients without administering treatment. Chemotherapy or radiation will begin when symptoms present, thus making medical intervention necessary.
B cell Lymphoma Articles
Image: Blood smear from an adult male with a marked lymphocytosis. This morphology is characteristic of the majority of cases of Chronic Lymphocytic Leukemia