B-Cell Lymphoma

Overview

B-cell lymphoma is a type of cancer that begins in white blood cells called B lymphocytes, which are part of the body's immune system. This type of cancer affects the lymphatic system; the lymphatic system is a defense network that protects the body against infections and diseases.

B lymphocytes normally fight bacteria, viruses, and other foreign substances by producing antibodies. However, in B-cell lymphoma, these cells begin to multiply uncontrollably and accumulate in the lymph nodes, spleen, bone marrow, or other organs. This accumulation leads to swelling of the lymph nodes and disruption of the body's normal functions.

Lymphomas are divided into two main groups: Hodgkin lymphoma and non-Hodgkin lymphoma. This distinction is made based on the cell type seen under the microscope. Hodgkin lymphoma contains characteristic giant cells called "Reed-Sternberg cells." If these cells are absent, non-Hodgkin lymphoma is diagnosed. B-cell lymphomas can be found in both Hodgkin and non-Hodgkin categories, but they constitute the vast majority of non-Hodgkin lymphomas. Non-Hodgkin lymphomas account for approximately 85-90 percent of all lymphomas, and the majority of these are of B-cell origin.

B-cell lymphomas are divided into many different subtypes. The most commonly seen types are diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma. Some types grow slowly and can remain symptom-free for years; these are called "indolent" (slow-growing) lymphomas. Others grow rapidly and require urgent treatment; these are called "aggressive" lymphomas.

Many types of B-cell lymphoma can be controlled or completely cured with treatment. Advances in chemotherapy, immunotherapy, and targeted therapies have significantly increased survival rates in recent years. Early diagnosis and appropriate treatment are life-saving.

B-cell lymphoma can occur at any age, but risk increases with age. Most cases are diagnosed over age 60. It is slightly more common in men than women.

Symptoms

B-cell lymphoma symptoms vary depending on its type, location, and how much it has spread. Some people feel no symptoms initially, while others present with obvious symptoms.

B-cell lymphoma symptoms include the following:

• Painless lymph node swelling. This is the most common and most characteristic symptom. Swollen lymph nodes are noticed in the neck, armpit, or groin. These swellings are generally painless and can grow over time. Sometimes a single lymph node, sometimes swelling occurs in multiple areas. Unlike lymph node swellings in normal infections, these swellings do not shrink even after weeks pass.
• Unexplained fever. There may be regular or intermittent fever even without infection. It is usually low-grade fever but can sometimes rise above 38°C. Fever rises especially at night.
• Night sweats. Severe night sweats enough to soak the sheets is a typical symptom. The person wakes up sweaty at night and pajamas need to be changed. This sweating is different from normal heat or fatigue.
• Weight loss. Losing more than 10 percent of body weight in an unexplained manner in the last six months. For example, a person weighing 70 kilos loses 7 kilos or more. Weight loss may be accompanied by loss of appetite.
• Extreme fatigue. A deep exhaustion and energy loss that makes daily activities difficult is felt. It is a persistent fatigue that does not go away with rest.
• Itching. There may be widespread, unexplained itching throughout the body. This itching is especially disturbing at night and there may be no visible rash on the skin.
• Chest or abdominal swelling. When lymph nodes inside the chest or abdomen enlarge, there may be shortness of breath, cough, chest pain, or abdominal swelling. Swelling and fullness in the abdomen may result from spleen or liver enlargement.
• Easy bruising or bleeding. Platelet count may drop due to bone marrow involvement. In this case, bruising occurs even with minor trauma, bleeding from gums or nosebleeds may be seen.
• Frequent infections. Infections are frequently experienced because the immune system is weakened. Pneumonia, urinary tract infections, or skin infections may recur.

There are three important symptoms called "B symptoms": unexplained fever, night sweats, and weight loss. Seeing these three symptoms together may indicate that the disease is more aggressive and affects the treatment plan.

When to See a Doctor

Lymph node swelling and other symptoms can result from many different causes and most are harmless. However, in some cases, doctor evaluation is definitely needed.

See a doctor in the following situations:

• If you have noticed painless swelling in the neck, armpit, or groin
• If lymph node swelling lasts longer than two weeks
• If lymph nodes are gradually getting larger
• If you have unexplained persistent fever
• If you sweat enough to soak the sheets at night
• If you have lost weight for no reason in the last six months (more than 10 percent)
• If you are experiencing persistent, unexplained fatigue
• If you have unexplained itching throughout the body
• If bruising occurs frequently or you have become prone to bleeding easily

In most cases, the cause of these symptoms is not lymphoma; it may be infection or other benign conditions. However, definitive distinction can only be made with doctor examination and tests. Early diagnosis increases the chance of treatment.

Causes

The exact cause of B-cell lymphoma is not known in most cases. However, scientists know that changes (mutations) occurring in the DNA of B lymphocytes lead to this cancer.

The process leading to B-cell lymphoma works as follows:

• DNA mutations. Errors occur in the DNA of B lymphocytes. These errors cause cells to multiply much faster than normal and to continue living when they should die. As a result, abnormal B cells accumulate.
• Uncontrolled cell multiplication. Normal B cells are produced when needed and die after completing their tasks. In lymphoma cells, this control mechanism is disrupted and cells continue to multiply continuously.
• Accumulation in lymph nodes and organs. Abnormal B cells accumulate in lymph nodes, spleen, bone marrow, and sometimes other organs. This accumulation leads to swelling of lymph nodes and disruption of normal organ functions.
• Weakening of the immune system. Abnormal B cells cannot perform normal immune functions. Therefore, the body becomes vulnerable to infections.

What exactly causes these mutations is often unclear. In some cases, infections, immune system disorders, or exposure to certain chemicals may play a role.

Risk Factors

Knowing the risk factors for B-cell lymphoma is important, but having a risk factor does not necessarily mean you will develop the disease. Many people develop lymphoma without risk factors; conversely, some with risk factors never get sick.

Risk factors for B-cell lymphoma are as follows:

• Age. Risk increases with age. Although B-cell lymphoma can occur at any age, most cases are over age 60. Some subtypes are more common in younger people.
• Sex. There is slightly higher risk in men compared to women. However, some subtypes may be more common in women.
• Immune system disorders. HIV/AIDS, autoimmune diseases (such as rheumatoid arthritis, Sjögren's syndrome, lupus), or immunodeficiency diseases increase risk.
• Immunosuppressive medications. Medications used after organ transplant or medications used in the treatment of some autoimmune diseases elevate risk.
• Certain infections. Epstein-Barr virus (EBV), Helicobacter pylori bacteria, hepatitis C virus, and human T-cell leukemia virus (HTLV-1) are associated with some lymphoma types.
• Chemical and radiation exposure. Prolonged exposure to pesticides, herbicides, benzene, and other chemicals may increase risk. Previous radiotherapy is also a risk factor.
• Familial predisposition. If there is a history of lymphoma in first-degree relatives, risk increases slightly. However, lymphoma is not a hereditary disease.
• Obesity. Excess weight may be a risk factor for some lymphoma types.
• Previous cancer treatment. Having received chemotherapy or radiotherapy for another cancer before can increase lymphoma risk years later.

Diagnosis

B-cell lymphoma is diagnosed with physical examination, imaging tests, and laboratory analyses. A lymph node or tissue sample must be taken for definitive diagnosis.

The methods used in the diagnosis of B-cell lymphoma are as follows:

• Physical examination. The doctor palpates (checks with hands) swollen lymph nodes. The neck, armpit, groin, spleen, and liver size are evaluated. General health status and symptoms are queried.
• Blood tests. Complete blood count (CBC) measures blood cell counts. If lymphoma has affected the bone marrow, red blood cells, white blood cells, or platelets may be low. Liver and kidney function tests are performed. Some markers such as LDH (lactate dehydrogenase) and beta-2 microglobulin may be high.
• Lymph node biopsy. Tissue sample is taken from a swollen lymph node for definitive diagnosis. There are two types of biopsy: excisional biopsy (removal of the entire lymph node - preferred method) or core needle biopsy (sampling with a thick needle). The tissue sample is examined under a microscope, special stains and immunohistochemistry tests are performed.
• Bone marrow biopsy. To check whether lymphoma has spread to the bone marrow, a bone marrow sample is taken from the hip bone with a thin needle. It is a procedure performed under local anesthesia.
• Imaging tests. Imaging is done to determine how much the disease has spread (staging) in the body. Computed tomography (CT), positron emission tomography (PET-CT), magnetic resonance imaging (MRI), or ultrasonography may be used. PET-CT is especially valuable because it shows active lymphoma cells.
• Lumbar puncture (spinal tap). In some aggressive lymphoma types, a spinal tap may be done to check whether lymphoma has spread to the brain and spinal fluid.
• Molecular and genetic tests. Special genetic changes (chromosomal rearrangements, gene mutations) are searched for in lymphoma cells. These tests help determine the lymphoma subtype and plan treatment. Tests such as FISH (fluorescence in situ hybridization) and flow cytometry may be performed.

After making the diagnosis, the lymphoma type and stage are determined. Staging shows how much the disease has spread and affects the treatment decision. Stages range from I-IV; Stage I is the most limited, Stage IV is the most widespread disease.

Treatment

B-cell lymphoma treatment is personalized depending on the lymphoma type, stage, patient's age, and general health status. Some slow-growing lymphomas do not require immediate treatment; a "watch-and-wait" approach may be applied. Aggressive lymphomas require urgent treatment.

The methods used in B-cell lymphoma treatment are as follows:

• Chemotherapy. These are powerful drugs that kill cancer cells. Usually a combination of multiple drugs is used. The most common chemotherapy regimen is R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone). Treatment usually lasts 3-6 months and is given in cycles. Chemotherapy is given intravenously.
• Immunotherapy. It stimulates the body's immune system to fight cancer. Rituximab is the most commonly used immunotherapy drug; it binds to the CD20 protein on the surface of B cells and causes the cells to be destroyed. It is usually given together with chemotherapy. Other immunotherapy drugs include obinutuzumab and ofatumumab.
• Targeted therapies. These are drugs that target specific proteins or gene changes found in cancer cells. For example, ibrutinib, acalabrutinib, and venetoclax are used in some lymphoma types. These drugs are usually in oral tablet form.
• Radiotherapy. It kills lymphoma cells with high-energy rays. It is generally used in limited stages (Stage I-II) or for disease remaining in some areas. Radiotherapy lasts several weeks in daily sessions.
• Stem cell transplant (bone marrow transplant). After high-dose chemotherapy or radiotherapy, the patient's own stem cells (autologous) or stem cells obtained from a donor (allogeneic) are given to the patient. This treatment is used in recurrent or resistant lymphoma. Allogeneic transplant is more risky but potentially curative.
• CAR T-cell therapy. The patient's own immune cells (T cells) are taken, genetically modified in the laboratory to recognize and destroy lymphoma cells, then given back to the patient. This treatment is very effective in some resistant lymphoma types but is costly and has side effect risk.
• Watch-and-wait (active surveillance). Slow-growing (indolent) lymphomas sometimes do not require immediate treatment. The patient is monitored with regular checkups and treatment is started when the disease begins to create symptoms or progresses. This approach avoids unnecessary treatment side effects.

During treatment, supportive treatments are also important: anti-nausea medications, antibiotics to prevent infections, blood transfusions, and growth factors.

Complications

B-cell lymphoma and its treatment can lead to some complications. With early diagnosis and appropriate treatment, these risks can be reduced.

Complications that may be seen in B-cell lymphoma are as follows:

• Immune system weakness and infections. Both lymphoma and treatment weaken the immune system. Pneumonia, septicemia (blood infection), fungal infections, and other serious infections can develop. Prophylactic antibiotics may be given to prevent infections.
• Bone marrow suppression. Chemotherapy affects the bone marrow and reduces blood cell production. Anemia (low red blood cells), neutropenia (low white blood cells), and thrombocytopenia (low platelets) can develop. Blood transfusions or growth factors may be needed.
• Tumor lysis syndrome. Especially in aggressive lymphomas, after treatment begins, cancer cells break down rapidly and harmful substances are released into the bloodstream. It can lead to kidney failure, heart rhythm disorders, and other serious problems. Plenty of fluids are given and medications are used to prevent it.
• Organ damage. Lymphoma can affect the liver, kidneys, lungs, or heart. Some chemotherapy drugs can also lead to organ toxicity (for example, doxorubicin can damage the heart).
• Secondary cancers. Lymphoma treatment can lead to other cancers (such as acute leukemia, lung cancer, breast cancer) years later. The risk is low but long-term follow-up is important.
• Neurological problems. Some chemotherapy drugs can damage nerves, causing numbness, tingling, and pain in the hands and feet (peripheral neuropathy). Rarely, lymphoma can spread to the brain or spinal cord.
• Fertility problems. Chemotherapy and radiotherapy can damage reproductive organs, leading to infertility. Young patients can evaluate fertility preservation options such as egg or sperm freezing before treatment.
• Psychosocial problems. Lymphoma diagnosis and the treatment process can lead to depression, anxiety, and stress. Psychological support and counseling are beneficial.

Living with B-Cell Lymphoma

Receiving a B-cell lymphoma diagnosis is a life-changing experience. However, with modern treatments, many patients achieve long-term remission (disappearance of disease symptoms) or are completely cured. The basic principles of living with lymphoma are regular follow-up, healthy lifestyle, and receiving emotional support.

During the Treatment Process

Coping with side effects during treatment is important. Chemotherapy can lead to side effects such as nausea, hair loss, fatigue, and mouth sores. Your doctor will recommend medications to reduce these side effects.

Pay attention to nutrition. Good nutrition helps tolerate treatment. Consume protein-rich, balanced meals. If you have nausea, prefer small frequent meals. For plenty of fluids, you can drink water, fruit juices, or soup. Avoid alcohol and processed foods.

Maintain good oral hygiene. Use a soft toothbrush and gentle dental floss. If mouth sores develop, gargle as your doctor recommends.

Protect yourself from infections. Wash hands frequently, avoid crowded places, stay away from contact with sick people. Report even a slight fever to your doctor immediately.

Remission and Follow-up

If you enter remission after treatment is completed, regular follow-ups are very important. See your doctor frequently in the first few years (every 3-6 months), then at less frequent intervals (once a year) later.

Physical examination, blood tests, and imaging when necessary are done during follow-ups. Pay attention to relapse (disease recurrence) symptoms: new lymph node swellings, fever, night sweats, weight loss. Any suspicious symptom should be reported to your doctor immediately.

Physical and Emotional Recovery

Physical recovery after treatment takes time. Fatigue can last for months. Give yourself time, rest, but do light exercise when possible. Walking, yoga, or swimming increases energy levels and improves mood.

Emotionally, lymphoma diagnosis and the treatment process can be traumatic. Feeling fear, anxiety, sadness, and anger is normal. Share your feelings with loved ones. Don't hesitate to seek support from a psychologist or psychiatrist. Participating in cancer support groups is also very valuable; connecting with people who have had similar experiences makes you feel you are not alone.

Healthy Lifestyle

Eat healthy. Consume plenty of vegetables, fruits, whole grains, and lean protein. Limit processed foods, red meat, and sugar-rich foods.

Exercise regularly. Aim for at least 150 minutes of moderate-paced activity per week. Exercise strengthens the immune system, reduces fatigue, and improves overall health.

Quit smoking and limit alcohol. Smoking increases the risk of secondary cancer and slows recovery.

Manage stress. Meditation, deep breathing exercises, hobbies, and social activities reduce stress.

Sleep adequately. The body repairs during sleep. Aim for 7-8 hours of quality sleep at night.

Return to Work and Normal Life

The decision to return to work after treatment is personal. Some patients continue working during treatment, some rest and then return. Communicate openly with the employer. Request flexible working hours or part-time work if necessary.

Return gradually to normal activities. Maintain social relationships, engage in hobbies, do things you enjoy. Quality of life and happiness are an important part of recovery.

Preparing for Your Appointment

What you can do:

• Note your symptoms in detail and when they started
• Mention if there is a family history of cancer
• List all medications, vitamins, and supplements
• Note serious infections or illnesses you have had
• Bring your previous medical records and test results
• Write your questions down in advance
• If possible, bring a family member or friend

Questions you can ask your doctor are as follows:

• What is the exact type of my B-cell lymphoma?
• What stage is my disease?
• What are my treatment options?
• What are the side effects of the recommended treatment?
• How long will treatment take?
• What is my prognosis (course of the disease)?
• What is my risk of relapse?
• Can I participate in clinical trials?
• When can I return to work?
• What changes should I make in my lifestyle?

Questions your doctor may ask you are as follows:

• When did your symptoms start?
• Is the lymph node swelling painful?
• Are you experiencing fever, night sweats, or weight loss?
• What is your fatigue level?
• Have you had an infection recently?
• Is there a family history of lymphoma or other cancer?
• Do you have diseases affecting your immune system?
• Have you received chemotherapy or radiotherapy before?
• Have you been exposed to chemicals or pesticides?