What Is Lymphoma? Symptoms, Types, Diagnosis and Treatment
Contents
- What Is Lymphoma?
- What Are the Types of Lymphoma?
- What Is Hodgkin Lymphoma?
- What Is Non-Hodgkin Lymphoma?
- What Causes Lymphoma and What Are the Risk Factors?
- What Are the Symptoms of Lymphoma?
- What Are B Symptoms?
- Does Every Swollen Lymph Node Mean Lymphoma?
- How Is Lymphoma Diagnosed?
- Why Is Biopsy Important?
- How Is Lymphoma Staged?
- How Is Lymphoma Treated?
- Does Every Lymphoma Need Immediate Treatment?
- What Are Targeted Therapy, Immunotherapy and CAR-T?
- When Is Stem Cell Transplant Used?
- When Should You See a Doctor?
- Frequently Asked Questions
Lymphoma is the collective name for cancers that develop from lymphocytes, which are cells of the immune system. Because lymphocytes are found in lymph nodes, the spleen, bone marrow, blood and many tissues throughout the body, lymphoma is not simply a cancer of the lymph nodes.
Lymphoma includes many biologically distinct diseases. Some lymphomas grow slowly and may initially require monitoring alone, whereas others are aggressive and require treatment soon after diagnosis.
What Is Lymphoma?
The lymphatic system is an important part of the immune system and includes lymph nodes, lymphatic vessels, the spleen, thymus and lymphoid tissues.
Lymphoma develops when B lymphocytes, T lymphocytes or NK cells acquire biological changes that allow abnormal growth and survival.
The clinical behaviour of the disease depends greatly on its cell of origin and its pathological and molecular characteristics.
What Are the Types of Lymphoma?
Lymphomas are traditionally divided into two broad groups:
- Hodgkin lymphoma
- Non-Hodgkin lymphomas
This is only the first level of classification. Modern lymphoma classification uses morphology, immunophenotype, cell of origin, genetics and molecular features to define many distinct diseases.
What Is Hodgkin Lymphoma?
Hodgkin lymphoma is less common than the broad group of non-Hodgkin lymphomas.
The most common form is classical Hodgkin lymphoma, in which characteristic Reed-Sternberg cells and the surrounding cellular environment can be identified on pathological examination.
Treatment depends on stage, age, risk factors and response to therapy and can include chemotherapy, immunotherapy-containing combinations and radiotherapy in selected patients.
What Is Non-Hodgkin Lymphoma?
Non-Hodgkin lymphoma is not one disease. It includes numerous B-cell, T-cell and NK-cell lymphoma subtypes.
They can broadly behave as:
- Indolent or slow-growing lymphomas
- Aggressive or rapidly growing lymphomas
For example, follicular lymphoma often follows a slower course, while diffuse large B-cell lymphoma is an aggressive lymphoma for which cure may be the treatment goal in many patients.
What Causes Lymphoma and What Are the Risk Factors?
In most people with lymphoma, no single cause can be identified.
Factors associated with an increased risk in certain lymphoma subtypes include:
- Increasing age for some lymphoma types
- Immunosuppression
- Immunosuppressive treatment after organ transplantation
- HIV infection
- Certain autoimmune diseases
- Certain viral or bacterial infections
- Family history of some lymphoid malignancies
- Previous exposure to some chemotherapy or radiotherapy treatments
Epstein-Barr virus is associated with some Hodgkin and non-Hodgkin lymphoma subtypes, while Helicobacter pylori is associated with some gastric MALT lymphomas.
What Are the Symptoms of Lymphoma?
Symptoms vary according to the lymphoma subtype and the part of the body involved.
Possible symptoms include:
- Painless swelling of lymph nodes in the neck, armpit or groin
- Unexplained fever
- Drenching night sweats
- Unintentional weight loss
- Persistent fatigue
- Itching
- Reduced appetite
- Abdominal fullness or swelling
- Persistent cough or shortness of breath
Enlarged lymph nodes within the chest may cause cough, chest pressure or shortness of breath. An enlarged spleen can cause abdominal fullness or early satiety.
What Are B Symptoms?
Certain systemic symptoms used in lymphoma assessment are referred to as B symptoms.
They classically include:
- Unexplained fever above 38°C
- Drenching night sweats
- Unintentional loss of more than 10% of body weight within 6 months
These findings can contribute to staging and risk assessment in some Hodgkin and non-Hodgkin lymphomas.
Does Every Swollen Lymph Node Mean Lymphoma?
No. Infections and benign immune reactions are common causes of enlarged lymph nodes.
Medical assessment is particularly appropriate when a node:
- Does not reduce over several weeks
- Continues to enlarge
- Feels hard or fixed
- Is located above the collarbone
- Occurs with fever, night sweats or unexplained weight loss
Whether a lymph node is painful or painless does not by itself distinguish lymphoma from benign conditions.
How Is Lymphoma Diagnosed?
Evaluation generally begins with medical history and physical examination.
Depending on the clinical situation, tests can include:
- Complete blood count
- Kidney and liver-function tests
- LDH and other relevant laboratory tests
- Biopsy of a lymph node or involved tissue
- CT
- PET-CT
- MRI in selected situations
- Bone-marrow assessment in selected patients
Not every patient requires every test. Investigations are tailored to the suspected lymphoma subtype and clinical circumstances.
Why Is Biopsy Important in Lymphoma?
A tissue sample is generally required to establish a definitive lymphoma diagnosis.
A specialist pathologist can evaluate:
- Microscopic morphology
- Immunohistochemistry
- Flow cytometry where appropriate
- Relevant genetic and molecular abnormalities
When practical, an excisional biopsy or another method that provides adequate tissue can make accurate lymphoma classification easier. Image-guided core biopsy may be appropriate in some settings.
Blood tests, ultrasound or PET-CT alone do not establish the definitive histological subtype of lymphoma. Adequate pathological tissue is important before treatment is planned whenever clinically feasible.
How Is Lymphoma Staged?
Many Hodgkin and non-Hodgkin lymphomas use stages I to IV to describe the distribution of disease.
- Stage I: Usually one lymph-node region or one limited extranodal site
- Stage II: More than one lymph-node region on the same side of the diaphragm
- Stage III: Lymph-node involvement on both sides of the diaphragm
- Stage IV: Disseminated extranodal or bone-marrow involvement in appropriate lymphoma types
Not all lymphoma subtypes use the same staging system, and disease-specific prognostic scores may also be important.
How Is Lymphoma Treated?
There is no single treatment regimen for all lymphomas.
Treatment depends on:
- Exact pathological subtype
- Stage
- Molecular and biological characteristics
- Rate of disease progression
- Age
- General health
- Previous treatment
Options can include:
- Active monitoring
- Chemotherapy
- Monoclonal antibodies
- Targeted therapy
- Immunotherapy
- Radiotherapy
- Stem cell transplantation
- CAR-T cell therapy
- Bispecific antibody therapy
Not all of these treatments are appropriate for every lymphoma subtype.
Does Every Lymphoma Need Immediate Treatment?
No.
Some slow-growing lymphomas can be managed with active monitoring or watch and wait when there are no symptoms, threatening organ effects or other indications to begin treatment.
This does not mean that the disease is ignored. Patients are monitored with clinical review, blood tests and imaging when appropriate.
What Are Targeted Therapy, Immunotherapy and CAR-T?
Monoclonal Antibodies
These medicines recognise specific proteins on lymphoma cells. Antibodies targeting CD20, for example, play an important role in many B-cell lymphoma treatments.
Targeted Therapies
Targeted treatments interfere with molecular pathways that lymphoma cells use to grow and survive. The appropriate drug depends on the lymphoma subtype and its biological characteristics.
Checkpoint Inhibitors
PD-1-directed immunotherapies can be used in selected patients with Hodgkin lymphoma and work by enhancing immune recognition of lymphoma cells.
Bispecific Antibodies
Bispecific antibodies used in selected relapsed or refractory B-cell lymphomas are designed to bring immune T cells into close contact with lymphoma cells.
CAR-T Cell Therapy
In CAR-T therapy, a patient's T cells are collected and genetically modified in a laboratory so that they can recognise a specific target on lymphoma cells before being returned to the patient.
CAR-T is an advanced cellular therapy used for selected relapsed or treatment-resistant B-cell lymphomas.
When Is Stem Cell Transplant Used in Lymphoma?
Stem cell transplantation is not required for every patient.
It can form part of treatment in selected:
- Relapsed
- Refractory
- High-risk
lymphomas.
Autologous stem cell transplantation, using the patient's own previously collected stem cells after intensive treatment, is commonly used in appropriate lymphoma settings.
Allogeneic transplantation using donor cells may be considered in selected situations.
When Should You See a Doctor?
Medical assessment is appropriate for:
- A lymph node that does not reduce over several weeks or continues to enlarge
- Unexplained recurrent fever
- Drenching night sweats
- Significant unintentional weight loss
- Persistent unexplained fatigue
- Persistent unexplained itching
- Unexplained abdominal fullness or early satiety
- Persistent cough or breathlessness
Sudden or rapidly worsening shortness of breath, significant chest pressure, swelling of the face or neck, altered consciousness or severe clinical deterioration requires urgent medical assessment.
Have Persistent Lymph-Node Enlargement Assessed
Persistent lymph-node enlargement, night sweats, unexplained fever or weight loss can be assessed with clinical examination and appropriate further investigations.
Frequently Asked Questions
References
- Academic Hospital. Lenf Kanseri (Lenfoma) Nedir? Belirtileri ve Nedenleri
- World Health Organization / IARC. WHO Classification of Tumours: Haematolymphoid Tumours, 5th Edition
- European Society for Medical Oncology. ESMO Living Guideline: Lymphomas
- National Cancer Institute. Hodgkin Lymphoma Treatment
- National Cancer Institute. Non-Hodgkin Lymphoma Treatment