Malignant lymphoma is a type of cancer that originates in lymphocytes, specialized white blood cells that are an important part of the body’s immune system. This condition affects the lymphatic system, a widespread network of tissues and organs. When lymphocytes undergo abnormal changes and multiply uncontrollably, they can form masses or tumors, primarily within lymph nodes but also in other organs.
What Malignant Lymphoma Is and Its Major Types
Malignant lymphoma develops when lymphocytes become cancerous and proliferate rapidly. The lymphatic system is a complex network of vessels, tissues, and organs, including lymph nodes, the spleen, the thymus, and bone marrow. This system drains fluid from tissues, returns it to the bloodstream, and filters out harmful substances.
Lymphoma cells can accumulate in lymph nodes, causing them to swell, or they can affect other organs. The specific type of lymphocyte involved, either B cells or T cells, influences the classification. There are many types of malignant lymphoma.
The two main categories are Hodgkin lymphoma (HL) and Non-Hodgkin lymphoma (NHL). The primary difference is the presence of Reed-Sternberg cells, found in HL but absent in NHL. Hodgkin lymphoma often begins in the upper body, such as the neck, chest, or armpits, and tends to spread predictably.
Non-Hodgkin lymphoma is more common, accounting for approximately 90% of all lymphoma cases, and encompasses a diverse group of subtypes. These can be broadly categorized as aggressive (fast-growing) or indolent (slow-growing). Examples of aggressive NHL include diffuse large B-cell lymphoma (DLBCL) and Burkitt lymphoma, while follicular lymphoma is a common indolent subtype.
Signs and Symptoms
The signs and symptoms of malignant lymphoma can vary depending on the type and location of the cancer. A common indicator is a painless swelling of lymph nodes, often noticeable in the neck, armpit, or groin. These swollen nodes may feel firm or rubbery.
Many individuals with lymphoma also experience general symptoms often referred to as “B symptoms.” These include unexplained fever, drenching night sweats, and unexplained weight loss. Other symptoms can include persistent fatigue, generalized itching without a rash, and a loss of appetite.
If lymphoma affects lymph nodes in the chest, it may lead to symptoms such as chest pain, a persistent cough, or shortness of breath. Abdominal involvement can cause pain or a feeling of fullness due to an enlarged liver or spleen. These symptoms can also be caused by less serious conditions, but persistent or unusual symptoms warrant medical evaluation.
How Malignant Lymphoma is Diagnosed
The diagnostic process for malignant lymphoma begins with a physical examination and a review of the patient’s medical history. A healthcare professional will check for swollen lymph nodes in areas like the neck, armpits, and groin, and may assess for an enlarged spleen or liver.
A definitive diagnosis requires a biopsy, which involves removing a tissue sample for microscopic analysis. The biopsy is important to confirm the presence of cancer cells and identify the specific type of lymphoma, including the presence or absence of Reed-Sternberg cells.
Imaging tests play an important role in determining the extent of the disease, a process known as staging. These tests, such as CT, MRI, and PET scans, help visualize where the lymphoma has spread. Blood tests are also performed to assess overall health and organ function, though they alone do not diagnose lymphoma.
A bone marrow exam, consisting of both an aspiration and a biopsy, may be performed to determine if lymphoma cells have spread to the bone marrow. This procedure involves taking samples from the hip bone. These diagnostic procedures provide the information needed for an accurate diagnosis and treatment plan.
Treatment Options
Treatment for malignant lymphoma is individualized, depending on the specific type, stage, and overall health of the patient. Chemotherapy is a common treatment, using medicines, often given intravenously or in pill form, to kill or slow the growth of cancer cells. These drugs target rapidly dividing cells, including lymphoma cells.
Radiation therapy uses targeted radiation to destroy cancer cells and shrink tumors. For some slow-growing lymphomas, a “watch and wait” approach, also known as active surveillance, may be recommended. This involves closely monitoring the patient’s health and lymphoma signs before initiating treatment.
Immunotherapy harnesses the body’s own immune system to fight cancer. This can involve monoclonal antibodies, which attach to lymphoma cells and signal the immune system to eliminate them. A specialized form, CAR T-cell therapy, involves genetically modifying a patient’s T cells to recognize lymphoma cells, then reinfusing them to target and destroy the cancer.
Targeted therapy uses drugs that specifically interfere with molecular pathways involved in cancer cell growth and survival, often with fewer side effects than traditional chemotherapy. Stem cell transplantation, sometimes referred to as bone marrow transplantation, may be considered for high-risk cases or if the lymphoma recurs. This involves replacing diseased bone marrow with healthy stem cells, often after high-dose chemotherapy.