T lymphocytes (T cells) and B lymphocytes (B cells) are two types of white blood cells that perform immune functions in the lymphatic system. B-cells produce antibodies to attack bacteria and viruses that enter the body. T cells directly attack foreign invaders and cancer cells and produce chemicals that activate other immune cells.
Lymphoma, a cancer of the lymphatic system, is grouped into two major types—Hodgkin’s and non-Hodgkin’s. Hodgkin’s lymphoma is a B-cell lymphoma.
Non-Hodgkin’s lymphoma is further divided into over 60 subtypes. B-cell lymphomas are the most common type of lymphoma. More than 90% of non-Hodgkin’s lymphomas in people in Western countries are B cell in origin. T-cell lymphoma is less common, with about 10% of non-Hodgkin’s lymphomas starting in T cells (although this is higher in Asia).
This article will review the types of T-cell lymphomas, why they develop, as well as how they are diagnosed and treated.
Types of T-Cell Lymphoma
Multiple types of T-cell lymphoma exist, some of which are slow growing (indolent) and others of which grow much more quickly and are more aggressive. All T-cell lymphomas are rare. Some examples of different T cell lymphomas include:
T-lymphoblastic lymphoma/leukemia: This type most commonly occurs in teens or young adults. It starts in the thymus gland, a lymphatic organ in the chest. It is an aggressive cancer but curable if caught early. Cutaneous T cell lymphomas (mycosis fungoides, Sezary syndrome): These T-cell lymphomas start in the skin, and can have a rash-like appearance that spreads across the body. Initially, they may be indolent lymphomas but can become aggressive and move to internal organs. Adult T-cell lymphoma/leukemia: This lymphoma is caused by a virus and is most common in areas of the world such as Japan, Africa, and the Caribbean. It has different types that can be aggressive or indolent. Extra-nodal natural killer/T-cell lymphoma, nasal type: This is an aggressive lymphoma most commonly found in Asian and Hispanic populations and is very aggressive. It usually starts in the sinuses or nasal passages. Enteropathy-associated intestinal T-cell lymphoma: Most common in Europeans, this lymphoma starts in the intestines. It may be more likely in those who are intolerant to gluten. Anaplastic large-cell lymphoma: This lymphoma is more likely to be seen in children and younger adults. It can be aggressive but is curable.
Causes
Lymphoma develops when the DNA inside of the T-cell lymphocyte becomes abnormal, and those abnormal cells begin to divide into more abnormal cells. The exact trigger of this change in the DNA is often unknown, but some theories exist.
Lymphocytes are produced in the bone marrow but after release are found throughout the lymphatic system (such as in the lymph nodes and spleen). In lymphoma, cancerous changes start in lymphocytes in the lymphatic system and can spread elsewhere in the body. The cancerous cells generally do not develop in the bloodstream.
There is some overlap in the definitions for some subtypes, such as T-lymphoblastic lymphoma/leukemia and adult T-cell lymphoma/leukemia.
Factors that may be responsible for affecting the DNA of the cells include:
Exposure to ultraviolet (UV) raysChemical exposureRadiation exposureViral infectionsBacterial infectionsStressPoor dietSpontaneousInherited factors
Symptoms
Symptoms differ among the types of lymphoma. Symptoms of T-cell lymphoma can include:
Enlarged lymph nodes Fever Chills Drenching night sweats Frequent infections Itchy skin rash Easy bleeding, bruising Unintentional weight loss Shortness of breath or cough Red or purple bumps on the skin
Diagnosis
The diagnosis of lymphoma often starts with a physical exam from a healthcare provider. During the exam, the provider can evaluate for the presence of any enlarged lymph nodes or other abnormal findings.
Biopsy
A biopsy will determine if cancer is present. During a biopsy, a sample of the suspicious area is removed for testing. Specialized lab testing is performed by a pathologist (a specialist in laboratory medicine) to determine the type of cancer cells present.
Imaging Studies
Imaging studies, such as computerized tomography (CT), positron-emission tomography (PET) scan, magnetic resonance imaging (MRI), or ultrasound, are used to determine the exact location in the body where cancer is located.
When reviewed in combination with the biopsy results, imaging determines the stage of the lymphoma, which defines how far the cancer has spread.
Treatment
Treatment will be determined by the oncologist (specialist in cancer) treating the lymphoma. Treatment is based on the type of T-cell lymphoma and its stage.
Treatment options can include chemotherapy, radiation, monoclonal antibodies, and stem cell transplant. Some forms of T-cell lymphoma, especially if it is slow growing, may not receive any treatment.
Chemotherapy
Chemotherapy is medication that is given to keep cancer cells from continuing to grow. It is typically given in combinations of different medications and is most often given through an intravenous (IV) infusion (through a line into a vein). Other forms of chemotherapy include topical preparations (applied to the skin), pills, or given into the cerebrospinal fluid (intrathecally).
Radiation
Radiation treatment uses high-energy beams to damage the DNA in the cancer cells, which causes cell death and prevents the cells from continuing to grow. Radiation treatments are typically given once a day for a period of a few weeks under the direction of a radiation oncologist.
Monoclonal Antibodies
These infusions may be used alone or in combination with chemotherapy. They work by targeting specific proteins on the outside of cells, which can help recruit the immune system to fight off the cancer.
Stem Cell Transplant
Some T-cell lymphomas require high doses of chemotherapy to kill. In killing the cancer cells, the bone marrow, where blood cells are formed, can be killed off as well.
A stem cell transplant infuses healthy stem cells back into the body to be able to create blood cells again. The stem cells can come from a donor or be removed from the patient before chemotherapy.
Prognosis
The type of T-cell lymphoma that someone is diagnosed with will determine the prognosis (outcomes). However, when looking at T-cell lymphomas overall, the estimated five-year survival rate is 63%. This means that for those diagnosed with T-cell lymphoma, approximately 63% were alive five years after diagnosis.
The five-year survival rate for the lymphoma subtypes varies from over 90% for mycosis fungoides to less than 20% for enteropathy-associated intestinal T-cell lymphoma. New drugs and clinical trials are developed and continue to improve the prognosis of T-cell lymphomas.
These survival rates are of people diagnosed at least five years in the past and do not reflect outcomes with newer treatments. Your individual prognosis will also be influenced by the stage at diagnosis, your overall health, other conditions you have, your age, and more.
You need to have an in-depth discussion with your healthcare provider to understand your treatment options, predicted survival, and the chance of a cure or remission.
Summary
T-cell lymphomas are rare cancers of the T cells in the lymphatic system. Multiple types of T-cell lymphomas exist, with some being aggressive and others being slow growing. Depending on the type and other factors, the condition will be treated with chemotherapy, monoclonal antibodies, or simply by observation alone.
A Word From Verywell
Receiving a diagnosis of T-cell lymphoma can be an anxiety-provoking time. It is important to talk to your healthcare team if you have any questions about your diagnosis, treatment plan, or prognosis, as they will have the most accurate information for you.
