T-cell lymphoma are infrequent neoplasias and represent approximately 10% of all Non-Hodgkin Lymphoma (NHL). With an incidence of around 1.7 per every 100,000 inhabitants/year, it varies depending on the countries, with greater prevalence in Asia. The incidence of this disease has been increasing in recent years, which is arousing interest in discovering the reasons for said increase. Among the different entities of lymphoma, the World Health Organisation highlights peripheral T-cell lymphoma, cutaneous T-cell lymphoma, lymphoblastic and anaplastic lymphoma. Some of these cancers are, however, extremely rare. There are many studies that suggest that T-cell lymphomas have a worse prognosis; nevertheless, although some types, such as peripheral T-cell lymphomas, show a worse prognosis, in others, such as anaplastic, the prognosis is better.
- Peripheral T-cell lymphoma is a rare variety and is more frequent in Asia, due to the fact that it is related to the HTLV-1 virus (human T-cell leukaemia virus).
- Cutaneous T-cell lymphoma represents 2% of all cases of Non-Hodgkin Lymphoma and it is more frequent in adults. It may go unnoticed for years as the symptoms are very similar to eczema or psoriasis.
- Anaplastic lymphoma may appear on the skin, the same as with cutaneous lymphoma, but also in other organs. Prognosis is excellent if treated with radiotherapy, chemotherapy and, sometimes, surgery.
- Lymphoblastic lymphoma is more frequent in children and, fortunately, its rate of complete remission with chemotherapy is as high as 96% in most cases.
Risk factors
Lymphomas occur due to damage in the DNA or genetic material of the lymphocytes or immune system cells which alters the behaviour of said cells. This defect causes an anomalous production of the proteins involved in the prevention of cell death and/or causes accelerated cell division. These malignant cells are capable of developing tumours in the lymphatic glands, skin or mucosa.
The aetiology is unknown although it is associated to genetic predisposition with certain factors: exposure to certain viruses such as HTLV-1, Epstein-Barr disease, HIV and the Hepatitis C Virus (HCV); chromosome alterations due to translocation of the genetic material, and exposure to toxic substances such as benzene, radiation and pollution.
Prevention
There are no tests for the early detection of lymphomas or external conditioning factors related to lifestyle habits which influence the appearance of lymphoma; its appearance, therefore, can not be prevented. Secondary prevention is recommended, going to the doctor as soon as possible when there is inflammation of the lymph glands, since many lymphoma are curable and, in many other cases, the available treatments are effective and achieve long survivals with a good quality of life.
Signs and symptoms
The initial symptoms of a lymphoma are: inflammation in the lymph glands of the upper trunk; shivering/fever; inexplicable weight loss; loss of appetite; unusual fatigue and lack of energy; breathing difficulties; persistent itching over the whole body without apparent cause; general fatigue; inflamed tonsils, and headaches.
In the more advanced phases of lymphoma, generalised symptoms may occur which can be confused with flu, tuberculosis or other infections such as glandular disease or other cancers.
Diagnosis
Most T-cell lymphomas are diagnosed by an adenopathy biopsy. However, many types of T-cell lymphoma are difficult to identify using this symptom, which makes other methods necessary.
Treatment
Since there are multiple varieties of T-cell lymphomas, there are different treatments. Standard therapy for lymphoma is usually effective: chemotherapy, radiotherapy, bone marrow transplant and surgery. Chemotherapy is effective in peripheral T-cell lymphoma, whilst therapy with ultraviolet radiation or electron rays are effective in cutaneous T-cell lymphoma.
Chemotherapy is the main treatment for most lymphomas. Its efficacy and aggressiveness depends on the type of lymphoma and the objective of the treatment (curative or palliative); in aggressive lymphoma, treatment may be curative for which purpose more aggressive chemotherapy schemes are used, whilst in indolent lymphomas, the therapy is not usually curative so the aggressiveness to be used is less, although it may vary from patient to patient.