Non-Hodgkin’s lymphoma is a cancer that rises in the cells of the lymphatic system, especially in T lymphocytes (T cells) or b-lymphocytes (B –cells). Therefore, Non-Hodgkin’s lymphoma can be divided in two main groups: T–cell lymphomas or B -cell lymphomas. The incidence of each type varies according to geographic area. The B-cell lymphomas account for 75% of cases of non-Hodgkin’s lymphoma in Western countries; T-cell lymphomas, in the other hand, are more common in Eastern Asia countries.
B-cell non-Hodgkin lymphomas include many subtypes:
- Burkitt lymphoma
- follicular lymphoma
- immunoblastic large cell lymphoma
- precursor B-lymphoblastic lymphoma
- mantle cell lymphoma
- diffuse large B-cell lymphoma
- Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL).
Common subtypes of T-cell non-Hodgkin lymphomas include:
- mycosis fungoides
- anaplastic large cell lymphoma
- Precursor T-lymphoblastic lymphoma.
The lymphatic system comprises a network of lymphatic vessels (also called ducts) that ensure the circulation and cleansing of the lymph from bacteria, microscopic waste, and unwanted cells including cancer cells. The lymphatic system also includes all organs where there are large quantities of white blood cells: the lymph nodes, bone marrow, spleen, thymus, and the mucosa-associated lymphoid tissues which include the digestive tract, lungs, skin, etc. the main role of the lymphatic system is to protect the body against certain microorganisms, tissues and foreign bodies, infections and various pathogenic attacks.