Lymphoma is cancer of the lymphatic system. The lymphatic system consists of lymph nodes present all over the body, the lymph vessels that connect these lymph nodes with each other. Organs such as the spleen, thymus gland, bone marrow and tonsils are also part of the lymphatic system. Lymphocytes, which are white blood cells present in the blood and bone marrow are also part of the lymphatic system.
The function of the lymphatic system is to drain fluid from the organs and to protect the body from infections. When the infection is present in a part of the body, the lymph nodes in that area try and stop the infection from spreading to other parts of the body. This can lead to enlargement of the lymph nodes as seen commonly.
There are two main types of lymphoma. One is called as Hodgkins lymphoma and the other one is called as Non Hodgkins Lymphoma.
Non-Hodgkin lymphomas make up about 80% of all lymphomas. They do not contain Reed Sternberg cells when seen under the microscope. These lymphomas can again be divided into a number of subtypes depending on their appearance when seen under the microscope. They are also classified into low grade, intermediate grade and high grade Non-Hodgkin lymphoma (NHL).
Non-Hodgkin lymphoma can be of many types. Based on the cell of origin, they can broadly be classified into
- T Cell Lymphomas
- B Cell lymphomas
They can also be classified based on how they appear when seen under the microscope.
The common varieties seen are-
- Diffuse large B cell Lymphoma
- Mantle cell lymphoma
- Burkitt cell lymphoma
- Follicular lymphoma
- Lymphoplasmacytic lymphoma
- Small lymphocytic lymphoma/Chronic lymphocytic lymphoma
- Marginal zone lymphoma
- NK and T cell lymphoma
According to Globocan data 2018, there were 28,110 new non-Hodgkin lymphoma cancers in India in 2018, making up 2.4% of all cancers.