• There are many different types of lymphoma but they are broadly divided into 2 main groups depending on the appearance (morphology) of their cancerous (malignant) cells.
• These are known as :

• Hodgkin's lymphoma (also called Hodgkin’s disease)

1. Named for Thomas Hodgkin, an English scholar and physician, who first described it in 1832.
2. This form is more common in older children or teenagers than children younger than 5 years old.
3. This type of lymphoma is defined by the presence of specific malignant cells, called Reed-Sternberg cells, in the lymph nodes or organ involved.

• Non-Hodgkin's lymphoma.

1. This name applies to all other forms of lymphoma.
2. Non-Hodgkin's lymphomas are seen in all age groups but are more common in older people over 50 years
3. In non-Hodgkin's lymphoma, there is malignant growth of specific types of lymphocytes (a kind of white blood cell found in the lymph nodes).
4. Malignant growth of lymphocytes is also seen in one of the forms of leukemia (acute lymphoblastic leukemia, or ALL), which sometimes makes it difficult to distinguish between lymphoma and leukemia.
5. In general, people with lymphoma have variable bone marrow involvement ranging from no or only minimal to extensive bone marrow involvement, whereas those with leukemia have extensive bone marrow involvement from the outset.

• Both types of lymphoma develop from the lymphatic system. But they affect the body differently, spread differently and respond differently to treatment.
• Hodgkin's and non-Hodgkin's lymphoma are further divided into subtypes based on the specific type of cell affected, the level of maturity reached by the cells, their appearance under a microscope or the way they grow.

Updated:: 04/04/2019 []