Lymphoma: diagnosis and treatment

What is lymphoma?
Lymphoma is a kind of blood cancer arising from white blood cells or lymphocytes. Normally the blood has three components I.e red cells which carry hemoglobin and oxygen, platelets which help in formation of blood clots and white blood cells that fight infections. Lymphocytes are a type of white blood cells that give us immunity and lymphoma is a cancer of these lymphocytes.
What are the signs and symptoms of lymphoma?