Lymphoma is a group of blood cancers that develop from lymphocytes (a type of white blood cell). The name often refers to the cancer versions rather than all of these tumors. Signs and symptoms may include enlarged lymph nodes, fever, profuse sweating, involuntary weight loss, itching, and tiredness of a constant feeling. The enlarged lymph nodes are mostly painless.  Sweats are the most common at night.  There are many subtypes of lymphomas.  The two main categories of lymphomas are non-Hodgkin's lymphoma (NHL) (90% of cases) and Hodgkin's lymphoma (HL) (10%).  The World Health Organization (WHO) includes two other categories of lymphoma types: multiple myeloma and immunoproliferative diseases. About 90% of lymphomas are non-Hodgkin's lymphomas Lymphomas and leukemias are part of a larger group of hematopoietic and lymphoid tissue tumors.

Risk factors for Hodgkin's lymphoma include infection with the Epstein-Barr virus and a family history of the disease. Common types of risk factors for non-Hodgkin's lymphoma include autoimmune disease, HIV / AIDS, human T-lymphotropic virus infection, immunosuppressive drugs, and certain pesticides. Eating is the biggest risk of red meat and tobacco. The diagnosis, if enlarged lymph nodes are present, is largely made by biopsy of the lymph nodes. Blood, urine and bone marrow tests can also be helpful in diagnosis. Medical imaging can then be done if and where the cancer has spread. Lymphoma most frequently spreads to the lungs, liver and brain