Lymphoma is a cancer that affects the lymph system, which is a sort of transportation network that carries infection fighting white blood cells throughout the body. Lymphoma presents various symptoms that are frequently mistaken for an infection. The most common symptom a person notices is an enlargement of the lymph nodes in areas of the body ranging from the groin, neck, or armpit area. It is described as a lump. Appetite and weight loss also occur, along with fever, excessive sweating, lethargy, itching and shortness of breath. In addition, other organs can become affected. The spleen could become enlarged, causing stomach pain or an early feeling of fullness. Arms and legs can experience swelling and in some instances tingling and numbness occurs. Two types of lymphoma exist: Non-Hodgkin's and Hodgkin's. The differences occur within the type of lymphocyte cell the cancer derives from. Lymphocytes filter infectious organisms and fight illness. There are two types of lymphocytes: types B and T. Hodgkin's comes from abnormal B lymphocytes. Non-Hodgkin's can derive from abnormal T or B lymphocytes that have distinguishable features that doctors can differentiate between. In order to properly diagnose lymphoma, doctors run a battery of tests so that they can pinpoint the severity, location, stage and prognosis of the cancer. Tests include blood work, x-rays, scans and biopsies. In some cases, bone marrow tests may also be necessary. The various exams help doctors ensure they properly stage the lymphoma. The stages run from I to IV. The letters "A" and "B" are also added to the diagnosis. "A" means no typical symptoms are present; "B" means symptoms are present. Treatment for lymphoma involves the use of chemotherapy and radiation. It varies depending on a person's health and age. Although the causes of any kind of cancer are not specifically known, researchers do know what risk factors are associated with different cancers. Some of the risk factors linked to lymphoma include old age, infections such as HIV, Epstein-Barr virus, H. Pylori, and hepatitis, other diseases that cause the immune system to become weak, genetics, and exposure to some chemicals. In order to improve the possibility of remission, it is important to have yearly physical exams and to see a doctor whenever signs of illness arise. Early detection is key to fighting cancers like lymphoma.