Non-Hodgkin Lymphoma, the third most common childhood cancer and sixth most common adult cancer, occurs in the lymphatic system. It causes the cells in the lymphatic system to abnormally reproduce, eventually causing tumors to grow. Non-Hodgkin lymphoma cells can also spread to other organs. Types There are several types of non-Hodgkin lymphoma, which are classified by how quickly they spread. Risk Factors No specific cause for non-Hodgkin lymphoma has been identified. But there are suggested risk factors for the disease, including the following: older age, immune system deficiency, autoimmune diseases, exposure to radiation, exposure to chemicals such as benzene and herbicides, organ transplantation, infections with human immunodeficiency virus (HIV), infections with the parasite that causes malaria, history of infectious mononucleosis (caused by an infection with the Epstein-Barr virus), and infections with Helicobacter pylori bacterium, which has been identified as a cause of stomach ulcers. Symptoms The symptoms of non-Hodgkin lymphoma may resemble other blood disorders or medical problems, such as influenza or other infections. Unintended weight loss, fatigue, and night sweats are frequently reported. Always consult your doctor for a diagnosis. Diagnostic Procedures To diagnose non-Hodgkin lymphoma, a doctor starts by performing a complete medical history and physical examination. Other procedures used to diagnose non-Hodgkin lymphoma may include the following: Blood tests and other evaluation procedures Chest X-ray—a diagnostic test that uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film Lymph node biopsy—a procedure performed to remove tissue or cells from the body for examination under a microscope. Genetic tests can identify the specific subtype of lymphoma. Bone marrow aspiration and/or biopsy—a procedure that involves taking a small amount of bone marrow fluid (aspiration) and/or solid bone marrow tissue (called a core biopsy), usually from the hip bones, to be examined for the number, size, and maturity of blood cells and/or abnormal cells Computed tomography scan (also called a CT or CAT scan)—a diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce cross-sectional images (often called slices) of the body Ultrasound (also called sonography)—a diagnostic imaging technique that uses high-frequency sound waves and a computer to view internal organs as they function and to assess blood flow through various vessels Positron emission tomography (PET)—a procedure that evaluates the function and structure of a particular organ or tissue, allowing the doctor to identify the onset of a disease before anatomical changes related to the disease can be seen with other imaging procedures, such as a CT Treatment Treatment for non-Hodgkin lymphoma depends on the specific subtype and stage of lymphoma, including how far the disease has spread. Treatment strategies include radiation therapy, conventional chemotherapy, targeted molecular therapy, surgery, biologic (immune) therapy or peripheral blood stem cell transplantation, and high-dose chemotherapy with bone marrow or peripheral blood stem cell transplantation. Your doctor will decide on the specific treatment after reviewing your medical history and other factors.