Key Points
                    - After adult non-Hodgkin lymphoma has been diagnosed, tests are done to find out if cancer cells have spread within the lymph system or to other parts of the body.     - There are three ways that cancer spreads in the body.    - Stages of adult non-Hodgkin lymphoma may include E and S.    - The following stages are used for adult non-Hodgkin lymphoma:         - Stage I     - Stage II     - Stage III     - Stage IV        - Adult non-Hodgkin lymphomas may be grouped for treatment according to whether the cancer is indolent or aggressive and whether affected lymph nodes are next to each other in the body.
                
                
                    After adult non-Hodgkin lymphoma has been diagnosed, tests are done to find out if cancer cells have spread within the lymph system or to other parts of the body.
                    The process used to find out the type of cancer and if cancer cells have spread within the lymph system or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage of the disease in order to plan treatment. The results of the tests and procedures done to diagnose non-Hodgkin lymphoma are used to help make decisions about treatment.   The following tests and procedures may also be used in the staging process:         -   Complete blood count (CBC) with differential : A procedure in which a sample of blood is drawn and checked for the following:               -  The number of red blood cells and platelets.      - The number and type of white blood cells.      - The amount of hemoglobin (the protein that carries oxygen) in the red blood cells.      - The portion of the blood sample made up of red blood cells.              -   Blood chemistry studies : A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease.    -   CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, such as the lung, lymph nodes, and liver, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.    -   PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.     -   MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).     -   Bone marrow aspiration and biopsy : The removal of bone marrow and a small piece of bone by inserting a needle into the hipbone or breastbone. A pathologist views the bone marrow and bone under a microscope to look for signs of cancer.    -   Lumbar puncture : A procedure used to collect cerebrospinal fluid (CSF) from the spinal column. This is done by placing a needle between two bones in the spine and into the CSF around the spinal cord and removing a sample of the fluid. The sample of CSF is checked under a microscope for signs that the cancer has spread to the brain and spinal cord. This procedure is also called an LP or spinal tap.         For pregnant women with non-Hodgkin lymphoma, staging tests and procedures that protect the baby from the harms of radiation are used. These tests and procedures include MRI, bone marrow aspiration and biopsy, lumbar puncture, and ultrasound. An ultrasound exam is a procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram.
                
                
                    There are three ways that cancer spreads in the body.
                    Cancer can spread through tissue, the lymph system, and the blood:         - Tissue. The cancer spreads from where it began by growing into nearby areas.     - Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.     - Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.
                
                
                    Stages of adult non-Hodgkin lymphoma may include E and S.
                    Adult non-Hodgkin lymphoma may be described as follows:         - E: "E" stands for extranodal and means the cancer is found in an area or organ other than the lymph nodes or has spread to tissues beyond, but near, the major lymphatic areas.    - S: "S" stands for spleen and means the cancer is found in the spleen.
                
                
                    The following stages are used for adult non-Hodgkin lymphoma:
                    Stage I      Stage I adult non-Hodgkin lymphoma is divided into stage I and stage IE.            -  Stage I: Cancer is found in one lymphatic area (lymph node group, tonsils and nearby tissue, thymus, or spleen).     -  Stage IE: Cancer is found in one organ or area outside the lymph nodes.              Stage II     Stage II adult non-Hodgkin lymphoma is divided into stage II and stage IIE.            -  Stage II: Cancer is found in two or more lymph node groups either above or below the diaphragm (the thin muscle below the lungs that helps breathing and separates the chest from the abdomen).     -  Stage IIE: Cancer is found in one or more lymph node groups either above or below the diaphragm. Cancer is also found outside the lymph nodes in one organ or area on the same side of the diaphragm as the affected lymph nodes.              Stage III      Stage III adult non-Hodgkin lymphoma is divided into stage III, stage IIIE, stage IIIS, and stage IIIE+S.            -  Stage III: Cancer is found in lymph node groups above and below the diaphragm (the thin muscle below the lungs that helps breathing and separates the chest from the abdomen).     -  Stage IIIE: Cancer is found in lymph node groups above and below the diaphragm and outside the lymph nodes in a nearby organ or area.     -  Stage IIIS: Cancer is found in lymph node groups above and below the diaphragm, and in the spleen.     -  Stage IIIE+S: Cancer is found in lymph node groups above and below the diaphragm, outside the lymph nodes in a nearby organ or area, and in the spleen.              Stage IV     In stage IV adult non-Hodgkin lymphoma, the cancer:             - is found throughout one or more organs that are not part of a lymphatic area (lymph node group, tonsils and nearby tissue, thymus, or spleen), and may be in lymph nodes near those organs; or     - is found in one organ that is not part of a lymphatic area and has spread to organs or lymph nodes far away from that organ; or     - is found in the liver, bone marrow, cerebrospinal fluid (CSF), or lungs (other than cancer that has spread to the lungs from nearby areas).
                
                
                    Adult non-Hodgkin lymphomas may be grouped for treatment according to whether the cancer is indolent or aggressive and whether affected lymph nodes are next to each other in the body.
                    See the General Information section for more information on the types of indolent (slow-growing) and aggressive (fast-growing) non-Hodgkin lymphoma.   Non-Hodgkin lymphoma can also be described as contiguous or noncontiguous:         -  Contiguous lymphomas: Lymphomas in which the lymph nodes with cancer are next to each other.    -  Noncontiguous lymphomas: Lymphomas in which the lymph nodes with cancer are not next to each other, but are on the same side of the diaphragm.