After confirming a NHL diagnosis, the doctor needs to know the stage, or extent, of the disease to plan the best treatment. Staging is used to find out whether the cancer has spread, and if so, to which parts of the body.
The Ann Arbor Staging System is the system most commonly used by health care providers to describe the extent of non-Hodgkin lymphoma in adults. Stages are classified as Roman numerals I-IV (1-4). A higher number indicates a more advanced disease. Letters added to the staging classification provide additional information on the diagnosis.
- Stage I: The disease is found in only one lymph node or in a lymphoid organ such as the thymus gland (I). A lymphoma can be classified as stage IE (extranodal) when it is found in one area of a single organ not involved in the lymph system (i.e., lung, liver, bone, etc.).
- Stage II: The disease is found in two or more lymph node areas on the same side of the muscle beneath the lungs that separates the chest and abdomen (diaphragm) (IIE), or the cancer has spread locally to a nearby organ next to the lymph nodes (IIE).
- Stage III: The disease is found in lymph nodes on both sides of the diaphragm (above and below it) (III), and has also spread to nearby organs (IIIE), to the spleen (IIIS) or to both (IIIES).
- Stage IV: The disease has spread widely through one or more organs outside of the lymph system, such as liver, bone marrow, or lung; it is found in organs in two distant parts of the body and not in nearby lymph nodes; or it is diagnosed in the liver, bone marrow, lungs or cerebrospinal fluid (the liquid that surrounds the brain and spinal cord).
In addition, letters can be assigned to the stages. These are additional ways to categorize the disease.
- Letter "A" - Added if the symptoms known as “B” symptoms (listed below) caused by NHL are not present.
- Letter "B" - Added if these symptoms are present: a loss of more than 10 percent of body weight over six months (without dieting or over-exercising), a fever of 100.4°F (38 degrees Celsius) or greater without any known cause, and/or drenching night sweats.
- Letter "E" - Added to the stage and indicates that NHL has affected an organ outside of the lymph system but is present next to an affected lymph node.
- Letter "S" - Added to the stage, indicates that NHL is affecting the spleen.
- Letter "X" - The tumor measures at least 10 centimeters across (about 4 inches), which may require more intense treatment. The addition of the letter “X” indicates that the tumor is “bulky”.
NHL is different from HL in that doctors also use the International Prognostic Index (IPI) score. The index depends on 5 factors and is used for aggressive NHL lymphomas. The 5 factors include: the person’s age, the stage of lymphoma, the external involvement of organs present, the patient’s overall health and ability to perform normal activities of daily living, and the LDH level in the person’s blood. The total number of points helps predict the risk of disease relapse.