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 most commonly used 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 stage provide more information about the diagnosis. Although most lymphomas are stage III or IV when diagnosed, they are often still very treatable and possibly curable, even though they have spread across the body.
- Stage I: The disease is found in only one lymph node or in an organ that is part of the lymphatic system, 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 that is not part of the lymph system (such as lung, liver or bone).
- Stage II: The disease is found in two or more lymph node areas on the same side of the diaphragm (the sheet of muscle underneath the lungs) (IIE). Or the cancer has spread 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 to provide more information about the disease:
- Letter "A" - The symptoms known as “B” symptoms (listed below) caused by NHL are not present.
- Letter "B" - 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" - NHL has affected an organ outside of the lymph system but is present next to an affected lymph node.
- Letter "S" - 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.”
Doctors also use the International Prognostic Index (IPI) score to help them better estimate a patient’s outcome. The index was developed to determine the outlook for people with fast-growing (aggressive) NHL lymphomas. It is now used for many other lymphomas.
The index includes 5 factors:
- The person’s age
- The stage of lymphoma
- Whether there is involvement of non-lymph system organs
- The patient’s overall health and ability to perform normal activities of daily living
- The level of the enzyme LDH in the person’s blood. LDH levels are often higher in patients with lymphomas.
The total number of points helps predict the risk of disease relapse.