Staging is then done based on the Ann Arbor Staging Classification:
• Stage I indicates that the cancer is located in a single region, usually one lymph node and the surrounding area. Stage I will often not have obvious, outward symptoms.
• Stage II indicates that the cancer is located in two separate lymph node regions, and that both areas are on the same side of the diaphragm (the muscle located at the bottom of the lungs) - that is, both are above the diaphragm or both are below the diaphragm.
• Stage III indicates that the cancer involves lymph nodes or organs on both sides of the diaphragm.
• Stage IV : Either of the following means that the disease is stage IV
Cancer has spread to multiple spots of an organ (or multiple organs) outside the lymph system. Cancer cells may or may not be found in the lymph nodes near these organs.
Cancer has spread to only one organ outside the lymph system, but lymph nodes far away from that organ are involved.
These letters can be added to all stages: (ex: stage IIA, stage IIIB)
• A : No symptoms
• B : Presence of "B symptoms" (fever, night sweats, weight loss > 10% of body weight)
• E: is used if the disease is "extranodal" (not in the lymph nodes) or has spread from lymph nodes to adjacent tissue.
• X : is used if the largest tumor is >10 cm large (also called "bulky disease"), or whether the lymph node in the center of the chest (mediastinal node) is wider than 1/3 of the chest on a chest X-ray.
