Lymphoma is a group of cancers that involves white blood cells of the immune system, called lymphocytes, that begin multiplying and growing at an accelerated rate unchecked, until eventually, a tumor develops. Lymphomas originate in the lymphatic system; that is, a network of specialized vessels which contain lymph fluid and lymphocytes. This system is distributed throughout the body in a channel-like fashion to lymph nodes and other regions, for example, the spleen and bone marrow. The vastness of this system makes the staging critical because staging attempts to specify the extent of malignant spread throughout the body.
Stages I and II
A salient component of the diagnosis process, additionally, is to determine if the disease has spread from its original site to other sites, that is, to specify how widespread or advanced the disease is throughout the body. This is the purpose of staging, which then also provides information as to a patient's potential prognosis, recovery, and survival. Moreover, staging directs the course of treatment, be it surgery, radiation or chemotherapy. Stages are represented by Roman numerals.
Stage I indicates that lymphoma is in one lymph node group only, for example, nodes in the neck or groin. Stage I can also refer to lymphoma that is not in a lymph node group, but instead, is a single organ outside of the lymphatic system; however, the organ excludes the bone marrow or liver at this stage. Stage II indicates progressive disease and uses the diaphragm (muscle separating chest and abdominal cavities) as a marker. Specifically, 2 or more groups of lymph nodes located on the same side (north or south) of the diaphragm are involved, or the disease process now has spread from a node group to a proximal organ. Refer to "Staging Image" in the Reference section below.
Stage III
In the third stage, disease progression becomes more widespread in that now structures on both sides of the diaphragm are involved, that is, lymph node groups on both sides of the diaphragm. Or the case may be that lymphoma now is in an organ adjacent to the lymph nodes. Malignant spread to the spleen also indicates Stage III process.
Stage IV
Llymphoma now is in an organ outside of the lymphatic system, which indicates widespread process because the affected organ is not near an involved lymph node. Or, the malignant process is in the bone marrow or liver, as well as the brain or lining of the lungs. Again, the spread in this stage refers to disease on both sides of the diaphragm marker.
