Staging (definition of)

Staging refers to the element of a diagnosis in which it is determined how far a disease has progressed.

Oncology recognizes four stages of mesothelioma, which is either localized or advanced. There are also a few different staging systems, but all follow the same general characteristics.

In Stage I, the disease is found only on the surface of the mesothelium, the thin membrane covering the lungs, inner chest and abdominal wall and other internal organs. At this stage, mesothelioma is still localized and can be removed surgically. However, in order to prevent recurrence followup treatments with medications may be necessary.

In Stage II, mesothelioma has spread to the lymph nodes on the side of the body in which the cancer first appeared.

By Stage III, mesothelioma has spread into the mediastinum, which includes the trachea (windpipe) and the esophagus (food passage), the thymus and the heart. Cancer is also found in the lymph nodes on the opposite side of the chest and the lining of the abdominal wall.

By Stage IV, the patient is terminal; the cancer has metastasized to distant parts of the body. By this point, all that can be offered are palliative (pain-relieving) treatments.

Staging is a necessary in order to determine the proper course of treatment. Surgery may be effective in Stage I and in some cases even Stage II, but the later stages require chemotherapy and radiation treatments as well as surgical removal of part of the lung and diaphragm in order to relieve the pressure caused by fluid build-up in the chest cavity in many cases.