Cancers go through distinct periods, phases, or stages in their growth. The process of determining the stage of cancer is called "staging." A doctor must know the stage of a cancer in order to pick the most effective treatment. Advanced cancer that has spread needs treatment quite different than localized cancer growing only in the original tumor site.
Skin cancer is "staged" by information obtained from various tests. Doctors usually divide skin cancer into two stages, localized and metastatic.
- Localized skin cancer has not moved beyond the visible tumor. Most skin cancers are diagnosed in this stage. The
biopsyis the only test needed to determine the stage.
- Metastatic cancer has spread beyond the original site. The doctor may suspect that spread has occurred when a skin cancer is unusually large or has been growing for a long time or there are symptoms of internal problems, such as a cough or headache. In such cases, the doctor will examine
lymph nodesin the area for signs of spread. In addition, the doctor may order other tests, such as chest x-rays, MRI, or CT scan, to see if cancer has spread elsewhere in the body.
At first, cancer is restricted, or localized, to one place in the body. Skin cancer diagnosed early usually is growing only in the area of the visible tumor. Later in its life, if untreated, some skin cancers may reach a more advanced stage, spreading to nearby lymph nodes. In the most advanced stage, cancer has spread to other organs in the body.