Key points There are five stages of melanoma ranging from stage 0 to stage 4.

Survival rates are just estimates and don’t ultimately determine an individual’s specific prognosis.

Early diagnosis greatly increases survival rates.

What is melanoma? Melanoma is a kind of cancer that begins in the skin cells that create the pigment melanin. Melanoma usually starts as a dark mole on the skin. However, it can also form in other tissue, such as the eye or mouth. It’s important to keep an eye on moles and changes in your skin, as melanoma can be deadly if it spreads. There were more than 10,000 deaths from melanoma in the United States in 2016.

How is melanoma staged? Melanoma stages are assigned using the TNM system. The stage of the disease indicates how much the cancer has progressed by taking into account the size of the tumor, whether it’s spread to lymph nodes, and whether it’s spread to other parts of the body. A doctor can identify a possible melanoma during a physical exam and confirm the diagnosis with a biopsy, where the tissue is removed to determine if it’s cancerous. But more sophisticated technology, such as PET scans and sentinel lymph node biopsies, are necessary to determine the cancer’s stage or how far it’s progressed. There are five stages of melanoma. The first stage is called stage 0, or melanoma in situ. The last stage is called stage 4. Survival rates decrease with later stages of melanoma. It’s important to note that survival rates for each stage are just estimates. Each person with melanoma is different, and your outlook can vary based on a number of different factors.

Stage 0 Stage 0 melanoma is also called melanoma in situ. This means that your body has some abnormal melanocytes. Melanocytes are the cells that produce melanin, which is the substance that adds pigment to the skin. At this point, the cells could become cancerous, but they’re simply abnormal cells in the top layer of your skin. Melanoma in situ may look like a small mole. Even though they may appear harmless, any new or suspicious-looking marks on your skin should be evaluated by a dermatologist.

Stage 1 In stage , the tumor is up to 2 mm thick. It may or may be ulcerated, which indicates whether the tumor has broken through the skin. The cancer has not spread to nearby lymph nodes or to distant parts of the body. For stage 0 and stage 1, surgery is the main treatment. For stage 1, a sentinel node biopsy may be recommended in some cases.

Stage 2 Stage 2 melanoma means the tumor is more than 1 mm thick and may be larger or have grown deeper into the skin. It may be ulcerated or not ulcerated. The cancer has not spread to nearby lymph nodes or to distant parts of the body. Surgery to remove the cancerous tumor is the usual treatment strategy. A doctor may also order a sentinel lymph node biopsy to determine the cancer’s progression.

Stage 3 At this point, the tumor may be smaller or larger. In stage 3 melanoma, the cancer has spread to the lymph system. It has not spread to distant parts of the body. Surgery to remove cancerous tissue and lymph nodes is possible. Radiation therapy and treatment with other powerful medications are also common stage 3 treatments.

Stage 4 Stage 4 melanoma means the cancer has spread to other parts of the body, such as the lungs, brain, or other organs and tissue. It may have also spread to lymph nodes that are a good distance from the original tumor. Stage 4 melanoma is often hard to cure with current treatments. Surgery, radiation, immunotherapy, targeted therapy and chemotherapy are options for treating stage 4 melanoma. A clinical trial may also be recommended.

Survival rates The 5-year survival rates for melanoma, according to the American Cancer Society are: Local (cancer has not spread beyond where it started): 99 percent

Regional (cancer has spread nearby/to the lymph nodes): 65 percent

Distant (cancer has spread to other parts of the body): 25 percent The 5-year survival rate reflects patients who lived at least 5 years after being diagnosed. Factors that could affect survival rates are: new developments in cancer treatment

a person’s individual characteristics and overall health

a person’s response to treatment