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 intestine.
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 9,000 deaths from melanoma in the United States in 2013.
How melanoma is staged
Melanoma is described by stages. A particular stage of the disease gives an idea how far the cancer has spread. Early on, a physical exam is usually enough to identify stage 1 melanoma, for example. But more sophisticated technology, such as PET scans and sentinel lymph node biopsies, are necessary to measure the cancer’s progression.
Essentially, 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 tend to go down at each stage 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 melanoma is also called melanoma in situ. This means is that your body has some abnormal melanocytes. Melanocytes are the cells that produce melanin. This 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.
In stage 1A, the tumor is up to 1 millimeter (mm) thick. It also has no ulceration, which means the tumor hasn’t broken through the skin. Stage 1B can means two things: the tumor is up to 1 mm thick and has some ulceration, or it’s between 1 mm and 2 mm thick and has no ulceration.
The five-year survival rate for stage 1A is 97 percent and 92 percent for stage 1B. The 10-year survival rates are 95 percent for stage 1A and 86 percent for stage 1B, according to the American Cancer Society.
Stage 2 melanoma means the tumor has grown more than 2 mm thick. Doctors will also analyze the tumor to see if it’s ulcerated. 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.
The five-year survival rate for stage 2A is 81 percent and 70 percent for stage 2B. The 10-year survival rates are 67 percent for stage 2A and 57 percent for stage 2B, according to the American Cancer Society.
At this point, the tumor can be any size or shape. To be considered stage 3 melanoma, the cancer has to have spread to the lymph system. Surgery to remove cancerous tissue and lymph nodes is possible. Radiation therapy and treatment with other powerful medications are also common stage 3 treatments.
The American Cancer Society reports the five-year survival rate for stage 3 melanoma ranges from 40 to 78 percent. The 10-year survival rate ranges from 24 to 68 percent.
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. As such, stage 4 melanoma is often hard to cure with current treatments.
The five-year survival rate is only about 15 to 20 percent. The 10-year survival rate is 10 to 15 percent, according to the American Cancer Society.
Factors affecting survival rates
The five- and 10-year survival rates for the various stages of melanoma are based on patients who lived at least five or 10 years after being diagnosed.
Factors that could affect survival rates are:
- new developments in cancer treatment
- a person’s response to treatment
- age (older patients tend not to live as long at each stage of the disease)
See your doctor
In its early stages, melanoma is a treatable condition. But the cancer must be identified and treated swiftly.
If you ever see a new mole or a suspicious mark on your skin, promptly have it evaluated by a dermatologist. If your immune system is weakened by a condition such as HIV, getting checked is especially important.
One of the best ways to avoid developing skin cancer is to wear protective sunscreen all the time. Wearing clothes that protect against the sun, such as sun-block shirts, is also helpful.
Be sure to familiarize yourself with the ABCDE method, which can help you determine whether a mole is potentially cancerous.