Superficial spreading melanoma is a type of skin cancer that slowly grows horizontally across the top layer of skin before moving to the deeper layers. It’s the most common form of melanoma, accounting for 70 percent of all cases. While it’s uncommon in children, superficial spreading melanoma can affect people of all ages, even in areas of the body that see little sun.
Superficial spreading melanoma has many identifiable symptoms, including:
- Shape: It can be raised or flat and usually has an irregular shape and borders. It can also look like a freckle that’s growing sideways.
- Color: It may be brown, tan, black, red, blue, and even white. It can also have a combination of these colors.
- Location: It usually appears on the torsos of men, the legs of women, and the upper backs of both sexes. It can also appear in an existing or new mole.
- Changes: It changes slowly, usually over the course of several years.
- Itch: It can sometimes be itchy.
Superficial spreading melanoma sometimes looks like a freckle, which can make it hard to recognize. You can use a system known as the “ABCDEs” of skin cancer to help you identify spots that may be skin cancer:
- Asymmetry: If you draw a line down the center of the skin patch, the two sides won’t match up. One side will be larger than the other.
- Border: The outline of the skin patch will be irregular and jagged if the spot is cancerous.
- Color: Moles and patches that aren’t cancerous are usually brown. Skin cancer can be a range of colors, including red, black, and blue.
- Diameter: Most skin cancers have a diameter that’s larger than a pencil’s eraser.
- Evolving: Cancerous patches change in shape, size, and color over time.
The exact causes of superficial spreading melanoma are unknown, but it seems to be related to environmental factors and genetic mutations.
While anyone can develop superficial spreading melanoma, some are more likely to than others. Things that make you more likely to develop it include:
- Middle age: It tends to occur most often in people in their 40s and 50s.
- Light-colored skin: As with other skin cancers, people with fair skin are most at risk for developing superficial spreading melanoma. This is likely because fair skin has less melanin, a skin pigment that can help protect the skin from harmful UV rays.
- UV exposure: It tends to occur in the back, chest, and legs, which are all likely to get intense, periodic UV exposure from the sun. Getting sunburns at an early age and UV exposure from tanning beds also increase your risk.
- Having a lot of moles: Since many cases develop within moles, the more moles you have, the greater your chance of having superficial spreading melanoma. People with 50 or more moles have a greater risk of melanoma, according to the American Skin Association.
- Family history: While it isn’t inherited, some of the gene mutations responsible for superficial spreading melanoma are. The BRAF gene, which can allow cancer cells to grow freely, may play a role in melanoma.
To diagnose you, your doctor will do a biopsy. This involves taking a tissue sample and seeing it if has cancer cells. Your doctor may also remove some lymph nodes close to the affected area to see if the cancer has spread. This process is known as a sentinel lymph node biopsy. If your doctor thinks that cancer may be spreading, they may also do computed tomography (CT) or magnetic resonance imaging (MRI) scans.
Superficial spreading melanoma is diagnosed by its stage, which reflects how severe it is. Stages 1 and 2 are considered early stages. They respond well to treatment and have the highest rates of recovery. Stages 3 and 4 are more advanced stages and usually mean the cancer has spread to other parts of the body. These advanced stages are harder to treat and have lower rates of recovery.
Stage 1 or 2 superficial spreading melanoma is usually treated with surgery to remove the cancerous cells. Stage 3 or 4 may need additional therapies, such as chemotherapy or radiation.
Another option for more advanced cases is biological therapy, which involves using substances, such as interferon, to help boost the immune system.
Exposure to UV rays is strongly associated with superficial spreading melanoma. The easiest way to reduce your risk is to limit your exposure to UV rays from both the sun and tanning lights and beds.
When you’re in the sun, make sure to apply sunscreen with an SPF of at least 15. Wearing a wide-brimmed hat and covering your skin can also help limit your exposure to UV rays.
According to a recently published study looking at nearly 100,000 people with superficial spreading melanoma, the overall five-year survival rate was 95 percent and rising. That means that 95 percent of people with superficial spreading melanoma were alive five years after being diagnosed. The size, thickness, location, and stage of superficial spreading melanoma all affect survival rates.
Early diagnosis is key in successfully treating superficial spreading melanoma, so make sure to tell you doctor if you notice any unusual spots on your skin.