Skin cancer is the abnormal growth of skin cells. It’s a common cancer that can form on any part of the body, but it often occurs on sun-exposed skin.

The sun’s ultraviolet (UV) rays can damage the DNA in your skin cells over time, resulting in the growth of cancerous cells.

Anyone can get skin cancer, but some things can increase a person’s risk. Risk factors include having:

  • lighter skin
  • a history of sunburns
  • a personal or family history of skin cancer

Skin cancer survival rates vary depending on the type of cancer. Some types of skin cancer are life-threatening when not treated early, while others have a low death rate.

The four most common types of skin cancer include:

Melanoma

Melanoma is skin cancer that forms in melanocytes. These are the skin cells that produce melanin, a pigment responsible for skin color.

Melanoma is the most dangerous type of skin cancer, but it’s also a less common type.

Melanoma skin cancer usually presents as a brown or black spot that’s larger than a mole.

The spot or bump can have an irregular border and shades of different colors. The bump might be reddish in color with black, blue, or purple spots mixed in.

Melanoma can develop anywhere on the body, such as the:

  • chest
  • back
  • legs
  • soles of the feet
  • underneath the nails

Basal cell carcinoma

Basal cell carcinoma is the most common type of skin cancer. It accounts for more than 80 percent of skin cancer diagnoses.

It forms in the basal cells and is found on parts of the body heavily exposed to the sun. Although basal cell carcinoma grows slowly and doesn’t usually spread to surrounding areas, it can be life-threatening if left untreated.

Symptoms of basal cell carcinoma include:

  • flat white or yellowish area
  • raised red patches
  • pink or red shiny bumps
  • pink growths with raised edges
  • open sore that doesn’t heal

Squamous cell carcinoma

Squamous cell carcinoma also has a low death rate. It’s slow-growing and can develop on the:

  • face
  • neck
  • back
  • chest
  • ears
  • back of the hands

Symptoms include:

  • rough, scaly red patches
  • raised bumps or lumps with a slight indentation in the center
  • open sores that don’t heal
  • wartlike growths

Merkel cell carcinoma

Merkel cell carcinoma starts in the Merkel cells. These are located below the top layer of skin near the nerve endings.

It’s an aggressive type of skin cancer that’s difficult to treat, but it’s rare. It’s more likely to occur in people older than 50 and those with a weaker immune system.

Merkel cell carcinoma is fatal if it spreads to the brain, lungs, liver, or bones.

An early sign of Merkel cell carcinoma is a fast-growing flesh-colored bump or nodule that may bleed. Nodules can also be red, blue, or purple.

If you receive a skin cancer diagnosis, the next step is to identify its stage.

Staging is how doctors determine whether the cancer has spread to other parts of your body. Staging is common with melanoma and Merkel cell carcinoma, because these cancers are more likely to spread.

Typically, basal cell and squamous cell carcinomas don’t involve staging. These skin cancers are easily treated and don’t usually spread. However, your doctor may recommend staging for larger lesions.

Staging is based on the size of the growth and whether it has high-risk features. High-risk features include:

  • larger than 2 millimeters thick
  • spreads into the lower levels of the skin
  • spreads into the space around a nerve
  • appears on the lips or ears
  • appears abnormal under a microscope

Here’s a general breakdown of skin cancer stages:

  • Stage 0. The cancer hasn’t spread to surrounding areas of the skin.
  • Stage 1. The cancer is 2 centimeters (cm) across or less, with no high-risk features.
  • Stage 2. The cancer is more than 2 cm across and has a least two high-risk features.
  • Stage 3. The cancer has spread to the bones in the face or nearby lymph nodes.
  • Stage 4. The cancer has spread to the lymph nodes or internal organs.

The outlook, or survival rate, for skin cancer depends on the type of skin cancer and stage of cancer at diagnosis.

Typically, the earlier you receive a diagnosis with skin cancer, the better your outcome. Cancer is harder to treat once it spreads to other parts of the body.

Melanoma survival rate

Melanoma is a deadly cancer when it spreads, but it’s curable in its early stages.

The five-year survival rate for melanoma stages 0, 1, and 2 is 98.4 percent, according to the Melanoma Research Alliance.

The five-year survival rate of stage 3 melanoma is 63.6 percent. It’s 22.5 percent for stage 4 melanoma.

Merkel cell survival rate

According to the American Cancer Society, the five-year survival rate for Merkel cell stages 0, 1, and 2 is 78 percent. It’s 51 percent for stage 3 and 17 percent for stage 4.

Basal cell and squamous cell survival rates

Because basal cell and squamous cell carcinomas are lower-risk skin cancers, there’s little information on survival rates based on stage.

Both types of cancer have a very high cure rate. According to the Canadian Cancer Society, the five-year survival rate for basal cell carcinoma is 100 percent. The five-year survival rate for squamous cell carcinoma is 95 percent.

Skin cancer is a very preventable cancer. Here’s how to protect yourself when outdoors:

  • Use sunscreen with an SPF of at least 30 or higher. Follow product instructions and reapply as needed.
  • Wear sunglasses.
  • Wear a wide-brimmed hat to protect your face, head, ears, and neck.
  • Wear pants and long sleeves to protect your arms and legs.
  • Stay in the shade when possible.
  • Avoid indoor tanning.
  • Avoid the sun during the middle of the day when it’s at its strongest.
  • Tell your doctor of any new skin growths or changes to moles, bumps, or birthmarks.

Once a skin biopsy confirms skin cancer, your doctor will recommend a treatment based on the stage of the cancer.

To improve your outlook, it’s important that you complete your treatment and schedule follow-up appointments as needed. Your doctor may want to see you every few months to make sure the cancer hasn’t returned.

Also schedule annual skin exams with a dermatologist. Get into the habit of checking your own skin for abnormal growths, too. This includes your back, scalp, soles of feet, and ears.

You can also ask your doctor about local support groups for those with skin cancer, or search for support programs in your area.

Depending on the type, skin cancer can grow rapidly and become life-threatening if not treated early.

Talk to your doctor if you have any new growths on your skin or notice changes to an existing mole, bump, or birthmark.

Skin cancer has a high cure rate, but only if caught early.