When skin cells reproduce atypically or too quickly, they can become cancerous. Melanoma is one specific type of skin cancer.

Skin cancer is the most common type of cancer in the United States. Melanoma is a particularly aggressive form of this disease. It quickly spreads from the skin to other body parts, such as the lymph nodes, lungs, and brain.

Melanoma is less common than other types of skin cancer, such as squamous cell carcinoma and basal cell carcinoma.

This article outlines the differences between melanoma and other types of skin cancer.

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Doctors generally divide skin cancer into melanoma and nonmelanoma skin cancer (NMSC).

Melanoma

This is the most aggressive type of skin cancer. It develops in the cells that produce skin pigmentation, known as melanocytes.

Melanoma is rare and develops in 1% of people with skin cancer, according to the American Cancer Society. However, it causes most skin cancer deaths due to its severity.

Nonmelanoma skin cancers

Other types of skin cancer include:

  • Basal cell carcinoma (BCC): This is the most common form of skin cancer. BCC grows slowly and rarely spreads from the original site where it occurred.
  • Squamous cell carcinoma (SCC): This is another common type of skin cancer. It grows slowly in most people but can spread faster in those with compromised immune systems.
  • Merkel cell carcinoma (MCC): MCC is rare but aggressive, with only around 3,000 MCC diagnoses occurring in the United States annually. It often spreads from the skin to other body parts and returns after treatment.
  • Dermatofibrosarcoma protuberans (DFSP): DFSP is a rare, slow-growing cancer that starts in the skin’s middle layer. It rarely spreads and has a high survival rate.
  • Sebaceous carcinoma: This form of skin cancer develops in the skin glands that produce oil. It is rare but easily spreads to other body parts.

Different types of skin cancer can cause different symptoms. However, the signs often involve skin changes that may or may not cause pain, itching, and discomfort.

Melanoma

An early melanoma may resemble a mole, making regular examinations an important part of early detection.

The American Academy of Dermatology (AAD) recommends using the “ABCDEs” of melanoma to spot potentially cancerous moles:

  • Asymmetry: The sides of the spot or mole appear different from one another.
  • Border: The spot has an irregular or poorly defined border.
  • Color: Different areas of the spot have different colors. For example, they may be different shades of tan, brown, black, white, red, or blue.
  • Diameter: Melanomas are often more than 6 millimeters in diameter, although they can be smaller. This is equivalent to a pencil eraser or pea.
  • Evolving:The spot may change size, shape, or color over time.

Nonmelanoma skin cancer

People often first notice NMSC after they spot a red or discolored, firm lump or flat, scaly patch on the skin that has not healed after several weeks.

Other symptoms may include:

  • an oozing, crusting, or bleeding open sore
  • a reddish or discolored patch that itches but does not hurt
  • a waxy, ill-defined area that resembles a scar
  • a growth that looks like a wart
  • a raised growth that has a dip in the center
  • painless, shiny, firm bumps that might be red, blue, or pink

Skin cancer that spreads along the nerves might cause pain, itching, numbness, or a crawling sensation under the skin. People might also notice neck, armpit, or groin bumps if the cancer has spread to the lymph nodes.

The leading cause of all skin cancers, including melanoma, is UV light exposure from the sun and tanning beds.

UV light can damage the skin’s DNA. While the skin can repair itself, excessive UV light exposure can cause more skin damage than the body can fix, leading to skin cell changes and mutations that can lead to cancer.

Risk factors

A person may have a higher risk of developing melanoma if they:

  • spend long hours outside without skin protection
  • regularly use tanning beds
  • have previously had a severe sunburn
  • have light skin that burns easily
  • have blue or green eyes and blonde or red hair
  • are 50 years or older
  • have more than 50 moles, one very large mole, or a mole that appears irregular
  • have a compromised immune system
  • have blood relatives with a history of melanoma and other skin cancers
  • have a personal history of skin cancer, breast cancer, or thyroid cancer
  • people with a rare condition known as xeroderma pigmentosum, which prevents UV damage repair

People with a higher risk of melanomas may benefit from monthly skin self-checks. They can report unusual skin changes to a healthcare professional, such as a dermatologist.

A doctor will first visually examine the skin and ask about factors such as sun exposure and family history. They might use a visual device called a dermoscope to look closely at the skin.

They will likely request a biopsy if they suspect a lesion is atypical. A biopsy can help identify whether a person has skin cancer, how advanced it is, and what type it is.

If a doctor suspects melanoma, diagnosis may also involve CT scans of other organs, such as the brain, to verify whether the cancer has spread to other parts of the body.

A first-line treatment for skin cancer is to remove the cancerous growth surgically.

However, because melanoma is more aggressive than other types of skin cancer, additional treatment options may be necessary to prevent and manage the spread of the disease.

Treatment depends on several factors, including:

  • the type of cancer
  • the size of the cancer
  • how far it has spread
  • the overall health of the person

Nonmelanoma skin cancer treatment

Treatments to remove NMSC may include:

  • excision, which involves removing the cancerous tissue and some surrounding healthy tissue
  • curettage and desiccation, which involves the use of a smaller, spoon-like device to remove smaller cancers
  • cryotherapy, which involves freezing off smaller cancers using liquid nitrogen
  • Mohs surgery, a technique that involves removing the cancer in layers to preserve healthy tissue

NMSC treatment may also involve radiation therapy or chemotherapy creams to reduce the risk of the cancer returning after treatment.

Melanoma treatment

Surgeons use similar procedures to remove melanomas.

However, because melanoma is an aggressive form of skin cancer, doctors may also recommend the following to prevent recurrence:

Learn more about skin cancer treatments.

Preventing all types of skin cancer involves protecting the skin from UV rays.

The AAD recommends the following prevention measures:

  • Seek shade during peak sun hours between 10 a.m. and 2 p.m.
  • Wear clothing that provides adequate skin cover.
  • Use a broad-spectrum sunscreen with an SPF of 30 or higher, even on cloudy days.
  • Reapply sunscreen every 2 hours.
  • Avoid using tanning beds.

Additionally, regular skin self-checks can help identify suspicious moles and skin changes early.

Skin cancer refers to any cancer that develops in a skin cell. Melanoma is a rare but aggressive type of skin cancer.

Excessive exposure to UV rays is the leading cause of all skin cancers, including melanoma.

Treatment for skin cancer depends on its type and severity and may include surgical removal, chemotherapy, radiation, and topical therapies.