What is the most dangerous skin cancer

This information provided by Cancer Council Western Australia (external site).

There are 3 types of skin cancer and they are named after the type of skin cell they start from. These are basal cell carcinoma, squamous cell carcinoma and melanoma skin cancer.

Basal cell carcinoma

Most common form of skin cancer but the least dangerous.
Appear as round or flattened lump or scaly spots.
Red, pale or pearly in colour.
May become ulcerated, bleed and fail to heal.
Grows slowly over months or years.
Usually found on the upper body, head or neck.
Also known as non-melanoma skin cancer.

Squamous cell carcinoma

Less common, but more dangerous than basal cell carcinoma.
1 to 2 per cent can spread and cause death.
Look for scaly red areas that may bleed easily, ulcers or non-healing sores that are often painful.
Grows over a period of months.
Often found on lips, ears and scalp.
Also known as non-melanoma skin cancer.

Melanoma skin cancer

Least common but most serious form of skin cancer.
Can appear in a new or an existing spot, freckle or mole that changes colour, size or shape.
Grows over weeks to months anywhere on the body (not just areas that get lots of sun).
If untreated, cancer cells can spread to other parts of the body.
Occurs most frequently on the upper back in males and on the lower leg in females.

The warning signs of UV damage to the skin and eyes

The following conditions are not cancer but may predispose you to skin cancer or be a warning sign that damage to the skin or eyes has occurred.

Dysplastic naevi

Are odd shaped (also called atypical) moles that aren't cancer, but may indicate a greater risk of developing melanoma.
Usually 5 to 10mm wide, with uneven colouring.
If you have lots of odd shaped moles you are at a higher risk of developing skin cancer and should have your skin checked regularly by your doctor.

Solar kertoses

Generally hard, red, scaly spots on sun exposed areas of the skin.
Occur commonly on the head, neck and the backs of the hands.
Are a warning sign that the skin has been damaged by the sun and that skin cancers may develop.

Eye damage

Sun exposure can cause burns to the eye similar to sunburn of the skin which may lead to:
- cataracts (clouding of the lens)
- pterygium (tissue covering the cornea)
- cancer of the conjunctiva or cornea.

Remember

Skin cancer develops when a cell in the skin goes through a series of changes.
Exposure to ultraviolet (UV) radiation is the main factor that causes skin cells to become cancer cells.
Ultraviolet (UV) radiation can damage skin cells and stop the immune system from working properly.

This information provided by

Acknowledgements
Cancer Council Western Australia

This publication is provided for education and information purposes only. It is not a substitute for professional medical care. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your healthcare professional. Readers should note that over time currency and completeness of the information may change. All users should seek advice from a qualified healthcare professional for a diagnosis and answers to their medical questions.

How Common Is Skin Cancer?

It is estimated that one in five Americans will get skin cancer at some point in their life.

Basal Cell Carcinoma

Basal cell carcinoma (BCC) is the most frequently occurring of all cancers and is the most common skin cancer. More than 4 million cases are diagnosed every year in the United States.

Basal cells are one of the three types of cells found in the top layer of the skin. BCC typically occurs due to damage from sun exposure or from ultraviolet (UV) radiation exposure from indoor tanning. This triggers abnormal and uncontrollable growth of the basal cells.

Although BCC is relatively slow-growing and doesn’t usually spread to surrounding areas, it can metastasize if left untreated.

How Often Does BCC Spread?

Metastasis is rare with BCC, occurring in between 0.0028 and 0.55% of all cases. When it does occur, the lymph nodes, lungs, and bone are the most common sites of metastasis.

If BCC remains localized, there is a five-year survival rate of 100%. If BCC metastasizes, the outcomes are generally poor with median survival times ranging from eight months to 3.5 years.

Squamous Cell Carcinoma

Squamous cell carcinoma (SCC) is the second most common form of skin cancer. Squamous cells are found near the surface of the skin. SCC occurs when damage to DNA occurs through exposure to UV radiation and triggers abnormal, fast growth of squamous cells. This can occur due to heavy exposure to the sun.

SCCs can present as:

Open sores
Rough skin
Thickened or wart-like skin
Scaly red patches of skin

Affected skin most commonly occurs in areas of the body that have been exposed to the sun.

Although SCC is relatively slow-growing, it is slightly more likely to metastasize than BCC.

How Often Does SCC Spread?

Studies suggest that around 1.4% of people with SCC will experience metastasis.

As with BCC, the five-year survival rate is high—hovering around 99%—in the absence of metastasis. With metastasis, the three-year survival is roughly 29% in women and 46% in men.

Melanoma

Melanoma is a cancer that begins in skin cells called melanocytes, which give skin color. Melanoma may take the appearance of a mole, even in parts of the skin not exposed to the sun.

Melanoma is a serious form of cancer and is characterized by its aggressiveness.

One way of identifying melanoma is through the "ugly duckling" sign. This technique for identifying warning signs of melanoma works on the basis that most "normal" moles on the body are similar to one another in appearance, but melanomas by comparison will stand out like an ugly duckling. Compared to surrounding moles, ugly duckling lesions could be lighter, darker, smaller, or larger compared to others.

Melanoma is less common than SCC and BCC, but it is more dangerous because it can spread rapidly to other organs if not treated early.

Risk factors for melanoma include:

Excessive or unprotected UV exposure: This can be either from the sun or indoor tanning beds.
Multiple moles: Having large moles that are bigger than the eraser on a pencil, or having multiple moles on the body increases the risk of melanoma.
Weakened immune system: This makes you more susceptible to melanoma.
Fair skin: Melanoma is more common in those with light eyes, light or red hair, and people with fair skin.
A history of skin cancer: Your likelihood of melanoma increases if you have a history of skin cancer.
Genetics: One in 10 patients with melanoma has a family member who has also had melanoma.

When treated in the earliest stages, nearly 99% of people with melanoma will experience remission. That figure quickly drops when there is regional and distant spread.

Five-Year Relative Survival
Stage	Percentage of Cases by Stage	5-Year Relative Survival
Localized	83%	99.0%
Regional	9%	66.2%
Distant	4%	27.3%

Merkel Cell Carcinoma

Merkel cell carcinoma (MCC) is a rare and aggressive form of skin cancer. About 2,000 cases of MCC are diagnosed in the United States each year.

MCC tumors can appear on areas of the skin exposed to the sun, but not in all instances. They can appear as pimple-like lumps and can be skin-colored, purple, red, or bluish red. Their rapid growth is often what draws attention to them.

Risk factors for MCC include:

A history of unprotected UV exposure, either from the sun or indoor tanning
Weakened immune system
Skin cancer history
Being over 50 years old
Having fair skin (although MCC can affect anyone)
Being male (men are more likely than women to get MCC)

How Often Does MCC Spread?

Around one-third to one-half of people with MCC will experience metastasis, most commonly to the brain, lungs, liver, or bones.

Treatment options for MCC vary based on the stage of the disease and how healthy a patient is overall. Treatment options include:

Surgical removal of the tumor
Radiation
Immunotherapy
Chemotherapy

A Word From Verywell

A diagnosis of skin cancer can be overwhelming. Survival statistics are based on everyone who has a disease—regardless of their age, overall health, or other factors that might positively or negatively influence survival. Early diagnosis and preventative measures like practicing sun safety can improve outcomes and odds of survival.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Centers for Disease Control and Prevention. Melanoma of the skin statistics.
American Cancer Society. Survival rates for melanoma skin cancer.
Guy GP, Thomas CC, Thompson T, et al. Vital signs: melanoma incidence and mortality trends and projections - United States. MMWR Morb Mortal Wkly Rep ;64(21):591-596.
Skin Cancer Foundation. Basel cell carcinoma overview.
Mehta KS, Mahajan VK, Chauhan PS, et al. Metastatic basal cell carcinoma: a biological continuum of basal cell carcinoma? Case Reports in Dermatological Medicine. 2012;2012:1-4. doi:10.1155/2012/157187
Skin Cancer Foundation. Squamous cell carcinoma.
Skin Cancer Foundation. How Serious Is a Squamous Cell Carcinoma?
Ames FC, Hickey RC. Metastasis from squamous cell skin cancer of the extremities: Southern Medical Journal. 1982;75(8):920-923. doi:10.1097/00007611-198208000-00005
American Cancer Society. What is melanoma skin cancer?
American Cancer Society. Risk factors for melanoma skin cancer.
National Cancer Institute. Cancer Stat Facts: Melanoma of the Skin
American Cancer Society. Key statistics for merkel cell carcinoma.
Paulson KG, Park SY, Vandeven NA, et al. Merkel cell carcinoma: Current US incidence and projected increases based on changing demographics. J Am Acad Dermatol. 2018;78(3):457-463.e2. doi:10.1016/j.jaad.2017.10.028

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What are the three most dangerous skin cancers?

Skin cancer — the abnormal growth of skin cells — most often develops on skin exposed to the sun. But this common form of cancer can also occur on areas of your skin not ordinarily exposed to sunlight. There are three major types of skin cancer — basal cell carcinoma, squamous cell carcinoma and melanoma.

Which skin cancer is the least dangerous?

Basal cell carcinoma Most common form of skin cancer but the least dangerous. Appear as round or flattened lump or scaly spots.

What are the 4 types of skin cancer?

There are 4 main types of skin cancer:.

Basal cell carcinoma. Basal cells are the round cells found in the lower epidermis. ... .

Squamous cell carcinoma. Most of the epidermis is made up of flat, scale-like cells called squamous cells. ... .

Merkel cell cancer. ... .

Melanoma..

Which is more serious basal cell or squamous cell carcinoma?

Though not as common as basal cell (about one million new cases a year), squamous cell is more serious because it is likely to spread (metastasize). Treated early, the cure rate is over 90%, but metastases occur in 1%–5% of cases.