Types of Skin Cancer and Their Early Signs: Basal Cell, Squamous Cell and Melanoma

Skin cancer is the most common cancer in the United States: at least 1 in 5 Americans will develop it by age 70. The good news is that it is also the cancer you can see. Most skin cancers grow on the surface, where you or your provider can spot them early, when treatment is simplest and cure rates are highest.

There are three main types, basal cell carcinoma, squamous cell carcinoma and melanoma, plus rarer cancers and a common precancer called actinic keratosis. This guide shows what each looks like, where it tends to appear, how serious it is and how it is treated.

The main types of skin cancer at a glance

Type	Early signs	How serious
Basal cell carcinoma	A pearly or shiny bump, a pink patch, or a sore that bleeds, heals and comes back	Most common; grows slowly and rarely spreads, but can damage nearby tissue
Squamous cell carcinoma	A rough, scaly red patch, a firm dome-shaped bump, or a sore that will not heal	Second most common; can spread if left untreated
Melanoma	A new dark spot or a changing mole, often uneven in shape and color	Less common but the most serious; can spread quickly
Merkel cell carcinoma	A fast-growing, painless red, pink or purple bump, often on the head or neck	Rare but aggressive
Actinic keratosis	A dry, rough, scaly spot that feels like sandpaper on sun-exposed skin	A precancer; some can turn into squamous cell carcinoma

Basal cell carcinoma (BCC)

Basal cell carcinoma is the most common cancer of any kind, with about 3.6 million cases diagnosed in the US each year. It usually appears on sun-exposed areas such as the face, ears, scalp, neck, chest and upper back. It often looks like:

• a round, pearly or shiny bump, sometimes with tiny visible blood vessels
• a pink or red, slightly scaly patch
• a sore that bleeds, scabs, seems to heal and then returns
• a flat, scar-like area that is white, yellow or waxy
• on darker skin, a brown or glossy black bump

BCC grows slowly and almost never spreads to other organs, but if it is left alone it can grow deep and damage skin, cartilage or bone, especially on the nose, ears and eyelids.

Squamous cell carcinoma (SCC)

Squamous cell carcinoma is the second most common skin cancer, with about 1.8 million US cases a year. It typically appears on the head, neck, ears, lips, backs of the hands, arms and shins, and often develops from an actinic keratosis. Watch for:

• a rough, scaly, red patch that may crust or bleed
• a firm, raised, dome-shaped bump, sometimes with a central crater
• a sore that does not heal, or heals and reopens
• a wart-like growth

SCC is usually cured when it is treated early, but some can grow deep or spread to lymph nodes, especially on the lips and ears, in scars, or in people with a weakened immune system.

Melanoma

Melanoma develops from the cells that give skin its color. It can start in an existing mole or appear as a new spot, and it can occur anywhere, including skin that rarely sees the sun, the palms, soles and under the nails. Melanoma is less common than BCC and SCC but causes most skin cancer deaths because it can spread quickly. Caught early, it has a 5-year survival rate above 99%.

Use the ABCDEs: asymmetry, irregular border, uneven color, a diameter larger than about 6 mm, and evolving (changing). Our guide to the early signs of melanoma covers these in detail, including melanomas that break the rules.

Rarer skin cancers

• Merkel cell carcinoma: a fast-growing, firm, painless bump that may be red, pink, blue or violet, usually on sun-exposed skin of older adults. It can spread and come back, so it needs prompt treatment.
• Other rare types: dermatofibrosarcoma protuberans, sebaceous carcinoma and Kaposi sarcoma, among others. Any growing, unusual lump deserves a check.

Actinic keratosis: the precancer to know

Actinic keratoses are dry, rough, scaly spots caused by years of sun, often easier to feel than to see. More than 58 million Americans have them. Most never become cancer, but some turn into squamous cell carcinoma, so they are usually treated, for example by freezing, prescription creams or a peel, and they are a sign that your skin has had a lot of sun.

Who is at higher risk?

• Lots of sun exposure over the years, outdoor work or hobbies, and living in a sunny climate such as Southern California
• A history of sunburns or tanning bed use
• Fair skin, light hair or eyes, and freckles
• Many moles or unusual moles
• A personal or family history of skin cancer
• Older age, and a weakened immune system (for example after an organ transplant)

People with darker skin get skin cancer less often but are more likely to be diagnosed late, often on the palms, soles, nails or genitals, so regular skin checks matter for every skin tone.

How skin cancer is diagnosed and treated

A provider examines your skin and, if a spot looks suspicious, takes a skin biopsy under local numbing; results usually take 7 to 10 days. Treatment depends on the type, size and location:

• Surgical removal (excision): the spot is cut out with a margin of healthy skin and stitched.
• Mohs surgery: layer-by-layer removal checked under a microscope during the procedure, used for skin cancers on the face and other delicate areas, with very high cure rates.
• Scraping and cautery: for some small, low-risk basal and squamous cell cancers.
• Prescription creams, freezing or light-based treatment: for actinic keratoses and some very superficial cancers.
• Radiation or medicines: for some advanced or hard-to-treat cancers, managed by specialists.

Prevention

• Use broad-spectrum SPF 30+ sunscreen daily, and reapply every two hours outdoors; read about sunscreen ingredients.
• Seek shade between 10 a.m. and 2 p.m. and wear a hat, sunglasses and UPF clothing.
• Avoid tanning beds.
• Check your skin monthly and have a professional skin exam if you are at higher risk.

Skin cancer screening in Carlsbad

Our dermatology team offers 20 to 30 minute full-body skin cancer screenings, biopsies and treatment of precancers, and guides you through next steps, including referral for Mohs surgery when it is needed. Medical dermatology visits are $150 – $375. See our skin cancer screening and melanoma diagnosis pages, or book a skin check at our South Carlsbad studio on El Camino Real.