Patient Education

Types of Skin Cancer: Basal Cell, Squamous Cell, and Melanoma

Understand the differences between the three most common skin cancers, what to watch for at home, and why early evaluation matters.

Three common types, very different behaviors

Skin cancer is the most common cancer in the United States. The three most frequent types are basal cell carcinoma, squamous cell carcinoma, and melanoma. They look different, behave differently, and are treated differently, but they share one thing in common: early detection gives the best outcomes.

This guide is general patient education. It is not a diagnosis. If you have a spot that is new, changing, or does not feel right, please have it evaluated in person by a dermatologist.

Overview

Basal Cell Carcinoma (BCC)

The most common form of skin cancer in the United States and a frequent diagnosis in sun-exposed Alaskans.

What it is

Basal cell carcinoma starts in the basal cells of the outermost layer of skin. It tends to grow slowly and rarely spreads to other parts of the body, but it can grow into surrounding skin and underlying tissue if left untreated.

Where it tends to appear

Most often on the face, ears, scalp, neck, shoulders, and back, where skin has had the most sun exposure over time.

What it may look like

A pearly or waxy bump, sometimes with visible small blood vessels
A flat, flesh-colored or brown scar-like patch
A sore that bleeds, scabs, heals, and then returns
A small, shiny pink growth with a slightly rolled edge

Why early evaluation matters

BCC is highly treatable when caught early. Treatment is typically straightforward, with excellent outcomes. Larger or recurrent BCCs may need more involved care.

Overview

Squamous Cell Carcinoma (SCC)

The second most common skin cancer, with a higher chance of spreading than basal cell carcinoma if not treated.

What it is

Squamous cell carcinoma develops in the flat squamous cells of the skin's surface. It can arise from a pre-cancerous spot called an actinic keratosis. Compared with BCC, SCC has a greater potential to grow deeper and, in some cases, spread to lymph nodes or other tissues.

Where it tends to appear

Commonly on the face, ears, lips, scalp, neck, backs of hands, and forearms. Patients who are immunosuppressed or have had many sunburns are at higher risk.

What it may look like

A firm red bump or nodule
A scaly, crusted patch that may bleed
A sore that does not heal, or heals and returns
A rough, sandpaper-like spot on chronically sun-exposed skin

Why early evaluation matters

Most SCCs are curable when found early. Earlier treatment usually means simpler treatment, smaller scars, and a lower chance of the cancer spreading.

Overview

Melanoma

Less common than BCC or SCC, but the most serious of the three because it can spread to other organs if not treated early.

What it is

Melanoma develops in the pigment-producing cells of the skin called melanocytes. It can begin in an existing mole or appear as a new spot. Early-stage melanoma is highly treatable, which is why early detection is so important.

Where it tends to appear

Anywhere on the body, including areas with little sun exposure, the scalp, soles of the feet, under nails, or on the palms. In women, melanoma is often found on the legs; in men, on the trunk.

What it may look like

Asymmetry: one half of the spot does not match the other
Border irregularity: scalloped, notched, or poorly defined edges
Color variation: shades of brown, black, red, white, or blue within one spot
Diameter larger than a pencil eraser (about 6 mm), though melanomas can be smaller
Evolving: any spot that changes in size, shape, color, or feel over time

Why early evaluation matters

When melanoma is found before it has spread, outcomes are typically excellent. Any new or changing mole, or a mole that looks different from your others, should be evaluated promptly.

Warning signs to watch for

Get familiar with your skin and check it about once a month. Use a hand mirror for hard-to-see areas, or ask a partner to help with your back and scalp. Have a dermatologist look at any spot that fits the following:

A new mole or growth, especially in adulthood
A spot that changes in size, shape, color, or texture
A sore that bleeds, scabs, or does not heal within a few weeks
A pearly, waxy bump or a flat scar-like patch
A scaly red patch that is tender, itchy, or crusty
A mole that looks different from your other moles (the ABCDEs)
Any spot that just does not feel right to you

When in doubt, get it checked. Most spots are not skin cancer, but a quick exam can give you peace of mind, and early action is what makes skin cancer so treatable.

When to schedule a skin exam

A professional skin exam takes only a few minutes and is one of the most effective ways to find skin cancer early. Consider scheduling if any of the following applies to you.

You have never had a skin exam

A baseline full-body skin exam gives your dermatologist a starting point so future changes are easier to spot.

You notice something new or changing

Do not wait for an annual visit if you see a new spot, a changing mole, or a sore that does not heal.

You are higher risk

Personal or family history of skin cancer, fair skin, many moles, prior sunburns, immunosuppression, or significant outdoor exposure all increase risk.

It has been a year or more

Most adults benefit from a yearly skin cancer screening. Higher-risk patients may be advised to come in more often.

Skin Cancer Screening

What to expect from a yearly screening and when to come in for an exam.

Learn more

Mohs Surgery

The surgical gold standard for many basal and squamous cell skin cancers, with same-day clearance.

Learn about Mohs

GentleCure

A non-surgical option that may help treat select basal and squamous cell skin cancers.

Explore GentleCure

Frequently asked questions

What is the most common type of skin cancer?

Basal cell carcinoma (BCC) is by far the most common form of skin cancer. It grows slowly and is highly treatable when caught early, but it can damage surrounding tissue if left untreated.

How is skin cancer diagnosed?

A dermatologist examines the skin, often using a dermatoscope, and may perform a small skin biopsy of any concerning spot. A pathologist then examines the tissue under a microscope to confirm whether skin cancer is present and, if so, what type.

How do I tell a normal mole from a melanoma?

A useful guide is the ABCDEs: Asymmetry, Border irregularity, Color variation, Diameter larger than a pencil eraser, and Evolving over time. A mole that looks different from your other moles, or any spot that is changing, should be evaluated by a dermatologist. This is general guidance and is not a substitute for an in-person exam.

Are BCC and SCC dangerous?

Most basal and squamous cell skin cancers are highly treatable when found early. SCC has a greater chance of spreading than BCC if left untreated, which is one reason early evaluation and treatment matters.

Can people with darker skin tones get skin cancer?

Yes. Although less common, skin cancer occurs in people of all skin tones. In darker skin tones, melanoma is more often found in areas with less sun exposure, such as the palms, soles, under the nails, or inside the mouth. Any new or changing spot should be evaluated.

How often should I get a skin cancer screening?

Most adults benefit from a yearly full-body skin exam. Patients with a personal history of skin cancer, many atypical moles, immunosuppression, or significant sun exposure may be advised to come in more frequently.

Medical disclaimer

The information on this page is provided for general educational purposes only and is not medical advice. It is not a substitute for an in-person evaluation, diagnosis, or treatment by a qualified healthcare professional. Reading this page does not establish a patient-provider relationship. If you have a spot that concerns you, please schedule an appointment with a dermatologist. If you believe you are experiencing a medical emergency, call 911.

Have a spot you would like checked?

Our team at Advanced Dermatology of Alaska can evaluate any new or changing spot and recommend next steps. Same-week appointments are often available in Wasilla and Anchorage.