SkincareSafety Guide

Skin

Understand your skin type, tone, and what your skin is doing.

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Start here

Skin typesThe main skin types and how they differ.Find your skin typeA practical identification guide.What different skin types look likeVisual differences between common skin types.

Common skin questions

Oily skinWhat oily skin means and how to read it.Skin type changesHow skin type can shift over time.Skin type and ageHow visible aging differs by skin type.
Not sure where to start?Use the skin-type guide before choosing routines or ingredients.

Concerns

Start from a skin problem or visible change.

View concern guides

Oil and acne

Why oily skin happensThe main drivers behind excess oil.Oily skin and acneHow oil can contribute to breakouts.Can oily skin cause acne?A direct answer to the oil-acne link.

Changes and warning signs

Stress and oily skinHow stress may affect oiliness.Dehydration and oilinessWhy skin can feel oily and dehydrated.Skin cancer signsVisual signs that need professional attention.
Looking for a solution?Start with what oily skin actually needs before adding stronger products.

Ingredients

Understand what ingredients do and whether they fit your skin.

View ingredient questions

Explore ingredients

NiacinamideA practical ingredient overview.Vitamin C serumWho can use vitamin C and when to be careful.RetinolHow retinol fits different skin types.

Use safely

Salicylic acidWhere this acne-focused ingredient fits.Niacinamide for all skin typesSuitability across skin types.Ingredient comparisonsUse comparisons to avoid mismatched decisions.
Can my skin use this?Browse compatibility questions before adding a new active.

Routines

Turn skin information into daily decisions.

View routine questions

Daily basics

Does every skin type need moisturizer?A basic routine decision.Does every skin type need sunscreen?Where SPF fits in daily care.What oily skin needsA simple care direction for oily skin.

Adjust over time

Skin changes with ageWhen your routine may need to change.Seasonal skin changesHow weather affects skin behavior.Korean skincare approachWhat is useful beneath the trend.
Starting from scratch?Begin with moisturizer, sunscreen, and one skin-specific need.

Products

A small selection of skincare products recommended by OuterDerm for simple, effective everyday routines.

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Recommended picks

Daily SunscreenDaily UV protection that has to be wearable enough to stick with.Azelaic AcidA focused 10% azelaic acid when uneven tone or blemish marks are the concern.Gentle CleanserComfortable cleansing when tight or squeaky skin is a warning sign.
Not sure where to start?Browse three carefully selected essentials, then ask on WhatsApp before you order.

Learn

Go deeper into skin science, myths, evidence, and safety.

View learning guides

Hazardous ingredients

Safety hubStart with mercury, steroids, PPD and other hazardous substances.Ingredient safety indexBrowse Phase 1 and Phase 2 hazardous ingredients.Mercury in whitening creamsLabel names, Punjab alerts, and what to do now.

Product literacy

Product literacy hubHow to read labels, claims, and INCI lists before you buy.How to read an ingredient labelINCI order, Parfum, and missing-list red flags.Fragrance-free vs unscentedHow to verify a fragrance-free claim on the ingredient list.How to choose sunscreenBroad spectrum, wearability, and a readable pack — not a fairness claim.

Skin science

Skin color geneticsHow inherited traits shape skin color.Skin color typesHow skin tone is commonly grouped.Are skin types genetic?What genetics can and cannot explain.

Evidence and myths

Can all skin types tan?Tanning, risk, and skin type.Is oily skin good or bad?A balanced view of oily skin.Why Korean skin looks flawlessTrend claims translated into practical basics.
Want the evidence layer?Use why-guides when you want causes, mechanisms, and context.

Skin Health & Medical Conditions

What Do Types of Skin Cancer Look Like?

Skin cancer is one of the most common cancers in the world - and also one of the most visible. Knowing what to look for can make a life-saving difference.

Quick answerThe three most common types of skin cancer look different: Melanoma often appears as an asymmetric mole with irregular borders and changing color.

Medically reviewed by Dermatology reviewer · Updated Jul 18, 2026 · 6 min read

Diagram showing ABCDE melanoma warning signs on skin
Most Common TypeBasal cell carcinoma (BCC)
Most DangerousMelanoma
Key WarningABCDE rule for moles
Common LocationSun-exposed areas
Action NeededSee a doctor immediately

Key answer

Medical consultation is essential

If you notice any concerning changes in your skin, see a dermatologist immediately.

Evidence
Strong - Medical consultation is essential
Best for
Understanding what skin cancer looks like
Limitation
Self-diagnosis - always consult a professional

See what the evidence shows

Short version

Story in brief

Skin cancer develops when skin cells grow abnormally, often triggered by UV damage. The three main types are basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma. Each originates from a different type of skin cell and each looks different when it appears.

BCC is the most common type, typically appearing on sun-exposed areas like the face and neck. It often looks like a pearly or waxy bump, a flat, flesh-colored lesion, or a sore that doesn't heal. SCC often appears as a firm, red bump with a rough, scaly surface or as a flat lesion with a scaly crust.

Melanoma is the most dangerous and can appear in many forms - often as a new spot or an existing mole that changes in size, shape, or color. It can be black, brown, or even red or white. Early detection dramatically improves outcomes, which is why regular skin checks are so important.

Mental model

Visual explanation

Evidence

What the evidence shows

Evidence-based risk factors and screening recommendations.

  • UV exposure → skin cancer

    Well-established link

  • ABCDE rule utility

    Validated screening tool

  • Early detection benefits

    Dramatically improves outcomes

Use this section to decide

Does this advice apply to me?

Find the concern or goal closest to yours, then use the fit signal to decide how much weight to give this guide.
Strong fit means the advice is central to that goal.Depends means formula, tolerance, or context matters more.Use caution means do not treat it as the main answer.

  • If your goal is

    BCCDepends
    Fit signal
    Possible fit

    Pearly, waxy bump with visible blood vessels

  • If your goal is

    SCCDepends
    Fit signal
    Possible fit

    Firm, red bump with scaly surface

  • If your goal is

    MelanomaUse caution
    Fit signal
    Limited evidence

    Asymmetric, irregular borders, multiple colors

Practical use

How to use it

  1. Perform regular skin checks

    Examine your skin monthly, using mirrors to check hard-to-see areas.

  2. Apply the ABCDE rule

    Look for asymmetry, irregular borders, multiple colors, large diameter, or changes.

  3. See a dermatologist for any concerns

    Don't wait - early detection saves lives.

Safety

Side effects and cautions

  • Assuming a spot is harmless because it doesn't look "scary"

    Skin cancer can appear in many forms - any new or changing spot should be evaluated.

  • Delaying a doctor visit due to fear

    Early detection dramatically improves outcomes.

  • Relying solely on photos from the internet for self-diagnosis

    Professional medical evaluation is essential for accurate diagnosis.

  • New or changing mole

    Common · Evaluate with ABCDE rule; see a doctor if concerned

  • Sore that doesn't heal

    Common in BCC and SCC · See a doctor immediately

  • Scaly or bleeding bump

    Common in SCC · Medical evaluation needed

Fit

Who should be careful

  • Self-diagnosis - always consult a professional

Worth noting

Small details that can change the answer

  • ABCDE Rule. The ABCDE rule is the standard screening tool: Asymmetry, Border, Color, Diameter, Evolution.
  • BCC Appearance. Basal cell carcinoma often looks like a shiny, pearly bump with visible blood vessels.
  • SCC Appearance. Squamous cell carcinoma appears as a firm, red bump with a rough, scaly surface.
  • Melanoma. Melanoma can appear in colors ranging from black to brown to pink or even white.

The three main types of skin cancer look different: BCC is pearly, SCC is scaly, melanoma is often dark and irregular.

The ABCDE rule is a simple screening tool that can help you spot potential melanomas.

Any new, changing, or unusual skin growth should be evaluated by a doctor.

Skin cancer is highly treatable when detected early.

Regular self-examinations and dermatological checks are essential for prevention.

Definition

Basal cell carcinoma (BCC)

BCC is the most common type of skin cancer. It typically appears on sun-exposed skin, especially the face, ears, neck, and hands. It may look like: a pearly or waxy bump (often with visible blood vessels), a flat, flesh-colored or brown scar-like lesion, or a sore that bleeds or doesn't heal.

Definition

Squamous cell carcinoma (SCC)

SCC is the second most common type. It appears on sun-exposed skin and can also develop in scars or ulcers. It often looks like: a firm, red nodule with a rough, scaly surface, a flat lesion with a scaly crust, or a sore that doesn't heal.

Definition

Melanoma

Melanoma is the most dangerous form of skin cancer. It can develop anywhere on the body, including skin not typically exposed to the sun. The ABCDE rule helps identify potential melanomas: Asymmetry, irregular Border, multiple Colors, Diameter greater than 6mm, Evolving (changing in size, shape, or color).

Risks

When to see a doctor immediately

Any skin growth that is new, changing, or unusual should be evaluated by a medical professional. Pay particular attention to:

  • Moles that are asymmetric or have irregular borders
  • Lesions with multiple colors or uneven pigmentation
  • Spots that are growing or changing over time
  • Sores that don't heal or keep returning
  • Bumps that are painful, itchy, or bleeding

Clinical Guidance

Medical guidance

  • Perform regular skin self-examinations, checking all areas of the body.
  • Use the ABCDE rule as a screening tool, not a diagnostic tool.
  • Schedule routine dermatological skin checks, especially if you have risk factors.
  • Take photos of moles or spots to track changes over time.
  • See a dermatologist immediately if you notice any concerning changes.

Questions

Frequently asked questions

Is all skin cancer dark or black?

No - BCC and SCC are often flesh-colored, pink, or red. Melanoma can be dark but can also be pink or skin-colored.

Can skin cancer appear on skin that's not sun-exposed?

Yes - melanoma, in particular, can appear anywhere on the body.

Does the ABCDE rule apply to all skin cancers?

It's primarily for melanoma, but BCC and SCC also have distinct visual signs.

What if I have many moles?

Having many moles is a risk factor - you should have regular dermatological checks.