Skin Cancer

BCC vs SCC vs Melanoma – How Each Type Looks, Grows, and When to Worry

Understanding the three main types of skin cancer, their warning signs, and when to seek medical attention.

January 27, 2025Evidence-based

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Skin cancer is the most common form of cancer, but not all skin cancers are the same. The three main types—basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma—have different appearances, growth rates, and risks. Understanding these differences can help you recognize warning signs early and seek appropriate care.

The Three Main Types of Skin Cancer

While there are other rare types of skin cancer, these three account for the vast majority of cases. Each has distinct characteristics that can help identify them.

Basal Cell Carcinoma (BCC)

Most common

Growth: Slow (months to years)

Squamous Cell Carcinoma (SCC)

Second most common

Growth: Moderate (weeks to months)

Melanoma

Less common but most dangerous

Growth: Fast (weeks to months)

Basal Cell Carcinoma (BCC)

Basal cell carcinoma is the most common type of skin cancer, accounting for about 80% of all skin cancers. It develops in the basal cells at the bottom of the epidermis (outer skin layer) and is strongly linked to cumulative sun exposure.

What BCC Typically Looks Like:

Pearly or waxy bump: Flesh-colored or pinkish, often with visible blood vessels
Flat, scar-like lesion: White or yellowish area that looks like a scar without history of injury
Non-healing sore: A sore that bleeds, crusts over, then reopens repeatedly
Pink growth with raised edges: May have a dip in the center, like a crater

Good news: BCC very rarely spreads to other parts of the body. However, if left untreated, it can grow and invade nearby tissue, causing significant local damage. Treatment is straightforward and highly effective when caught early.

Squamous Cell Carcinoma (SCC)

Squamous cell carcinoma is the second most common type of skin cancer. It develops in the squamous cells that make up the middle and outer layers of the skin. SCC is more likely than BCC to spread if left untreated.

What SCC Typically Looks Like:

Rough, scaly red patch: May crust or bleed, often on sun-exposed areas
Thickened, wart-like growth: Raised bump with a rough, crusty surface
Open sore or ulcer: A sore that doesn't heal, or heals and returns
Crusted lip lesion: Persistent rough patch on the lip, common site for SCC

Melanoma

Melanoma is the most dangerous type of skin cancer. It develops in the melanocytes—the cells that give skin its color. While less common than BCC or SCC, melanoma is responsible for most skin cancer deaths because of its ability to spread quickly.

The ABCDE Rule for Melanoma:

Asymmetry (A): One half doesn't match the other half
Border (B): Irregular, ragged, notched, or blurred edges
Color (C): Multiple colors: brown, black, red, white, blue
Diameter (D): Usually larger than 6mm, but can be smaller
Evolution (E): Any change in size, shape, color, or symptoms

Learn more about the ABCDE rule in our detailed guide: The ABCDE Rule for Melanoma

When to Seek Urgent Medical Attention

  • A mole or spot that's changing over weeks to months
  • Bleeding or crusting without any injury
  • A sore that won't heal or keeps coming back
  • Rapidly growing bump or lesion
  • New dark spot in adulthood that's evolving
  • An 'ugly duckling' spot that looks different from your other moles
  • Painful or ulcerated lesion
  • Any suspicious spot in a person with history of skin cancer

Frequently Asked Questions

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Medical Disclaimer: This article is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified healthcare provider with any questions about a skin condition. If you think you may have a medical emergency, call your doctor or emergency services immediately.

Sources

  1. Skin Cancer: OverviewAmerican Academy of Dermatology (2024)
  2. Melanoma OverviewSkin Cancer Foundation (2024)
  3. Basal Cell Carcinoma OverviewSkin Cancer Foundation (2024)
  4. Squamous Cell Carcinoma OverviewSkin Cancer Foundation (2024)
  5. Skin Cancer (Non-Melanoma)NHS UK (2024)

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