Anatomy and Physiology / Unit 3: The Integumentary System
3.6 Wound Healing and Skin Cancer
Notes
- Healing of a deep wound: (1) bleeding and a blood clot forms a scab; (2) inflammation and granulation tissue (new capillaries and fibroblasts) form; (3) epithelium regenerates under the scab; (4) fibrosis leaves scar tissue.
- Shallow wounds heal by regeneration of epithelium. Large wounds may form hypertrophic scars.
- Skin cancer is linked to UV exposure. Basal cell carcinoma is the most common and rarely spreads. Squamous cell carcinoma arises from stratum spinosum cells and may spread. Melanoma arises from melanocytes, is the most dangerous, and can spread quickly.
- ABCDE rule for melanoma: Asymmetry, Border irregular, Color varied, Diameter over 6 mm, Evolving (changing).
- Prevention: sunscreen, shade, avoid tanning beds.
Practice
Which skin cancer arises from melanocytes and is the most likely to spread?
Melanoma is a cancer of pigment cells and metastasizes readily.
A mole is asymmetrical, has an irregular border, varied color and is growing. This pattern fits:
These are the A, B, C and E warning signs.
In wound healing, granulation tissue consists mainly of:
Granulation tissue is soft, pink, richly vascular tissue that forms the foundation for repair.
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