Chapter 6, Lesson 4: Skin Disorders

Flashcards from Chapter 6, Lesson 3 of McGraw Hill Anatomy and Physiology, Ninth Edition, by Kenneth S. Saladin.

Skin cancer

Cancer caused by exposure to the UV rays of the sun, most often on the head, neck, and hands of fair-skinned people and the elderly; one of the most common and easily treated cancers

Types of skin cancer

• Basal cell carcinoma (stratum basale)

• Squamous cell carcinoma (stratum spinosum)

• Malignant melanoma (melanocytes)

Basal cell carcinoma

The most common type of skin cancer in the stratum basale; forms a small shiny bump with central depression and is the least dangerous because it seldom metastasizes

Squamous cell carcinoma

Arises from the keratinocytes of the stratum spinosum on the scalp, ears, lower lip, or back of hand and can form a concave ulcer; early detection and removal can allow recovery but if untreated can spread to lymph nodes and become lethal

Malignant melanoma

Skin cancer that arises from melanocytes and is less than 5% of all skin cancer; can be removed if caught early but is fatal when metastasized—greatest risk is genetics in men, redheads, and severe sunburn victims in childhood

Burns

The leading cause of accidental death from extreme tempreatures, radiation, electricity, or acids; fluid loss, infection, or toxic eschar cause most deaths

Eschar

The burned, dead tissue that forms over a burn

Debridement

The removal of eschar

Burn classification

Made to the depth of tissue involvement; first, second and third degree

First-degree burn

Burns that only involve the epidermis that can cause redness, slight edema, and pain but heal within days

Second-degree burn (partial-thickness burn)

Burns that can involve part of the dermis and may appear red, tan, or white with blisters and pain; these take several months to heal and may leave scars

Third-degree burn (full-thickness burn)

Burns that involve all of the dermis and deeper tissue; they require skin grafts and need fluid replacement, infection control, and nutrition to recover

UV Rays

Rays from the sun that have the potential to cause cancer; sunscreens may provide protection but may provide a false sense of security and damage DNA through their chemicals

Skin graft

Taking skin and putting it on a burn (usually of the third degree)

Autograft

Skin grafts taking tissues from another location on the same person’s body

Split-skin graft

Taking the epidermis and part of the dermis from an undamaged area and grafting it elsewhere; is an autograft

Isograft

Using tissue from an identical twin in a skin graft

Homograft (allograft)

Using tissue from an unrelated person in a skin graft

Heterograft (xenograft)

Using tissue from another species in a skin graft

Other graft options

Using the amnion from afterbirth and artificial skin from silicone and collagen