Skin Cancer

Skin cancer is the most common type of cancer

2 out of 5 cancers are skin cancers

Skin Cancer

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• Cancer – uncontrolled cell growth • Caused by damage to the DNA (in the

nucleus) usually through chemicals or radiation

Tumor Types •  Two types of tumors

•  Benign

•  Does not spread (encapsulated)

•  Malignant: these are the cancerous ones

•  Metastasized (moves) to other parts of the body

Prevention n  Ultraviolet Radiation is the main cause of all

skin cancers

Skin Cancer Types

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• Basal cell carcinoma • Least malignant - Most common type • Arises from stratum basale • cannot produce keratin • Boundary lost between dermis and

epidermis

Skin Cancer Types

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• Basal cell carcinoma • Least malignant - Most common type • Arises from stratum basale • cannot produce keratin • Boundary lost between dermis and

epidermis •  90% of skin cancers are basal cell •  Seldom metastasizes – treated surgically or

by radiation – 99% cure rate if caught early

Basal Cell Carcinoma

Basal Cell Carcinoma

Skin Cancer Types

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• Squamous cell carcinoma • 2nd most common skin cancer – most

common in darker skinned people • Arises from stratum spinosum • Metastasizes to lymph nodes if left

untreated • 1500-2000 deaths in US per year

• Early removal allows a good chance of cure

Squamous Cell Carcinoma

Cumulative Effects

n  IMPORTANT TO KNOW n  Basal cell & squamous cell carcinomas are due

to cumulative effects of the sun’s radiation (or chemical exposures as well)

n  These tend to develop in ages 30-40s after years of daily sun exposure

Skin Cancer Types

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• Malignant melanoma • Least common BUT most deadly of skin

cancers • Originates melanocytes • Metastasizes rapidly to lymph and blood

vessels • Early detection is critical

Intensive Effects

n  Malignant Melanoma occurs in younger as well as older people

n  It is due to brief intense exposures (aka: sunburns)

n  This is the most serious form of skin cancer and MUST be caught early to be treated successfully!

ABCD Rule

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•  A = Asymmetry • Two sides of pigmented mole do not match

•  B = Border irregularity • Borders of mole are not smooth

•  C = Color • Different colors in pigmented area

•  D = Diameter • Spot is larger then 6 mm in diameter (pencil

eraser) • Mole starts growing/changing in size

Malignant Melanoma

Melanomas

Melanomas

Burns

Burns

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•  Define: Protein denaturation and cell death caused by heat, electricity, UV radiation, or chemicals

• 2 main dangers

• Dehydration–Loss of fluids & Electrolytes lead to:

• Renal Shutdown

• Circulatory shock

• Infection • Skin (mechanical)barrier lost

• Immune system depresses

Rule of nines diagram

n  Used to estimate the % extent of skin burned so doctors will know how much fluid to replace for rehydration to prevent n  Circulatory shock n  Renal failure

Epidermal Burns

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•  First-degree burns • Only epidermis is damaged • Local redness, swelling, & pain • Usually heal in 2-3 days (short time period)

with NO scarring

Partial Thickness Burns

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• Second degree burns • Epidermis and upper dermis & structures

within dermis are damaged • Appearance of blisters of any size • Skin regeneration in 3-4 weeks with some

scarring • There is a danger of infection

Full Thickness Burns

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•  Third-degree burns • Epidermis, Dermis and Hypodermis are

destroyed • Usually painless at site of burn due to

destruction of sense recepters • Surrounded by areas of 1st & 2nd degree

burns that will be painful • Treatments are numerous but will involve

skin grafting of some sort and fluid replacement– may take months/years