Skin Cancer • Cancer – uncontrolled cell growth • Caused by damage to the DNA (in the nucleus) usually through chemicals or radiation

Skin Cancer Skin cancer is the most common type of cancer 2 out of 5 cancers are skin cancers

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Tumor Types

Prevention • Ultraviolet Radiation is the main cause of all skin cancers

• Two types of tumors • Benign • Does not spread (encapsulated) • Malignant: these are the cancerous ones • Metastasized (moves) to other parts of the body

Skin Cancer Types

Basal Cell Carcinoma

• 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 Slide 4.30

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Skin Cancer Types

Basal Cell Carcinoma

• 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

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Squamous Cell Carcinoma

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Cumulative Effects • IMPORTANT TO KNOW • Basal cell & squamous cell carcinomas are due to cumulative effects of the sun’s radiation (or chemical exposures as well) • These tend to develop in ages 30-40s after years of daily sun exposure

Skin Cancer Types

Intensive Effects

• Malignant melanoma • Least common BUT most deadly of skin cancers • Originates melanocytes • Metastasizes rapidly to lymph and blood vessels • Early detection is critical – see notes for survival rates Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

• Malignant Melanoma tends to occur in younger ages (as well as older people) • It is due to brief intense exposures (aka: sunburns) • This is the most serious form of skin cancer and MUST be caught early to be treated successfully!

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ABCD Rule

Malignant Melanoma

• 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 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

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Melanomas

Melanomas

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

Burns

• 2 main dangers • Dehydration–Loss of fluids & Electrolytes lead to:

•Renal Shutdown •Circulatory shock

• Infection •Skin (mechanical)barrier lost •Immune system depresses

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

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Partial Thickness Burns

Rule of nines diagram

• First-degree burns

• Used to estimate the % extent of skin burned so doctors will know how much fluid to replace for rehydration to prevent

• Only epidermis is damaged • Local redness, swelling, & pain • Usually heal in 2-3 days (short time period) with NO scarring

– Circulatory shock – Renal failure

• Need to memorize & be able to use

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

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Partial Thickness Burns • 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

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

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Full Thickness Burns • Third-degree burns • Epidermis, Dermis and all structures within are completely destroyed • Usually painless at site of burn due to destruction of sense recept • Burn is gray-white, tan, brown, black, or deep cherry red • Surrounded by areas of 1st & 2nd degree burns that will be painful • Treatments are numerous but will involve skin grafting of some sort, fluid replacement and debridement – may take months/years Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

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All degrees of burns

• 'Burns surgery for Sum Maya' hi-res | International Nepal Fellowship

Other Integumentary System disorders May help with WS

Boils •Inflammation of hair follicles & sebaceous glands •Common on dorsal neck

Cold Sores Athlete’s Foot •Itchy, red, peeling condition between toes, resulting from fungal infection

•small fluid-filled blisters that itch & sting •Caused by herpes simplex virus

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Skin Homeostatic Imbalances • Infections and allergies • Contact dermatitis • Exposures (ie. Poison ivy)cause allergic reaction

Psoriasis

• Itching, redness & swelling of skin, progressing to blistering Impetigo Caused by bacterial infection Pink, water-filled, raised lesions develop a yellow crust & rupture • usually around mouth/nose • Highly contagious Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

•Cause is unknown •Triggered by trauma, infection, stress •Reddened epidermal lesions covered w/dry, silvery scales

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