Skin Cancer Skin Cancer Cancer uncontrolled cell growth Caused by damage to the DNA (in the nucleus) usually through chemicals or radiation Skin cancer is the most common type of cancer 2 out of 5 cancers are skin cancers Slide 4.29 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 Ultraviolet Radiation is the main cause of all skin cancers Skin Cancer Types 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 Slide 4.30 1
Basal Cell Carcinoma Skin Cancer Types Squamous cell carcinoma 2 nd 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 Slide 4.30 Squamous Cell Carcinoma Cumulative Effects IMPORTANT TO KNOW Basal cell & squamous cell carcinomas are due to cumulative effectsof 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 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 Intensive Effects 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! Slide 4.31 2
ABCD Rule 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 Slide 4.32 Malignant Melanoma Melanomas Melanomas Burns Burns Define: Protein denaturation and cell death caused by heat, electricity, UV radiation, or chemicals 2 main dangers Dehydration Loss of fluids & Electrolytes lead to: Infection Renal Shutdown Circulatory shock Skin (mechanical)barrier lost Immune system depresses Slide 4.25 3
Rule of nines diagram Used to estimate the % extent of skin burned so doctors will know how much fluid to replace for rehydration to prevent Circulatory shock Renal failure Need to memorize & be Partial Thickness Burns First-degree burns Only epidermis is damaged Local redness, swelling, & pain Usually heal in 2-3 days (short time period) with NO scarring able to use Slide 4.27 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 Slide 4.27 4
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 1 st & 2 nd 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 Slide 4.27 5
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 Athlete s Foot Itchy, red, peeling condition between toes, resulting from fungal infection Cold Sores small fluid-filled blisters that itch & sting Caused by herpes simplex virus 6
Skin Homeostatic Imbalances Infections and allergies Contact dermatitis Exposures (ie. Poison ivy)cause allergic reaction Itching, redness & swelling of skin, progressing to blistering Slide 4.24 Impetigo Caused by bacterial infection Pink, water-filled, raised lesions develop a yellow crust & rupture usually around mouth/nose Highly contagious Cause is unknown Triggered by trauma, infection, stress Psoriasis Reddened epidermal lesions covered w/dry, silvery scales 7