Dermatology/ Skin Cancer Flashcards
In the evaluation of a suspicious lesion, what does the acronym “ABCDE” stand for?
Asymmetry
Border irregularity
Color variegation
Diameter >6 mm
Enlargement or elevation
What does the sun protection factor (SPF) indicate?
Measures the time a product protects the skin against burning. If you burn after ten minutes without protection, then wearing sunscreen of SPF 15 will theoretically allow you to stay in the sun 15 times longer before burning.
How should people protect their skin from the sun when outside?
- use sunscreen of SPF 15 or greater
- wear hats, shirts, and pants when possible(haha)
- avoid being outside between 10 AM and 4 PM
How long before sun exposure should patients start applying chemical sunscreens?
30 minutes
What is the most common form of skin cancer?
Basal cell carcinoma (BCC)
What are the risk factors for BCC?
- UV exposure
- fair skin
- individual susceptibility
- previous radiotherapy
- basal cell nevus syndrome
- xeroderma pigmentosum
- arsenic ingestion
What is the most common subtype of BCC?
Nodular-ulcerated (60%)
Where does Nodular-ulcerated BCC typically present?
On the face
What is the second most common subtype of BCC?
Superficial (30%)
Where does Superficial BCC typically present?
On the trunk
In what age group does the incidence of BCC peak?
60-70 year olds
What is the most common presentation of a BCC?
Shiny, pearly, or translucent nodule with telangiectasia
What are other skin findings that would make you concerned for BCC?
- Sore that won’t heal
- red, itchy patch
- elevated area with crusting
- waxy area with tight, shiny skin
What are the treatment options for BCCs?
- 95% cured by simple excision or curettage and electrodesiccation
- Recurrent lesions treated with Mohs micrographic surgery.
A scaly, crusted, “sandpaper-like” slightly elevated spot on sun-exposed skin that has appeared and disappeared and now reappeared in a 65-year-old male is most likely what lesion?
Actinic keratosis (AK)
What percentage of cases of actinic keratosis progress on to squamous cell carcinoma?
5%
What is the name and implications of an actinic keratosis on the lip?
Actinic cheilitis can develop into aggressive squamous cell cancer
What is the treatment of actinic keratosis?
- curettage
- liquid nitrogen
- topical 5-fluorouracil for 3-4 weeks
- trichloracetic acid
An open sore that will not heal is most characteristic of what form of skin cancer?
Squamous cell carcinoma (SCC)
Both ultraviolet A (UVA) and ultraviolet B (UVB) radiation from sun exposure increase the risk of SCC. True or false?
True
Which type of ultraviolet light is emitted in tanning beds?
UVA
What are some of the risk factors for the development of SCC?
- chronic sun exposure
- individual susceptibility
- skin damage from burns
- radiation
- chronic irritation
- chemicals
What is the treatment of SCC?
- curettage and desiccation if less than 1 cm
- excision with frozen section control
- Mohs surgery
- radiotherapy
What is the name of the SCC variant that consists of scaly, localized, slow-growing plaques associated with an increased risk of internal malignancy?
Bowen disease
What are the four types of melanoma?
- Superficial spreading (70%)
- Nodular
- Acral lentiginous
- Lentigo maligna
What type of melanoma is most likely to metastasize?
Nodular melanoma
What lesion presents as a rapidly enlarging vascular lesion following minor trauma, and is commonly confused with nodular melanoma?
Pyogenic granuloma
An African American male presents with a painless, dark brown discoloration under his toenail and on the sole of his foot. What is the most likely diagnosis?
Acral lentiginous melanoma
Where on the body are most melanomas located?
Trunk and legs
What is the major determinant of prognosis in melanoma?
Level of invasion (Clark level or Breslow thickness)
What is the treatment of melanoma?
- excision with sentinel node biopsy if more than 1 mm deep
- chemotherapy if metastatic
What follow-up is needed after diagnosis of any type of skin cancer?
Check for development of new lesions every 3-6 months
