Skin Cancer Flashcards
(Canadian #s) skin cancer accounts for about ____ of cancer diagnosis
1/3
what are the 3 common types of skin cancer
- Basal cell carcinoma (highest prevalence)
- squamous cell carcinoma
- malignant melanoma (lowest prevalence and the worst)
skin cancer can be _______ & starts with ______ lesion
skin cancer can be avoided & starts with precancerous lesion
what is the precancerous lesion called?
actinic keratosis
what is the etiology of skin cancer
- excessive exposure to sun (UV ligh -UVA & UVB)
- cumulative skin exposure - proportional directly to age (the older you get the more likely you are to get skin cancer)
- inversely proportional (as one goes up one goes down): melanin (protective factor) decreases risk (more melanin less likely to get skin cancer)
skin cancer has a ____% cure rate if detected and treated early
95
Basal cell carcinoma
- most common
- begins in basal layer
- common type in light skin
- basal cell origin
- slow progression
- local invasion if left untreated, but rarely metastasizes
- on exposed areas to sun: mostly head & neck
- begins as nodular lesion
- biopsy for Diagnosis
Malignant melanoma
- arise in melanocytes (melanocytes produce melanin which is pigment)
- increase risk in fair skin (more melanin means less skin cancer risk)
- worst form: -progresses rapidly
- mets (easily & early) - mostly exposed but also non exposed surfaces (major lesions changes (mnths)):
- doubling in size (3-8 mnths)
- colour
- irregular border
- pruritus
- crusting
- ulceration - mets to brian, bone, lung, liver (reason for fatality is because of metastasis) can be fatal, curable if caught early
squamous cell carcinoma
- 2nd most common
- origin in keratinocytes
- on exposed areas: nose, forehead, lower lip
- intraepidermal & invasive types
- faster progression
- variable appearance of lesion ex.nodule, papules, ulcerative lesions
- mets: -to local lymph nodes & via blood
- if treated early 95% cure rate, if left than metastasizes 75% mortality rate
basal cell carcinoma & squamous cell carcinoma collectively combined account for ____% of skin cancer
90
what kind of cells does basal cell carcinoma originate in?
-basal cell origin
what kind of cells does squamous cell carcinoma originate in?
-origin in keratinocytes
what kind of cells does malignant melanoma originate in?
-origin in melanocytes
what is the general rule for detecting skin cancer
any suspicious change to a lesion should be investigated, better to be told it is not a malignancy then it is a malignancy & dont know
treatment of skin
- early detection
- Sx excision (in all cases)
- AND chemo if systemic (spread to secondary site)