19. Skin Pathology Flashcards
What is the name of the APCs within the epidermis?
Langerhan’s cells
What is the origin of melanocytes?
Neural crest
What is the function of melanocytes?
Produce melanin which they transfer to adjacent squamous cells
Protects nuclei of squamous cells from UV damage
What name is given to moles?
Melanocytic naevi
Why is a basal cell carcinoma called that?
Neoplasm is of small dark cells that look like basal cells in the epidermis
What does ‘palisading’ refer to in a basal cell carcinoma?
Cells and nuclei are arranged parallel
What is a basal cell carcinoma that erodes local structures known as?
‘Rodent ulcer’
What is a specific feature of squamous cell carcinomas?
Keratin production
What risk factors are associated with an increased risk of non-melanoma skin cancer?
Skin type UV exposure Age Radiation treatment Immunosuppression Rarely genetic
What type of NMSC is an immunosuppressed person more likely to get?
Squamous cell
What is Marjolin’s ulcer?
SCC found at the edge of old scars, burns and ulcers
What are genetic causes of SCCs?
Albinism
Xeroderma pigmentosum
Name a genetic cause of BCC?
Basal cell naevus syndrome
What are dysplastic epidermal lesions?
Squamous lesions that show dysplasia
Give 2 examples of dysplastic epidermal lesions
actinic/solar keratosis
Bowen’s disease
What is actinic keratosis?
Often seen in elderly
Epidermis shows dysplasia in sun exposed areas
What is Bowen’s disease
In-situ SCC in non-sun exposed sites
How are NMSCs treated?
Surgical or dermabrasion (AK) Cryotherapy Topical treatment appraise other lesions Moh's micrographic surgery
What’s is Moh’s micrographic surgery?
Small pieces of tumour taken out until margins are clear
What is an ephelis?
Freckle
Localised area of increased melanin production
What is a benign lentigo?
Flat lesion with increased numbers of melanocytes in basal layer
What is a melanocytic naevus?
Clonal proliferation of melanocytes in nests
Evolves over time
What is a naevus?
Hamartoma of a skin element
Found at birth or early in life
Where can malignant melanoma arise apart from skin?
Eye
Meninges
Mucosa
Genitourinary tract
Melanomas can also be non-pigment producing. T/F?
True: amelanotic
What are satellite nodes?
Malignant melanoma spreads within the skin
Where do malignant melanoma mets commonly go?
Liver, lung, brain
What is the difference between Breslow thickness and Clarke’s level of invasion?
Breslow measures the thickness of the lesion
Clarke measures the layer of skin
What are the histological classifications of malignant melanoma?
Superficial spreading
Nodular
Acral
Lentigo maligna
Where is acral melanoma found?
Palms and soles
What is lentigo maligna?
Flat, irregular, pigmented lesion
Caused by proliferation of atypical junctional melanocytes
Chronic sun exposed skin (faces of elderly)
Can evolve to in situ malignant melanoma
How are pigmented lesions assessed?
Dermoscopy
Why should suspected melanoma not be shaved, punched or incised?
Could cause an in situ melanoma to break the basement membrane
When should a sentinel node biopsy be done?
Only when the node is clinically involved
What is the target of Vemurafenib?
B-RAF
What is the target of Ipilimumab?
CTLA-4
