Derm & Plastics Flashcards
1
Q
Gene defect in hereditary melanoma
A
CDKN2A - codes for p16, regulates cell cycle
2
Q
Graft failure causes
A
Infection
Inadequate graft bed
Graft damage
Separation of graft from bed (e.g. Seroma, haematoma)
Shearing (mobile graft, cannot revascularise)
3
Q
What is naevus
A
Benign proliferation of normal constituents of skin
4
Q
ABCDE of melanoma
A
Asymmetry Border irregularity Colour change/variation Diameter >6mm Evolving features (shape/size/colour)
5
Q
Management of ?melanoma
A
- Excisional biopsy with 2mm margin
- Sentinel LN mapping
- Block dissection of lymph nodes
6
Q
Breslow thickness
- Where it’s measured from
- Figures on prognosis (5 year survival)
A
- Upper layer of epidermis to deepest point of tumour penetration
- 1 and 4 (4=H which is high risk)
<1mm: >95%
1-2mm: 80-95%
2-4mm: 60-75%
>4mm: 50%
7
Q
Pathological features of melanoma
A
Initially spread radially, then vertically when it had more malignant potential.
Spread via lymphatics to LNs first, and then haematogenous to organs at later stage.
Lymphocytic infiltrate associated with better prognosis.
8
Q
SCC management
- Poor prognostic indicators
A
- Excision biopsy
- Radiotherapy - very responsive to this. RTx to LNs
- Large tumours >2cm, recurrent lesions, pre-existing scars, skin/ear/lip/scrotum
9
Q
BCC treatment options
A
- Cryotherapy
- Topical chemo: 5-FU, Imiquimod
- Curettage and cautery +/- graft/flap
- Photodynamic therapy. 5-ALA absorbed into tumour cells, converted to photosensitive porphyrin, which destroys cells when exposed to light of wavelength 600-700nm. (Also used for solar keratosis)
10
Q
Margins of resection for melanoma
- Excision biopsy
- Excision for curative intent
A
- 2mm margin
- <1mm, at least 1cm margin
1-4mm, 2cm margin
11
Q
Clark’s levels
A
- Limited to epidermis (in situ)
- Papillary dermis
- Papillary/reticular dermis junction
- Reticular dermis
- Subcutaneous fat
