- Antigen recognition
- Involved in contact hypersensitivity
- Sensory mechanoreceptors.
- Merkel cell carcinoma presents as red/purple papulo-nodule.
- A neuroendocrine tumor with staining for neuron specific enolase and neurofilament protein.
Glomus cell tumor:
- Painful, subungal tumor
- From glomic end organ
- Tx: shell out
- Involves apocrine glands, therefore see after puberty in axilla, groin
Basal cell CA: 4:1 more common than SCC
- BCC has peripheral palisading of nuclei on pathology.
- Glistening and Pearly appearance.
FTSG: contracts less than STSG
STSG: Donor site regenerates from hair follicles, skin appendages.
- STSG blood supply by imbibition 1st few days, then neovascularization days 2-7 (capillary ingrowth)
Flap necrosis: most commonly due to venous thrombosis
Melanoma 4 types:
- Nodular (worst, early mets)
- Superficial spreading
- Lentigo maligna
- Acral lentiginous
Risks for melanoma:
- Dysplastic nevi
- Congenital nevi
- Mole syndrome (100% risk)
- Skin > eyes > rectum
- #1 skin site for men is back, in women is legs
Worse Px if on BANS: back, arms, neck, scalp
Melanoma excision Margins:
- Depth <1mm: 1 cm
- Depth 1-4mm: 2 cm
- Depth >4mm: 3 cm
- <0.75mm (90%cure)
- 0.75 to 1.65mm
- >4mm (80% distant metastasis)
- Extends beyond wound margins
- Failure of collage breakdown and increase collagen production.
Hypertrophic scar: Does not extend beyond margins.