Pigmented lesions condensed Flashcards
these are entirely dermal and consist of pigment rich dendritic spindle cells. The cellular variant may have mitoses and mimic melanoma
Blue naevi
Dendritic spindle cells in which type of naevi?
Blue naevi!
Halo naevi are overun by which type of cell?
lymphoctyes
have a peripheral halo of depigmentation. They show inflammatory regression and are overrun by lymphocytes
Halo naevi
Dendritic spindle cells?
Blue naevi!!
Consist of large spindle and/or epithelioid cells
Spitz naevi
Problems with spitz naevi?
May closely mimic melanoma
Most are entirely benign
Difficult area as there is a malignant variant!
Colour of spitz naevus?
Pink/red due to prominent vascularisation
Commonest site for superficial spreading melanoma?
Trunk and limbs
Commonest site for nodular melanoma?
Varied sites but often trunk
Commonest site for acral/mucosal melanom?
Acral and mucosal duh
Commonest site for lentigo maligna?
Sun damaged face/scalp
How to recognise superficial spreading melanoma?
Looks like a well dodgy flat brown patchy patch with different colours
AREAS of REGRESSION!! i.e. may also have paler splotches within it!
Why is nodular melanoma different?
No radial growth phase!! (RGP)
Only VGP
Breslow thickness
Deepest tumour from granular layer mm
Strong adverse indicator for melanoma prognosis?
Ulceration
High mitotic rate, lymphovascular invasion, satellites, sentinel lymph node involvement
Suffix b indicates what
Ulceration
Satellite
Satellite lesions are small nodules of tumour/melanoma located more than 0.05mm from the primary lesion, but less than 2cm
Hoe does malignant melanoma spread?
1) Satellite deposits of MM
2) Regional lymph node metastases
3) Blood spread (skin/soft tissue, heart, lungs, GI tract, Liver, Brain)
Treatment for melanoma?
Primary excision to give clear margins
Some also receive a sentinel node biopsy
If SN positive - regional lymphadenectomy
Treatment of advanced disease difficult
Chemo, immunotherapy, genetic therapies
If in situ-clear by
5mm
If invasive but less than 1mm thick, clear by
1cm
If invasive and more than 1mm thick, clear by
2cm
When would you do SNB?
If >1mm thick or thinner with mitoses
SNB = sentinel node biopsy
Imatinib
Acral melanomas (c-kit mutation)
Dabrafenib and vemurafenib interfere with which pathway?
MEK/ERK pathway
(BRAF)
-some melanomas on intermittendly sun-exposed skin may have a BRAF mutation
Difference between ephilides and lentigines?
Lentigines do not darken following sun exposure
Increased basal melanocytes (nests) with downgrowths at dermo-epidermal junction
Navei
Acquired melanocytic naevi?
Junctional
Compound
Intradermal
How do congenital melanocytic naevi differ from acquired naevi?
Larger, slightly raised
Become more rugose and elevated as child grows older
Increased risk of melanoma in large naevi
In atypical naevus syndrome, how does your risk of melanoma increase?
Increases by 2 if you have 2
Increases by 6 if you have 6
Dermoscopy of melanoma
atypical pigment network, black dots, irregular streaks,
focally a blue-whitish veil and a white regression zone with hairpin vessels
Most common subtype of melanoma?
Superficial spreading
Increased melanoma in asian and african people?
Acral lentiginous melanoma
Hutchinson sign
Pigmented excision into the nail fold
ACRAL MELANOMA
Stuck on appearance
Seborrhoeic keratoses
very common
older Caucasians
brown / black
greasy lesions
often on trunk
usually multiple
“stuck-on” appearance
often “warty” but may be flat
regular border
may detach spontaneously or
in part
Seborrhoeic keratoses
Talon noir
Black heel due to haematoma
-caused by trauma
