where do basal cell carcinomas come from
stratum basale
what does the stratum spinosum have
prickle cells/acanthocytes
what are the majority of the cells in the stratified sqamous epithelium
stratum spinosum
what is stratum lucidum prominent in
thick skin (clear zone)
should the stratum corneum have nuclei
no just layers of keratin
what are the keratinocyte layers in order
basale
spinosum
granulosum
lucidum
corneum
what are the cells of the epidermis not the keratinocytes
melanocytes
langerhans cells
merkel cells
what are the appendages in the epidermis
hair follicles
sebaceous gland
eccrine
apocrine
what are the dermis' areas
papillary
reticular
what are the APCs of the skin
langerhans cells
what are the merkel cells of the skin
neuroendocrine cells
what is another name for the hair follicle
pilosebaceous apparatus
what part of the dermis inter-reticulates wit the epidermis
papillary dermis
what does the reticular dermis have a lot of
reticular fibers
what is vitilligo
lack of pigmentatino
what do xanthomas relate to
hypercholesterolemia and hyperlipidemia
what are all the areas here
there you go
are epithelial layers named by the bottom layer or top laeyr
top (stratified squamous instead of stratified columnar)
what connects stratum spinosum to one another
tonofibrils
where does keratin begin in the skin
granulosum
what is true of stratum corneum in thick skin
it is thicker than the rest of the layers
where is the langerhans cell
boom
where are there eccrine sweat glands
everywhere
where are apocrine sweat glands
axilla and groin
what type of things are included in apocrine sweat
protein
what is a macule and what is a papule
flat lesion
bumpy lesion
what is a macule
circumscribed lesion of <5mm in diameter characterized by flatness and usually disoclored
what is a patch
circumscribed lesion of >5mm in diameter characterized by flatness and usually disoclored
what is a papule
elevated dome shaped or flat topped lesion <5mm acrooss
what is a nodule
elevated lesion with spherical contour >5mm across
what is a plaque
elevated flat topped lssion, usually >5mm across
what is a vesicle
fluid filled raised lesion <5mm across
what is a bulla
fluid filled raised lesion >5mm across
what is blister
common term used for vesicle or bulla
what is a pustule
discrete, pus-filled, raised lesion
what is a wheal
itchy, transiet, elevated lesion with variable blanching and erythema formed as a result of dermal edema
what is a scale
dry, horny, plate-like excrescence usually the result of imperfect cornification
what is lichenification
thickened and rough skin characterized by prominent skin markings, usually the result of repeated rubbing in susceptible persons
what is excoriation
traumatic lesion characterized by breakage of the epidermins causing a raw linear area
what is onycholyssi
separation of nail plate from nail bed
what is hyperkeratosis
thickening of stratum corneum, often associated with a qualitative abnormality of the keratin
what is parakeratosis
modes of keratinization characterized by the retention of the nuclei in the stratum corneum; on mucus membranes, parakeratosis is normal
what is hypergranulosis
hyperplasia of the stratum granulosum, often due to intense rubbing
what is acanthossi
diffuse epidermal hyperplasia
what is papillomatosis
surface elevation caused by hyperplasia and enlargement of contiguous dermal papillae
what is dyskeratosis
abnormal keratinization occuring prematurely within individual cells or groups of cells below the stratum granulosum, generally the same as dysplasia
what is acantholysis
loss of intercellular connection resulting in loss of choesion between keratinocytes
what is spongiosis
intercellular edema of epidermis
what is hydropic swelling (ballooning)
intercellular edema of keratinocytes
what is exocytosis
infiltration of the epidermis by inflammatory or circulating blood cells
what is erosion
discontinuity of the skin exchibiting incomplete loss of epidermis
what is ulceration
discontinuity of the skin exhibiting complete loss of the epidermis and often of portion of the dermis and even subcutaneous fat
what is vacuolization
formation of vacuoles within or adjacent to cells; often refers to basal cell basement membrane zone area
what is lentiginous
referrring to a linear pattern of melanocyte proliferation within the epidermal basal cell layer; lentiginous melaocytic hyperplasia can occur as a reactive change or as part of a neoplasm of melanocytes
what is the skin defined as
keratinized stratified squamous epithelium with skin appendages
what other places in the body have stratified squamous epithelium
esophagus and cervix
what other part of the body also has keratinized stratified squamous epithelium
hard palate
what are some pigemtnation disordres
vitiligo
freckles (ephelis)
melasma
lentigo
nevus
dystplastic nevus
malignant melanoma
what is this
vitiligo
what would also behave like vitiligo but would clear up
post=inflammatory hypopigmentation
what is going on here
melasma
what is another name for melasma
mask of pregnancy
what is lentigo
brown pigmented spont on the skin, a benign hyperplasia of melanocytes taht is linear in its spread
what is this
lentigo
would lentigo be palpable
no
what is this
lentigo
will lentigo be palpable
no
what are the main things to differentiate nevi from melanomas
junctional (more pigmented, more closely associated with melanoma
intra dermal
compound
do nevi have to be hyperpigmented
no
what is this
intradermal nevus
what is this
intradermal nevus
note the lack of "junctional activity"
why is the above nevus not pigmented
mostly by the epidermal/dermal jucntion
what is this
junctional nevus
what is this
junctional nevus
what would a compound nevus be
both junctional and intradermal
what are most of the things that are confused with malignant melanoma
junctional nevi
what is malignant melanoma related to
sun
what is the only primary skin cancer that can kill you (except rare merkel cell tumor)
malignant melanoma
what growth phases exist in malignant melanoma
both vertical and horizontal
what is prognosis of malignant melanoma related to
vertical growth, breslow staging, TNW
is it difficult to differentiate malignant melanomas from nevi clincally and microscopically
yes
what are malignant melanoms a proliferation of
melanocytes
what is this
malignant melanoma
what is teh ABCDEFG principle of malignant melanoma
asymmetry
borders (irregular)
color (variegated)
diameter (greater than 6 mm)
evolving over time
NODULAR MELANOMA
elevated above the skin surface
firm to the touch
gorwing
what is this
malignancy: ipgment is MELANIN
what are the benign epidermal tumors
seborrheic keratosis
acanthosis nigricans
fibroepithelial polyp (skin tag
epidermal cyst
adnexal tumors: eccrine, apocrine
keratoacanthoma
what is this
saborrheic keratosis
what is this
seborrheic keratosis
what is this and what are the circles
seborrheic keratosis
horn cysts
what is this
acanthosis nigricans
what is this
acanthosis nigricans
what is acanthosis nigricans associated with
diabetes mellitus
where are the skin folds in acaanthosis nigricans
axilla, neck
what is this
fibroepithelial polyp/skin tag
what is this
fibroepithelial polyp
CT with dermis covered by skin that pops up
what is this
epidermal inclusion cyst
what is this
epidermal inclusion cyst
what are adnexal tumors
hair follicles
sebaceous glands
sweat glands (eccrine, apocrine)
are adnexal tumors malignant
no, almost all benign
what is the main lesion to differentiate from SCC
keratoacanthoma
what is this
keratoacanthoma
what is ithis
keratoacanthoma
what is this
keratoacanthoma
what is a collarette
classical feature which differentiates KAs from SCCs
looks like a volcanic crater
what is included in the premalignant/malignant skin cancers
actinic keratosis
SCC
BCC
merkel cell carcinoma
what is the precursor to SCC
actinic keratosis
which skin cancer shows "pearls"
SCC, also shows intercellular bridges
what are the most common premalignant/malignant skin cancers
BCC
what skin cancer is associated with BCC
blue palisading nests
what does merkel cell carcinoma look like
small cell carcinoma of the lung
what is "farmer's ear"
BCC
are BCCs and SCCs releated to the sun
yes
what is SCC related to
As, carcinogens, chaw, betel nut, HPV
what type of damage do both SCC and BCC do
local damage, rarely mets or kill
what do merkel cells act like
melanomas
what is this
actinic keratosis
what is this
actinic keratosis
what does actinic keratosis lead into
SCC in situ of skin (bowen's disease)
what is this
SCC
what is the name for SCC IS
Bowen's disease
does SCC have a collarette
no
what is this here
SCC
PEARLS: well differentiated
what is this
squamous dysplasia
maybe actinic keratosis leading into SCC
what is the most common malignancy of skin
BCC
what do stratum basale cells look like they are doing
palisading
what are the classic BCC places
behind ear and on nose
what is this
BCC (note peripheral palisading)
why are BCCs blue
because bassl cells have a greater percentage of nucleus to cytoplasm
what is this
merkel cell tumor
is a merkel cell tumor rare and usually malignant
yep
what does MCC look like
small cell carcinoma of the lung
what are the dermis tumors
dermatofibroma
dermatofibrosarcoma protuberans
malignant fibrous histiocytoma
xanthmoa
vascular tumors
why are there no fibromas in dermis tumors
because tumors of pure fibroblasts of the dermis are rare
what is this
benign fibrous histiocytoma or dermatofibroma
what is this
benign fibrous histiocytoma or dermatofibroma
what is this
malignant fibrous histiocytoma
what is this
xanthoma
what are xanthomas filled with
cholesterol and lipids
is this a malignant tumor
no: xanthoma filled with cholesterol and lipids
what is this
hemangioma
what are hemangiomas
congenital birth marks that can regress with againg
what is a red lesion that blanches when you put pressure on it suspected to be
vascular tumor
what is this
Kaposi's sarcoma
what causes kaposi's sarcoma
HHV 8
what might you have to do for kaposi's sarcoma
factor 8 stain
what are some some cellular "immigrants" in the skin cancers
langerhans cells (histiocytosis)
mycosis fungoides (T cell cutaneous lymphoma)
mastocytosis (mast cell tumors)
what is this
ichthyosis
what is often common in icthiosis
lamellar
what are some acute dermatoses
urticaria
eczema
erythema multiforme
what are some chronic dermatoses
psoriasis
seborrheic dermatitis
lichen planus
lupus erthymatosus
what are dermatoses
inflammatory skin diseases
can dermatoses be diagnosed just looking at microscope slide
nope
what is urticaria
dermal edema
what happens in urticaria
dilation of vascular spaces
early perivascular cuffing of inflammatory cells
what is urticaria synonymously used with
type I hypersensitivity
what is this
urticaria (hives)
what is the classic skin response to type I hypersensitivity
urticaria
what is eczema
myriad of acute inflammatory disorders with allergic, drug related, sun related etiologies
what is the common histologic feature of eczema
spongiosis
what if there is a rash that is both flat and bumpy
maculopapule rash
what is spongiosis
intercellular edema of epidermis
what is this
eczema (keratinocytes on the right are more spread out)
what is seen here
pustules (extreme spongiosis)
- if just water: blister/bulla
what are these
ulcerated pustules
what is this
erythema multiforme
what is erythema multiforme due to
unknown cause, possibly mediated by deposition of immune complex (IgM) in superficial microvasculature of skin and oral mucus membrane that usually follows an infection or drug exposure
what could erythema multiforme be related to
extreme urtricaria
how much of US has psoriasis
1-2%
where is psoriasis most common
elbows, knees
what is keratosis really
parakeratosis, genrealized epidermal hyperplasia, elongation of rete pegs, extensive chronic inflammatory cell infiltrates, munro intraepidermal microabscesses
what is going on here
classical psoriasis
what is this and what is it common in
seborrheic dermatitis
HIV
what disease cause pigmentary incontinence
lichenoid disorders
via melanophages, NOT melanocyte
what happens in lupus
antibodies vs. DNA
what is this
stasis dermatitis
what is this
stasis dermatitis
is purple stasis dermatitis more severe
yes
what is this
stasis dermatitis
what is this
stasis dermatitis
what will stasis dermatitis show
hyperpigmented lesions and can vary in severity (ulcerations even)
most common in places that are vulnerable to arterial ischemia
what are bullous diseases
pemphigus (vulgaris)
bullous pemphigoid
dermatitis herpetiformis
epidermolysis bullosa
porphyria
acantholysis
what is the common unifying finding of the bullous diseases
acantholysis
basement membrane immunoglobulins
what is a bulla
fluid filled raised lesion greater than 5 mm across
what is acantholysis
loss of intercellular connections resulting in loss of cohesion between keratinocytes
what is this
pemphigus, fresh bullae
what is this
pemphigus, ruptured and scabbed bullae
what is happening here
acantholysis in the bullous family of diseases
what are the "acanthocytes" of the skin
stratum spinosum
where can separation be in acanthosis
stratum spinosum or dermal/epidermal junction
what are many of the bullous diseasae disesaes of
basement membrane and tonofibrils
what is the bread and butter of dermatology
acne vulgaris
what is main feature of acne vulgaris
sebaceous duct blockage with secondary inflammation is main feature
what breask down sebaceous oils
propionibacterium acnes, resulting fatty acids act as irritants
what is acne then
folliculitis
whats this
ACNE!
what are two versions of panniculitis
erythema nodosum
erythema induratum
how many causes have an unknown cause of EN
30-50%
what is EN associated
many diseases
TB, strep, myocplasma, yersinia, EBV, coccidiomycosis, sarcoid, IBD, autoimmune, pregnancy, meds, cancers
are there lots of granulomatous disease related to EN
yes
is EI related to some other disease
TB
what is this
EN (red nodules on legs)
what is this
erythema induratum
what is a panniculitis
primary inflammation of the subdermal CT/hypodermis/subcutis
what is this
panniculitis
what are the infectious of the skin
verrucae (HPV)
mulluscum contagiosum
impetigo (staph, strep)
fungi
arthropods
how manay viruses besides HPV can you think of which cause squamous proliferations in ANY part of the body
not many
what is a wart caused by
epidermal proliferations due to virus usually
what is going on here
papillomatous epidermal hyperplasia of WARTS and hypergranulosis at bottom
what type of virus is molluscum contagiosum
pox virus
what is this
molluscum contagiosum
what is this
molluscum contagiosum
how does molluscum contagiosum progress
red to purple to blue
what is this
impetigo
but could be HSV 1 or 2 also
what are the tineas
capitis
barbae
corporis
cruris
pedis
onychomycosis
what species causes the tineas
trichophyton
microsporum
epidermophyton
what have we here
ringworm of scalp: tinea capitis
what is going on here
tinea barbae
what is going on here
tinea corporis
what is going on here
tinea cruris
what is this
tinea pedis
if your patient has a gangrenous toe, which one is most likely
toe 5
what is this
onychomycosis
what is prominent in this histologic slice
hyphae (PAS stain)
what do arthropods do typically
bites
stings
infestations
what scabies are of medical importance
scabies
pediculosis
demodex
ticks, mites
where is scabies most common
knuckles
what is another name for body lice
pediculosis
what is another name for pubic louse
phthrius pubis
where do mite larva like to live
hair follicle/next to hair shaft
why is a mite an arachnid and not an insect
8 legs
what is this
tick