Tumors Flashcards
What is the most common pigmented lesion in lighter skinned individuals?
Ephils/freckles
What is the most deadly skin cancer?
melanoma
What is the most common malignant skin tumor?
basal cell carcinoma
What are ephils?
(appearance and histologic features)
Ephils = freckles
hyperpigmented macule, darkens with sun exposure
increased melanosomes** (normal melanocytes)
Where and in what populations are ephils most commonly seen?
lighter skin
What is lentigo?
(appearance and histologic features)
benign melanocyte hyperplasia
darkened macule/papules (do not change w/ sun exposure)
linear (lentiginous) spread of melanocytes above the basal layer
Where and in what populations is lentigo most commonly seen?
No preference for race, gender, or age
frequently begins in childhood and progresses throughout lifetime
What are nevi?
(appearance)
nevus = mole
benign melanocyte neoplasm
uniformly darkend macule/papule, well defined borders , typically <6mm (opposite of ABCDE of melanoma)
What are the histologic features/types of nevi?
Junctional nevi:
- nest of cells along dermoepidermal junction in the epidermis
- macule (flat) > papule
- most common in children
Compound nevi:
- growth of nests through junction into dermis
- papule (raised) > macule
Intradermal nevi:
- loss of epidermal component, only dermal now; nests -> cords
- papule (raised) > macule
- most common in adults
General progression:
junctional -> compound -> intradermal
Blue nevi:
- black/blue; non-nested; dendritic; fibrosis
- commonly mistaken as melanoma
What are dysplastic nevi?
(appearance and histologic features)
(significance of frequency)
potential precursor of melanoma
- darkend macules; “pebbly” surface; darker, raised center with lighter irregular periphery
- more in line with ABCDE of melanoma
- coalesced nests
- fibrosis of Rete ridges
How do nevi relate to melanoma?
What non-skin cancer are they also associated with?
Dysplastic nevi are less likely to develop into melanoma themselves (although they can) than they are indicative of an increased risk for development of melanoma
Dysplastic nevus syndrome
-autosomal dominant disorder
- 2 or more atypical nevi -or- >100 typical nevi
- associated with 50% incidence of melanoma by age 60
- increased risk of pancreatic cancer
What is melanoma?
(appearance)
malignant melanocyte neoplasm
ABCDE:
- Asymmetry
- irregular Border
- non-uniform Color
- Diameter >6mm
- Evolution
flat or nodular depending on subtype
What are the histologic features/types of melanoma?
(associated prognosis)
Lentigo maligna:
- lentigious growth (radial growth limited to basal layer)
- most common on face of older men
- good prognosis, indolent
Superficial spreading:
-dominant early radial growth
-good prognosis
Acral lentiginous growth:
- lentiginous growth (unrelated to sun exposure)
- can affect mucous membranes, nail beds, palms, and soles
- most common in dark skinned individuals
Nodular:
- dominant early vertical growth
- poor prognosis
Where are the different subtypes of melanoma most commonly seen?
Superficial spreading/nodular:
- sun exposed areas
- backs of men
-extremities of women
Lentigo maligna:
- sun exposed areas
- face of older men
Acral lentiginous:
- independent of sun exposure
- dark skinned populations
- palms, soles, nailbeds, mucous membranes
What are the risk factors for developing melanoma?
- UVB exposure (particulalry severe exposures in childhood rather than cumulative exposure)
- fair skin
- light colored eyes (green/blue)
- dysplastic nevus syndrome (>100 typical or at least 2 atypical)
What is the most important prognostic factor of melanoma?
Breslow thickness:
- depth from granular layer to deepest portion of tumor
- thicker = worse
What is seborrheic keratosis?
(appearance and histologic features)
benign squamous proliferation
- discolored, coin-like, waxy plaques
- uniform color
- spontaneously arise
- keratin pseudocysts
Where and in what populations is seborrheic keratosis most commonly seen?
elderly
-trunk, extremities, head, neck
What is Leser-Trélat sign?
sudden eruption of multiple seborrheic ketaroses indicating possible GI carcinoma
What is acanthosis nigricans?
(appearance and histologic features)
Epidermal hyperplasia
- thick, hyperpigmented
- acanthosis (epidermal hyperplasia)
- papilmatosis (hyperplasia of dermal papilae)
Where and in what populations is acanthosis nigricans most commonly seen?
- interignious/flexor surfaces (axila, groin, neck)
- benign versions typically present in childhood and progress into adulthood; diabetics and obese
- paraneoplastic typically in middle aged men
What are the causes of acanthosis nigricans?
Benign:
- obsesity/endocrine (diabetes, Cushing syndrome)
- autosomal dominant inheritance
- drug related (corticosteroids)
Paraneoplastic:
-GI adenocarcinoma
What are fibroepithelial polyps?
Acrochordon/skin tags
What are epithelial inclusion cysts?
Sebaceous cyst/wen
What is actinic keratosis?
(appearance and histologic features)
premalignant epidermal tumor
-hyperkeratosis, possibly resulting in keratin horn
-rough texture
- elastosis (abnormal elastic fibers in dermis)
- parakeratosis (retained nuclei in stratum corneum)
Where and in what populations is actinic keratosis most commonly seen?
- sun exposed areas
- light skinned individuals
- adults (>50)
What are risk factors for deveoloping actinic keratosis?
-sun/UV exposure
-arsenic
What is the prognosis/treatment for actinic keratosis?
- can spontaneously regress
- can persist or progress to squamous cell carcinoma
- cryotherapy or imiquimod to treat (mostly for prevention of progression or aesthetic reasons)
What cancer is actinic keratosis most likely to progress to?
squamous cell carcinoma
What is cutaneous squamous cell carcinoma?
(appearance and histologic features)
Malignant squamous cell proliferation in the skin
- ulcerated nodule, bleeds easily
- pink keratin pearls
Where and in what populations is cutaneous squamous cell carcinoma most commonly seen?
- typically on face (on or below lower lip)
- sun exposed areas
- more common in men
- leg lesions more common in women
- older adults
-work involves prolonged sun exposure
What are risk factors for developing cutaneous squamous cell carcinoma?
- sun/UVB exposure (cumulative)
- albinism
- xerderma pigmentosum
- arsenic
- immunosupression
What is the prognosis/treatment for cutaneous squamous cell carcinoma?
Good prognosis
-slow growing, rarely metastasizes
Excision to treat
What is Bowden’s disease?
(appearance and histologic features)
Cutaneous squamous cell carcinoma in situ
premalignant squamous cell carcinoma
- erythematous, scaly plaque
- full thickness of epidermis, but basement membrane intact
What is basal cell carcinoma?
(appearance and histologic features)
Malignant basal cell proliferation
-“pink pearly papule” with umbilication
-telangectasias
- palisading (outer cells nuceli are aligned)
- separation artifact (mass seperates from surrounding tissue when sectioned)
Where and in what populations is basal cell carcinoma most commonly seen?
- sun exposed areas (on or above upper lip)
- most common tumor of eyelid and nose
- older adults
- work involves prolonged sun exposure
What are risk factors for basal cell carcinoma?
- sun/UVB exposure (cumulative)
- albinism
- xerderma pigmentosum
- immunosupression
What is the prognosis/treatment for basal cell carcinoma?
Excellent prognosis
-slow growing, rarely metastasizes
excision to treat
Mutations in what pathway are associated with basal cell carcinoma?
SHH pathway:
- PTCH (receptor for SHH), complexed with SMO (inactivating SMO) when not bound by SHH
- SMO, activates transcription enhancing growth and division
Most common mutation is in PTCH preventing it from forming complex with SMO, leading to unregulated cell proliferation
What is dermatofibroma?
(appearance and histologic features)
Benign fibrous histiocytoma
- firm, tan/brown papule
- possibly tender
- well-defined, non-encapsulated mass in the dermis
What is a characterisitc and diagnostic feature of dermatofibroma?
Dimple sign:
-central dimple appears when lesions is pinched
What is a common feature in the history of those with dermatofibroma?
past trauma at the location of the lesion
Where and in what populations is dermatofibroma most commonly seen?
legs of women
What is the prognosis/treatment for dermatofibroma?
asymptomatic, slow growing, benign
no treatment requred
What is dermatofibrosarcoma protuberans?
(appearance and histologic features)
primary fibrosarcoma of the dermis (malignant)
- firm nodule with possible ulceration
- “pinwheel” or storiform fibroblasts
- extends into subcutaneous fat -> “honeycomb” pattern
What is the prognosis/treatment for dermatofibrosarcoma protuberans?
- malignant, rarely metastasize
- extension into subcutaneous fat allows for recurrence
- wide excision to treat (wide to prevent recurrence)
What is mycosis fungoides?
(appearance and histologic features)
Cutaneous T-cell lymphoma
- early pruritic red-brown scaling patches/plaques (resemble psoriasis)
- progress to fungating nodules
- small clusters of CD4+ T cells with cerebriform nuclei in the epidermis-> Pautrier microabsesses
Where and in what populations is mycosis fungoides most commonly seen?
- initialy located on trunk, can later spread elsewhere
- adults, over the age of 40
What is the prognosis/treatment for mycosis fungoides?
Prognosis varies depending on progression
- more lesions/systemic spread (Sezary syndrome) = bad
- nodular lesions = bad
- topical cortiocosteriods, UV therapy (early treatment)
- chemotheraputics (late treatment)
What is mastocytosis?
(appearance and histologic features)
proliferation of mast cells in the dermis (urticaria pigmentosa)
-red-brown papule/plaque
Where and in what populations is mastocytosis most commonly seen?
extremities, trunk, or face (less common in sun exposed places)
cutaneous lesions (90%): children
systemic (infiltration of orans as well) (10%): adults
What are common features/signs of mastocytosis?
Darier sign:
-formation of wheals (dermal edema and erythema) from rubbing of skin
Dermatographia:
- wheals from stroking skin with pointed object
- able to “write” on skin with resulting swelling
What is the prognosis/treatment for mastocytosis?
Cutaneous (children):
-frequently resolves before puberty; good prognosis
Systemic (adults):
-possible poor prognosis
no cure, only supportive treatment
