Robbins

Question 1

most common pigmented lesions of childhood in lightly pigmented individuals

Answer 1

Freckle (Ephelis)

Question 2

essential histologic feature is linear (nonnested) melanocytic hyperplasia

Answer 2

lentigo

Question 3

Melanocytic nevi (known colloquially as moles) are common benign neoplasms caused in most cases by acquired activating mutations in ____ and ____

Answer 3

NRAS and BRAF

Question 4

melanocytic nevi which consist of aggregates or nests of round cells that grow along the dermoepidermal junction

Answer 4

junctional nevi

Question 5

event where nevi acquire fusiform contours and grow in fascicles resembling neural tissue

Answer 5

neurotization

Question 6

conventional nevi, frequently have acquired activating mutations in the NRAS and BRAF genes, what are the additional mutations in dysplastic nevi? (2)

Answer 6

CDKN2A and CDK4

Question 7

T/F dysplastic nevi occur only on sun-exposed body surfaces.

Answer 7

False

they occur on both sun-exposed and protected body surfaces

Question 8

most deadly of all skin cancers and is strongly linked to acquired mutations caused by exposure to UV radiation in sunlight

Answer 8

melanoma

Question 9

frequent “driver” mutations in melanoma (3)

Answer 9

Mutations that disrupt cell cycle control genes - CDKN2A

Mutations that activate pro-growth signaling pathways - RAS and PI3K/AKT pathway

Mutations that activate telomerase - TERT

Question 10

most commonly mutated gene identified in melanoma

Answer 10

TERT

Question 11

phase in melanoma growth wherein it still lacks the capability to metastasize

Answer 11

radial growth phase

Question 12

melanoma growth phase during which the tumor cells invade downward into the deep dermis as an expansile mass and is heraleded by the appearance of a nodule

Answer 12

vertical growth phase

Question 13

mutation found in many sporadic seborrheic keratoses and are thought to drive the growth of the tumor

Answer 13

FGFR3

Question 14

Seborrheic keratoses may suddenly appear in large numbers as part of this paraneoplastic syndrome

Answer 14

Leser-Trélat sign

Question 15

marked by thickened, hyperpigmented skin with a velvet-like texture that sometimes appears as a paraneoplatic syndrome usually gi adenocarcinoma

Answer 15

Acanthosis nigricans

Question 16

the familial form of Acanthosis nigricans is associated with germline activating mutations in

Answer 16

FGFR3

Question 17

multiple trichilemmomas are associated with what syndrome?

Answer 17

Cowden syndrome

Question 18

composed of islands of cells resembling the normal epidermal or adnexal basal cell layer (basaloid cells).These islands fit together like pieces of a jigsaw puzzle within a fibrous dermal matrix

Answer 18

cylindroma

Question 19

proliferation of basaloid cells that forms primitive structures resembling hair follicles

Answer 19

trichoepithelioma

Question 20

shows a lobular proliferation of sebocytes with increased peripheral basaloid cells and more mature sebocytes in the central portion that have frothy or bubbly cytoplasm due to the presence of lipid vesicles

Answer 20

sebaceous adenoma

Question 21

composed of basaloid cells that show trichilemmal or hair-like differentiation similar to that seen in the germinal portion of the normal hair bulb in the anagen growth phase

Answer 21

pilomatrixoma

Question 22

shows infiltrative cells with ductal differentiation with prominent decapitation secretion similar to that seen in the normal apocrine gland

Answer 22

apocrine carcinoma

Question 23

most important cause of cutaneous squamous cell carcinoma is

Answer 23

DNA damage induced by exposure to UV light

Question 24

premalignant lesion that occurs in sun damaged skin

Answer 24

actinic keratosis

Question 25

Basal cell carcinoma is a distinctive locally aggressive cutaneous tumor that is associated with mutations that activate the ____ pathway

Answer 25

Hedgehog signaling pathway

Question 26

most common invasive cancer in humans

Answer 26

basal cell carcinoma

Question 27

gene associated with nevoid basal cell carcinoma syndrome (NBCCS) (also known as basal cell nevus or Gorlin syndrome)

Answer 27

PTCH (patched)

Question 28

invasive cords and islands of variably basophilic cells with hyperchromatic nuclei, embedded in a mucinous matrix and often surrounded by many fibroblasts and lymphocytes. The cells at the periphery of the tumor cell islands tend to be arranged radially with their long axes in parallel alignment

Answer 28

basal cell carcinoma, nodular type

Question 29

These tumors consist of benign, spindle-shaped cells that are usually arranged in a well-defined, nonencapsulated mass within the mid-dermis

Answer 29

dermatofibroma

Question 30

best regarded as a well-differentiated, primary fibrosarcoma of the skin. It is composed of closely packed fibroblasts arranged radially, a pattern referred to as storiform. Mitoses are rare. The overlying epidermis is generally thinned. Deep extension from the dermis into subcutaneous fat, producing a characteristic “honeycomb” pattern, is frequently seen

Answer 30

Dermatofibrosarcoma protuberans

Question 31

The molecular hallmark of dermatofibrosarcoma protuberans is a translocation involving the genes __ and ___ and leads to overexpression and increased secretion of ____

Answer 31

COL1A1 and PDGFB, PDGFB

Question 32

Histologic landmark of cutaneous T-cell lymphoma (CTCL) is the presence of atypical cells that characteristically form band-like aggregates within the superficial dermis and invade the epidermis as single cells and small clusters called

Answer 32

Pautrier microabscesses

Question 33

encompasses a spectrum of rare disorders characterized by increased numbers of mast cells in the skin and, in some instances, in other organs as well

Answer 33

mastocytosis

Question 34

Many cases of mastocytosis have acquired activating point mutations in

Answer 34

KIT

Question 35

mass forming increase in mast cells around superficial dermal blood vessels to large numbers of tightly packed mast cells in the upper to mid-dermis

Answer 35

mastocytoma

Question 36

Granules in mast cells may be visualized with

Answer 36

toluidine blue or giemsa

Question 37

X-linked ichthyosis is caused by a deficiency of

Answer 37

steroid sulfatase

Question 38

exhibit a buildup of compacted stratum corneum that is associated with loss of the normal basket-weave pattern and there is generally little or no inflammation

Answer 38

ichthyosis

Question 39

Eczematous dermatitis typically results from this type of hypersensitivity

Answer 39

T cell– mediated inflammatory reactions (type IV hypersensitivity)

Question 40

a lymphoma of skin-homing CD4+ T-helper cells that presents in the skin

Answer 40

mycosis fungoides

Question 41

characterized by keratinocyte injury mediated by skin-homing CD8+ cytotoxic T lymphocytes

Answer 41

Erythema multiforme

Question 42

typical lesion is a well-demarcated, pink to salmon-colored plaque covered by loosely adherent silver-white scale. There is increased epidermal cell proliferation results in marked epidermal thickening (acanthosis), with regular downward elongation of the rete ridges sometimes described as appearing like test tubes in a rack

Answer 42

psoriasis

Question 43

skin layer that is thinned or absent in psoriasis

Answer 43

stratum granulosum

Question 44

In psoriasis the abnormal proximity of vessels within the dermal papillae to the overlying parakeratotic scale accounts for the characteristic clinical phenomenon of multiple, minute, bleeding points when the scale is lifted from the plaque and this is called

Answer 44

Auspitz sign

Question 45

Characteristic of psoriasis is the finding of neutrophils forming small aggregates within the superficial epidermis called _____ and the parakeratotic stratum corneum called _____

Answer 45

spongiform pustules, munro microabscesses

Question 46

a chronic inflammatory dermatosis classically involves regions with a high density of sebaceous glands

Answer 46

seborrheic dermatitis

Question 47

lesions can be induced in susceptible individuals by local trauma, a process known as

Answer 47

Koebner phenomenon

Question 48

Koebner phenomenon can be observed in __ and ____

Answer 48

psoriasis and lichen planus

Question 49

papules of lichen planus are often highlighted by white dots or lines called

Answer 49

Wickham striae

Question 50

Lichen planus is characterized histologically by a dense, continuous infiltrate of lymphocytes along the dermoepidermal junction called

Answer 50

interface dermatitis

Question 51

a blistering disorder caused by autoantibodies that result in the dissolution of intercellular attachments within the epidermis and mucosal epithelium

Answer 51

Pemphigus

Question 52

are functionally interchangeable components of desmosomes but have different distributions within the epidermis (2)

Answer 52

Desmoglein 1 and 3 (Dsg1 and Dsg3)

Question 53

T/F Dsg3 is most abundant in the superficial skin

Answer 53

False, more abundant in the basal layer

Question 54

T/F Dsg1 is most abundant in the superficial skin

Answer 54

True

Question 55

pemphigus type where in autoantibodies against Dsg1 and Dsg3 cause blisters in the deep suprabasal epidermis

Answer 55

pemphygus vulgaris

Question 56

pemphigus type where in autoantibodies target Dsg1 only

Answer 56

pemphigus foliaceus

Question 57

lesions where in autoantibodies bind BPAG2, a component of the hemidesmosomes, leading to blister formation at the level of the lamina lucida of the basement membrane

Answer 57

bullous pemphigoid

Question 58

lesion where in IgA autoantibodies attach to the fibrils that anchor hemidesmosomes to the dermis

Answer 58

dematitis herpetiformis

Question 59

pemphigus associated with various malignancies, most commonly non-Hodgkin lymphoma.

Answer 59

Paraneoplastic pemphigus

Question 60

T/F All forms of pemphigus are autoimmune diseases caused by IgG autoantibodies against desmogleins that disrupt intercellular adhesions and result in the formation of blisters.

Answer 60

True

Question 61

common histologic feature in all forms of pemphigus is

Answer 61

acantholysis

Question 62

identification of subepidermal, nonacantholytic blisters points to

Answer 62

bullous pemphigoid

Question 63

protein target of antibodies in bullous pemphogoid

Answer 63

BPAG2

Question 64

Lesion where in fibrin and neutrophils accumulate selectively at the tips of dermal papillae, forming small microabscesses. The basal cells overlying these microabscesses show vacuolization and focal dermoepidermal separation that ultimately coalesce to form a true subepidermal blister. By direct immunofluorescence, it shows discontinuous, granular deposits of IgA that selectively localize in the tips of dermal papillae

Answer 64

dermatitis herpetiformis

Question 65

blanket term for a group of disorders caused by inherited defects in structural proteins that lend mechanical stability to the skin. The common feature is a proclivity to form blisters at sites of pressure, rubbing, or trauma, at or soon after birth.

Answer 65

epidermolysis bullosa

Question 66

Cutaneous manifestations consist of urticaria and vesicles associated with scarring that are exacerbated by exposure to sunlight. The vesicles are subepidermal in location, and the adjacent dermis contains vessels with walls that are thickened by glassy deposits of serum proteins, including immunoglobulins

Answer 66

porphyria

Question 67

acne type composed of open and closed comedones

Answer 67

non-inflammatory acne

Question 68

stage of rosacea where there is permanent thickening of the nasal skin by confluent erythematous papules and prominent follicles

Answer 68

rhinophyma

Question 69

individuals with rosacea have high cutaneous levels of the antimicrobial peptide ____

Answer 69

cathelicidin

Question 70

inflammatory reaction in the subcutaneous adipose tissue that may preferentially affect the lobules of fat or the connective tissue that separates fat into lobules

Answer 70

Panniculitis

Question 71

is a form of secondary panniculitis caused by self-inflicted trauma or injection of foreign or toxic substances

Answer 71

Factitial panniculitis

Question 72

squamoproliferative lesions caused by human papillomaviruses (HPVs)

Answer 72

Verrucae

Question 73

lesions show cup-like verrucous epidermal hyperplasia.The diagnostically specific structure is a large (up to 35 μm), ellipsoid, homogeneous, cytoplasmic inclusion that is found in the cells of the stratum granulosum and the stratum corneum

Answer 73

molluscum contagiosum

Question 74

The pathogenesis of blister formation in impetigo is related to bacterial production of a toxin that specifically cleaves ____

Answer 74

Dmg1