Derm Path I

Question 1

What is the role of the stratum basale?

Answer 1

Keratinocyte stem cells

Question 2

What is the role of the stratum spinosum?

Answer 2

Production of keratin

Question 3

What is the role of hte stratum granulosum?

Answer 3

Processes keratin to make it soft

Nails don’t have stratum granulosum –> why it’s not soft

Question 4

What is the role of the stratum lucidem and where in the body is it found?

Answer 4

Protective against shear force

Found in thick skin- in the palms and soles of feet

Question 5

What is the role of the stratum corneum?

Answer 5

Adds strength- primarily dead cells- deals with water balance as well

Question 6

What do Merkel cells look like under a microscope?

Answer 6

Nothing - you can’t see them!

Question 7

What cells are disordered in ichthyosis?

Answer 7

Keratinocytes

Question 8

What is the path of ichthyosis?

Answer 8

Defective desquamation leads to build up of compacted scale

Question 9

Which enzyme is deficient in x-linked ichthyosis?

Answer 9

Steroid sulfatase, responsible for “breaking down the concrete between the bricks so the bricks can slough off”

Question 10

What is orthokeratosis?

Answer 10

Fish-like scales - seen in ichthyosis

Question 11

“barnacles of age” are the dominant feature of what derm condition?

Answer 11

Seborrheic keratosis

Question 12

What is the clinical morphology of seborrheic keratosis?

Answer 12

“Stuck on” verrucous waxy appearing brown papules or plaques anywhere on the skin except the palms and soles

Question 13

What is “papillomatosis”

Answer 13

The Bart Simpson sign-

Question 14

What is the major difference between seborrheic keratosis and melanoma?

Answer 14

Lack of atypia in sebhorreic

Flat base “string sign” present in sebhorreic – line in which the hyperplasia does not invade into the dermis

Question 15

Which disease process is described by poorly defined, hyperpigmented verrucous plaques with a velvety scale commonly found in the creases of the axilla and neck?

Answer 15

Acanthosis nigricans

Question 16

Which layer of the skin undergoes hyperpigmentation in acanthosis nigricans?

Answer 16

basal layer

Question 17

What two histologic findings are found both acanthosis nigricans and seborrheic nigricans?

Answer 17

Hyperkeratosis and papillomatosis

Question 18

Which two histologic findings differentiate seborrheic keratosis from acanthosis nigricans?

Answer 18

Shoe-string sign

Pseudo horn cysts

Question 19

What is the Leser-Trelat sign?

Answer 19

Eruption of MANY many seborrheic keratosis spots

Indicative of a paraneoplastic syndrome (predominantly GI)

Question 20

Differentiate the age of onset of benign type vs malignant type of acanthosis nigricans

Answer 20

Benign: childhood (usually caused by obesity/endocrine or hereditary)

Malignant: middle age and up

Question 21

What is an acrochordon?

Answer 21

Fibroepithelial polyp/skin tag

Question 22

How would you describe a skin tag?

Answer 22

Flesh colored pedunculated papule

Question 23

What is the core of a acrochordon?

Answer 23

Fibrovascular core

Question 24

What is the name for a common scaly erythematous patch/macule located on sun-damaged skin?

Answer 24

Actinic Keratosis

Question 25

Actinic keratosis is a precursor of which neoplasm?

Answer 25

Squamous cell carcinoma

Question 26

What is the treatment for actinic keratosis?

Answer 26

cryotherapy or topical chemotherapeutics to prevent progression to squamous cell carcinoma They are all treated, although not all will become SCC

Question 27

What is the flag sign?

Answer 27

Parakeratosis alternating with orthoparakeratosis Parakeratosis = retention of nuclei

Question 28

What is Bowen's disease?

Answer 28

Squamous cell carcinoma in situ Histo: atypia at all levels of the epidermis Clinical: irregular scaly erythematous plaque like lesion

Question 29

What is bowenoid papulosis?

Answer 29

Squamous cell carcinoma in situ Histo: similar to Bowen's- atypia at all levels of the epidermis Clinically: HPV induced, located on the genitals, frequently multiple papules, may spontaneously regress or progress

Question 30

Why do you not see the flag sign in bowen's disease?

Answer 30

Because the atypia involves the hair follicle

Question 31

What is the second most common skin tumor?

Answer 31

Squamous Cell Carcinoma

Question 32

Who is at risk for developing squamous cell carcinoma?

Answer 32

People with lots of sun exposure, older individuals and males

Question 33

What mutations are commonly associated with squamous cell carcinoma?

Answer 33

TP53

Question 34

What is the risk of metastasis with squamous cell carcinoma?

Answer 34

Less than 5% metastasize

Question 35

What is the invasion pattern of squamous cell carcinoma?

Answer 35

They follow nerves- but they don't enter blood vessels and metastasize

Question 36

Where is the keratinocyte atypia in actinic keratosis?

Answer 36

Basal cell layer

Question 37

Where is the keratinocyte atypia in SSC in situ?

Answer 37

full thickness

Question 38

Does actinic keratosis involve the hair follicle?

Answer 38

No - this is why you get the flag sign

Question 39

Does SSC in situ involve the hair follicle?

Answer 39

yes- this is why you don't see the flag sign

Question 40

Is basal cell carcinoma invasive?

Answer 40

Yes- it is the most common invasive cancer in humans

Question 41

What is a gene mutation associated with 30% of basal cell carcinomas?

Answer 41

PTCH

Question 42

Describe Nevoid Basal Cell Carcinoma Syndrome/Gorlin syndrome

Answer 42

AD Multiple BCC before age 20 Accompanied by medulloblastomas, ovarian fibromas, odantogenic keratocysts

Question 43

What is the gene mutated in Nevoid Basal Cell carcinoma/Gorlin syndrome?

Answer 43

PTCH on chromosome 9q22.3 Two hit hypothesis

Question 44

What is the clinical morphology of basal cell carcinoma?

Answer 44

Pearly pink papule with underlying telangectasia

Question 45

"Peripheral palisading" architecture is typical of what type of neoplasm?

Answer 45

Basal cell carcinoma

Question 46

"Clefting" between the tumor and the stroma is indicative of what cancer?

Answer 46

basal cell carcinoma

Question 47

What is the cause of vitiligo

Answer 47

Autoimmune destruction of MELANOCYTES

Question 48

What do we see on histology for vitiligo?

Answer 48

Loss of melanocytes

Question 49

What is the cause of albinism?

Answer 49

Decreased tyrosinase activity, or defective transport of melanin

Question 50

What is melasma?

Answer 50

HYPERpigmentation of the skin seen in pregnancy or OBC use

Question 51

Where does melanin deposit in melasma?

Answer 51

Melanin deposits in the dermis