Dermatopathology II-Fung

Question 1

Which components of the skin can neoplasms arise from?

Answer 1

epidermis: squamous or melanocytic
dermis
adnexal structures in the dermis: eccrine, apocrine, hair follicles

Question 2

What is seborrheic keratosis?

Answer 2

benign
neoplasm of unknown origin
no malignant potential
round flat lesions that is waxy.
uniform or darkly pigmented
velvety granular surface
**may still want a biopsy just to be sure

Question 3

What types of features might you see on histo of sebhorreic keratosis?

Answer 3

dome-shaped lesion
papillomatosis
hyperkeratosis
horn cysts

Question 4

What are horn cysts?

Answer 4

invagination of epidermis into the dermis

then keratin production!

Question 5

What is another name for a skin tag? What are they?

Answer 5

aka fibroepithelial polyps
no malignant potential
**stalk that connects to skin can become painful

Question 6

What are the features of skin tags on histo?

Answer 6

loose stroma surrounded by epidermis

Question 7

What are keloids? What is another name for them?

Answer 7

hypertrophic scars
abnormal dense deposition of collagen in the dermis
can come from ear piercings or acne
**African Americans have a higher propensity for these

Question 8

What is an epidermal inclusion cyst?

Answer 8

invagination of epidermis into dermis & then production of keratin! sometimes can rupture & cause inflammatory response as keratin spills out.

Question 9

What is actinic keratosis?

Answer 9

lesion that is due to sun damage
see tan brown or red colored lesion
skin feels like sandpaper
it is a dysplasia, but not a full carcinoma

Question 10

What does actinic keratosis look like on histo?

Answer 10

see some hyperkeratosis
dermis has solar elastois (UV breaks down collagen that is normally in the dermis)
dyskeratosis
see some abnormal nuclei-dark & big for keratinocytes

Question 11

What is squamous cell carcinoma in situ?

Answer 11

a more progressed form of actinic keratosis

but not invasive, contained w/i basement membrane

Question 12

What is Bowen’s disease?

Answer 12

this is squamous cell carcinoma in situ in the genital region

Question 13

What is basal cell carcinoma?

Answer 13

malignant epidermal tumor
pearly papules
some are pigmented
locally aggressive tumor
can erode into the bone if not taken care of!
**can sometimes be mistaken for melanoma

Question 14

What is the progression of melanocytic neoplasms: from benign–>malignant?

Answer 14

nevus
dysplastic nevus
melanoma
**most involved in Ras or Raf pathway

Question 15

What is a nevus?

Answer 15

common benign neoplasm that is acquired by activating mutations in the Ras signaling pathway
experiences morphological changes over time

Question 16

Describe the progression of a nevus.

Answer 16

junctional nevus: epidermis
compound nevus: epidermis & dermis
intradermal nevus: just dermis

Question 17

What is a dysplastic nevus?

Answer 17

a possible direct precursor to melanoma
most are stable & don’t progress
have the check point of p16
have acquired a mutation in the NRAS & BRAF genes already, tho

Question 18

What is melanoma?

Answer 18

deadly skin cancer
needs to be caught in early stages
can occur on skin or in oral, GI, or genital mucosa

Question 19

What prompt melanoma?

Answer 19

some of it is aut dom inherited
usu sporadic-UV radiation damage to DNA
**affects cell cycle control genes
activates pro-growth signaling pathways
activates telomerase

Question 20

What are the signs to look for that will tip you off to malignant melanoma?

Answer 20

A: asymmetry
B: borders
C: color
D: diameter
E: evolution ex: nevus matures & can form melanoma

Question 21

What are 2 important growth phases of melanoma?

Answer 21

lentigomalignant melanoma

superficial spreading melanoma

Question 22

What are the 2 types of growth of melanoma?

Answer 22

radial: grows w/i the epidermis **great if you can catch it here
vertical: worry about metastasis, goes thru the basement membrane & it is in the dermis

Question 23

What is Breslow Thickness & what is its significance?

Answer 23

depth of invasion of a melanoma into a dermis

lower the number-the better!

Question 24

What is Clarke’s level?

Answer 24

anatomical invasion level

Level 1-5

Question 25

What are adnexal neoplasms?

Answer 25

these are neoplasms of adnexal structures, including hair follicles, eccrine sweat glands, apocrine glands

Question 26

What is sebaceous hyperplasia?

Answer 26

adnexal neoplasm

too many sebaceous glands!

Question 27

What are pilar cysts?

Answer 27

these are adnexal neoplasms related to hair follicles

there are compact keratinocytes inside

Question 28

What is dermatofibroma? What is another name for it?

Answer 28

benign dermal neoplasm
seen in the dermis, strange collagen deposition, can infiltrate the subcutaneous tissue
aka benign fibrous histiocytoma

Question 29

T/F Dermatofibroma is the same thing as DFSP: dermatofibroma sarcoma protuberans.

Answer 29

False. They are different.
DFSP is malignant.
Dermatofibromas also don’t progress to DFSP.