Y5 - Benign skin lesions (incl. dermatofibroma, seborrhoeic keratoses)

Question 1

def of dermatofibroma

Answer 1

benign skin growth

Question 2

dermatofibroma is AKA

Answer 2

benign fibrous histiocytomas

Question 3

signs and symptoms of BFH

Answer 3

hard solitary slow-growing papules (rounded bumps)

usually nothing, but sometimes itching and tenderness

Question 4

what colour are BFH

Answer 4

tanned/brownish colour

Question 5

what sign is BFH associated with

Answer 5

dimple sign

Question 6

what is dimple sign

Answer 6

applying lateral pressure causes a central depression of the dermatofibroma

Question 7

where are dermatofibromas most commonly found

Answer 7

on the legs and arms

Question 8

epi of BFH

Answer 8

women>men

young adults

Question 9

aetiology of BFH

Answer 9

possibly related to previous injuries (insect bites or thorn pricks)
causing disordered collagen to be laid down by fibroblasts

Question 10

what is the positive buttonhold sign

Answer 10

central dimpling in the center of BFH

Question 11

what are dermatofibromas

Answer 11

positive for stromelysin-3, and factor XIIIa

Question 12

management for BFH

Answer 12

usually none

Question 13

prognosis of BFH

Answer 13

excellent

some may suffer from pain or itching

Question 14

physical examination of a BFH

Answer 14

solitary <1cm nodule

Question 15

def of SK

Answer 15

a common, multiple, benign skin tumour

Question 16

where is SK commonly found

Answer 16

on the torso

Question 17

epi of SK

Answer 17

middle age

vvv common

Question 18

what do SK look like

Answer 18

circumscribed grey/brown/black plaques with a stuck on appearance

Question 19

aetiology of SK

Answer 19

clonal expansion of mutated epidermal keratinocytes by unknown cause
possibly associated with chronic UV damage

Question 20

what mutations are involved in SK

Answer 20

FGFR3 mutations

Question 21

signs and symptoms of SK

Answer 21

• ‘stuck on’ lesions
• on face or torso
• yellow-dark brown
• slightly raised lesion with a wart like texture

Question 22

RFs of SK

Answer 22

older
white
FHx

Question 23

investigations of SK

Answer 23

dermoscopy
-milia-like cysts and comedo-like openings
biopsy and histopathological examination
-sharply defined exophytic lesions

Question 24

management of SK

Answer 24

for itchy lesions
-corticosteroids (betamethasone)
for raised SK
-curretage or cautery
for flat SK
-cryotherapy

Question 25

which is used more curretage or cautery

Answer 25

curretage as leaves no scars

Question 26

what is used for cryotherapy

Answer 26

liquid nitrogen

Question 27

complications for SK

Answer 27

irritation and itching

Question 28

prognosis

Answer 28

good

Question 29

what is ammonium lactate useful for

Answer 29

reducing height of SK