common skin cancers

Question 1

describe the outline of the skin layers

Answer 1

epidermis
dermis
subcutaneous layer

Question 2

what does the epidermis layer look like

Answer 2

the epidermis layer looks like:
keratinised cells 
granules cell layer 
prickle cell layers 
basal cell layer 
then the basal lamina 
in between we have langerhans cells and merkel cells for example

Question 3

where does proliferation of cells occur

Answer 3

in the basal lamina

Question 4

describe prickle cell layers

Answer 4

they have intercellular junctions and as they mature they develop keratin granules

Question 5

what do merkel cells do

Answer 5

proprioceptive functions

Question 6

where do squamous cells and basal cell carcinomas arise from

Answer 6

the epidermal layer

Question 7

where do melanomas arise from

Answer 7

melanocytes

Question 8

describe basal cell carcinomas

Answer 8

commonest malignant tumour
occur on sun exposed sites
metastasis is rare
can be locally aggressive- start in the dermis and move down into SC tissue

Question 9

what is the risk factor for BCC

Answer 9

UV light- esp in pale people
immunosuppressed
genetic predisposition eg gorlin syndrome or bazex drupe cristol syndrome

Question 10

describe gorlin syndrome

Answer 10

autosomal dominant
early development occurs of BCC in 20s-30s
1/100000 prevalence

Question 11

signs and symptoms of gorlin syndrome

Answer 11

palmer pits
odontogenic keratocytes
skeletal abnormality
mental retardation

Question 12

what can we see clinically in relation to gorlin syndrome

Answer 12

early lesions

ulceration centrally rodent ulcers-with pale edges

Question 13

describe the histology of BCC

Answer 13

the tumour is composed of islands of basaloid cells with peripheral palisade cells

Question 14

what do basaxoid cells show up as histologically

Answer 14

dark staining with minimal cytoplasm

Question 15

what do the low risk types of BCC look like histologically

Answer 15

superficial and nodular

Question 16

what do the high risk types of BCC look like histologically

Answer 16

infiltrative and micro nodular

Question 17

describe SCC

Answer 17

more aggressive than BCC

h

Question 18

what are some high risk sites for SCC

Answer 18

lip
ear
perineum
can occur in mucosal sites

Question 19

what is the metastasis rate in SCC

Answer 19

0.5-5% rate

Question 20

where does metastasis of SCC occur first

Answer 20

in the lymph nodes

Question 21

what are some risk factors for SCC

Answer 21

UV exposure high
immunosuppressed 
chronic ulcers 
radiation bands 
immunomodulatory drugs eg BRAF inhibitors

Question 22

what did percivall pott describe

Answer 22

that due to hydrocarbon exposure a lot of chimes sweeps develop SCC

Question 23

what can SCC look like clinically

Answer 23

scaley

nodular and ulcerated

Question 24

what can we see microscopically from SCC

Answer 24

arise from keratinocytes
try to replicate what normal cells look like
spinous processes between cells
invade BV and nerves

Question 25

why do we see actinic keratosis

Answer 25

due to chronic UV exposure

Question 26

what does acinitic keratosis look like clinically

Answer 26

scaley lesion with erythematous base | rarely progresses to an invasive disease

Question 27

what does acinitic keratosis look like histologically

Answer 27

abnormal nuclei which are big

Question 28

where do melanocytes derive from

Answer 28

the neural crest

Question 29

what is the function of melanocytes

Answer 29

to from melanin which is transferred to epidermal cells to protect the nucleus from radiation

Question 30

what are benign melanocytic tumours called

Answer 30

naevi

Question 31

what are malignant melanocytic tumours called

Answer 31

melanomas

Question 32

describe naevi

Answer 32

local benign collections of melanocytes

Question 33

where are naevi found

Answer 33

in the superficial dermis and move down the layers

Question 34

what do naevi look like

Answer 34

uniform and well circumscribed

Question 35

what are the different types of naevi

Answer 35

superficial | deep

Question 36

what do deep naevi look like

Answer 36

deep blue colour

Question 37

describer atypical mole syndrome

Answer 37

irregular shaping of moles | usually with families with an increased melanoma risk

Question 38

why might people have atypical mole syndrome

Answer 38

due to mutations in the CDKN2A

Question 39

what does mutations in the CDKN2A gene lead to

Answer 39

atypical mole syndrome

Question 40

what is a risk factor for atypical mole syndrome

Answer 40

UV exposure pale skin family history of melanomas

Question 41

describe what a naevi looks like

Answer 41

``` symmetrical even borders uniform colour less than 6mm in diameter lesion hasn't changed over time ```

Question 42

what does a melanoma look like

Answer 42

``` asymmetrical uneven borders different colours greater than 6mm in diameter lesion starts to change over time ```

Question 43

what is the most common melanoma in UK

Answer 43

superficial spreading melanoma

Question 44

what does the early stage of a superficial spreading melanoma look like

Answer 44

a flat macule

Question 45

what does a late stage of a superficial spreading melanoma look lik

Answer 45

blue/black nodule

Question 46

what does the late stage of the superficial spreading melanoma look like microscopically

Answer 46

proliferation fo the atypical melanocytes at the dermal epidermal junction which invades the epidermis and then can spread to the BV and nerves

Question 47

what are some genetic reasons for superficial spreading melanoma

Answer 47

B-RAF proto oncogene mutations

Question 48

describe nodular melanomas

Answer 48

starts off as a pigmented nodule which can be ulcerated

Question 49

where are nodular melanomas found

Answer 49

on areas with intermittent sun exposure

Question 50

what do we see in nodular melanomas microscopically

Answer 50

invasive atypical melanocytes invading the dermis

Question 51

describe lentigo maligna

Answer 51

found on elderly pts on sun exposed sites flat pigmented patch

Question 52

how is lentigo maligna formed

Answer 52

by disc adhesive single cells and then they go into the dermis

Question 53

what do we see microscopically in lentigo melanoma

Answer 53

proliferation of abnormal melanocytes along the basal layer

Question 54

which mutation is commonly seen in letigo maligna

Answer 54

KIT mutations

Question 55

where are kit mutations commonly seen

Answer 55

lentigo maligna | acral lentiginous melanoma

Question 56

where can acral lentiginous melanoma be seen

Answer 56

on palms and soles | or sublingual

Question 57

which group has a predominance to acral lentiginous melanoma

Answer 57

afro carribeans

Question 58

what does the microscopy seen in acral lentiginous melanoma show

Answer 58

proliferation of abnormal melanocytes along the basal layer | but no marked sun damage

Question 59

where do mucosal melanomas occur

Answer 59

``` oral nasal GU GI tract ```

Question 60

what do we microscopically see in mucous melanomas

Answer 60

early lengitinous growth along the border between epithelium and CT

Question 61

which mutations do we see in mucosal melanomas

Answer 61

KIT | GNAQ mutations

Question 62

what does mucosal melanomas mimic

Answer 62

amalgam pigments

Question 63

what is prognosis of cancers based on

Answer 63

breslow thickness

Question 64

where is prognosis works

Answer 64

in the BANS area | if ulcerated

Question 65

what treatment can we use

Answer 65

surgery removal when small or if too late immunotherapy-

Question 66

what does the breslow thickness look at

Answer 66

the measure between the granular layer to the base of the epidermis