Skin Tumours

Question 1

Why do you get lots of primary cancers in the skin?

Answer 1

Because of a large background field of mutations accumulating.

Question 2

What is an oncogene?

Answer 2

A gene that drives cell division.

Question 3

Give three examples of oncogenes.

Answer 3

Ras, Raf, Growth factor receptors

Question 4

What is a tumour suppressor gene?

Answer 4

A gene that inhibits cell growth.

Question 5

Give an example of a tumour suppressor gene.

Answer 5

P53, Rb

Question 6

What are the two broad categories of skin cancer?

Answer 6

Pigmented and Non-pigmented cancers

Question 7

Give 5 risk factors for skin cancer development.

Answer 7

UV exposure 
Age
Immunosuppression
Genetics
Chemical exposure

Question 8

What are the two types of melanin produced?

Answer 8

Eumelanin- Brown/Black

Pheomelanin- Red/Yellow

Question 9

What Fitzpatric group only produce pheomelanin?

Answer 9

1

Question 10

What are the two categories of NMSC?

Answer 10

Basal Cell Carcinoma

Squamous Cell Carcinoma

Question 11

What two categories of skin cancer are associated with intermittent burning?

Answer 11

BCC and MM

Question 12

What skin cancer is associated with chronic sun exposure?

Answer 12

SCC

Question 13

What cancers can chemical exposure increase?

Answer 13

BCC and SCC

Question 14

Which autoimmune conditions can increase MM?

Answer 14

UC and Crohn’s.

Question 15

What is the wavelength of UVB and how does it cause damage?

Answer 15

290-320nm and directly damages DNA

Question 16

What is the wavelength of UVA and how does it cause damage?

Answer 16

320-400nm and causes oxidative stress.

Question 17

WHat does UV radiation do the the immune system?

Answer 17

Immunosuppression.

Question 18

What does UVB damage to the DNA look like?

Answer 18

Covalent bonding between adjacent pyrimidines causing a kink in the chain. Two forms: CPD and 6-4.

Question 19

What type of UVB damage is most common and which is most damaging?

Answer 19

CPD most common

6-4 most damaging.

Question 20

How does UVA cause DNA damage?

Answer 20

Oxidises bases therefore preventing repair.

Question 21

What mutation is BCC strongly associated with?

Answer 21

PTCH1

Question 22

WHat mutation is MM strongly associated with?

Answer 22

B-Raf

Question 23

What drugs are given for B-Raf mutations?

Answer 23

Vemurafenib and Dabrafenib

Question 24

What cells do MM arise from?

Answer 24

Melanocytes

Question 25

What cells do NMSC arise from?

Answer 25

Keratinocytes

Question 26

What general term is used to describe a MM?

Answer 26

Ugly duckling

Question 27

How is the severity of a MM measured?

Answer 27

Breslow Thickness

Question 28

Where is the Breslow thickness measured from and to?

Answer 28

From the granular layer to the deepest point of MM.

Question 29

What are the categories in the Breslow thickness and what are their prognosis?

Answer 29

<1mm- Good. 95% chance of surviving. 1-4mm- Okay >4mm- Bad. 5% chance of surviving.

Question 30

What is the ABCDE of MM?

Answer 30

``` Asymmetry Border- Ill Defined Colour- Mixed Diameter- If over 5mm the problematic Evolution- Evolves quickly ```

Question 31

What would be a differential diagnosis for MM?

Answer 31

Pyogenic Granuloma

Question 32

What form do BCC generally take?

Answer 32

Slow growing lumps or non-healing ulcers. Rodent ulcer Pearly with visible blood vessels Poorly defined Painless Can be pigmented Generally seen in younger patients- 40YO Do not metastasize but can get multiple primaries.

Question 33

How do you treat BCC?

Answer 33

Skin surgery

Question 34

What form do SCC generally take?

Answer 34

Warty or crusty lump or ulcer- Hyperkeratotic Fast growing and can be painful or bleed. Generally well defined but can be ill defined. Can metastasize.

Question 35

What is a precursor lesion to SCC called?

Answer 35

Actinic keratoses and Bowen's disease.

Question 36

What word is often used to describe SCC?

Answer 36

Cutaneous horn

Question 37

What do actinic keratoses look like?

Answer 37

Flat and red then progress to scale and hyperkeratosis.

Question 38

What do Bowen's disease look like?

Answer 38

Erythematous plaques generally on lower leg. | Irregular border with no dermal invasion

Question 39

What fraction of SPF stated do you actually get?

Answer 39

1/3

Question 40

What is another term for each skin cancer category?

Answer 40

Malignant melanoma and Non-Melanoma Skin Cancer

Question 41

What are the two types of lesion in pigmented skin cancers?

Answer 41

MM and Melanocytic naevi.

Question 42

What is an actinic lentigines?

Answer 42

Solar lentigines or liver spots due to UV exposure. | Due to increase melanin and melanocytes.

Question 43

What percentage of MN are congenital?

Answer 43

1-2%

Question 44

What are the three size of MN?

Answer 44

Small <2cm Med 2-20cm Giant >20cm

Question 45

What are the 4 types of MN?

Answer 45

Normal/usual- All have them Dysplastic Spitz Blue

Question 46

Describe dysplastic MN.

Answer 46

Asymmetrical border, pigmentation variation and >6mm | Can progress to MM

Question 47

Describe blue MN

Answer 47

Dermal in origin and can be found in prostate or oesophagus.

Question 48

Describe Spitz MN.

Answer 48

Mimics MM but is benign | Occurs in <20YO

Question 49

WHat are the 4 types of MM and where are they found?

Answer 49

Superficial spreading- Trunk and limbs Acral/Mucosal lentiginous- Acral (nail) and Mucosal Surfaces Lentigo maligna- Sun damaged skin. Can progress to Lentigo maligna melanoma. Nodular- Often on trunk

Question 50

How are pigmented tumours graded?

Answer 50

``` pTis- In situ pT1- <1mm pT2- 1-2mm pT3- 2-4mm pT4- >4mm Not ulcerated gets a Ulcerated gets b ```

Question 51

Where does MM often spread to?

Answer 51

``` Start with lymph then: Liver Heart Skin Brain GI Lungs ```

Question 52

How do you treat MM?

Answer 52

Excise it Do a node biopsy Chemotherapy Immunotherapy