Skin cancer

Question 1

What is the function of melanocytes?

Answer 1

Provide melanin pigment to neighbouring keratinocytes

Question 2

How often do melanocytes divide?

Answer 2

Infrequently (less than twice a year)

Question 3

What stimulate melanocyte proliferation + pigment production?

Answer 3

UV radiation-induced DNA damage to keratinocytes

Question 4

DNA damage induces what to p53?

Answer 4

Stabilisation of p53

Question 5

p53 induces the transcription of gene?

Answer 5

POMC (proopiomelanocortin)

-> melanin production

Question 6

Name the 4 types of cancer

Answer 6

Carcinoma = Begins in epithelium
Sarcoma = Begins in connective/supportive tissues (e.g. bone, fat, cartilage, muscles..)
Lymphoma + myeloma = Begin in cells of the immune system

Question 7

Name the 6 types of skin cancer

Answer 7

Keratinocyte cancers (98-99% of skin cancers)
Melanoma (1%)
Merkel cell carcinoma
Skin adnexal carcinomas
Kaposi's sarcoma
Cutaneous T-cell lymphoma

Question 8

What is the most deadly skin cancer?

Answer 8

Melanoma

Question 9

What is the most important risk factor for skin cancers?

Answer 9

UV radiation

Question 10

Which has the shorter wavelength - UVA or UVB?

Answer 10

UVB

Question 11

What effect does UVB have on the skin?

Answer 11

Skin burning

Question 12

What effect does UVA have on the skin?

Answer 12

Skin aging

Question 13

Which penetrates more deeply into skin - UVA or UVB?

Answer 13

UVA

Question 14

What is formed when DNA is damaged by UV light?

Answer 14

Dimers

Question 15

What are translesion polymerases?

Answer 15

Polymerases that can read through lesions so replication can carry on

Question 16

What is cSCC?

Answer 16

Cutaneous squamous cell carcinoma

Question 17

What are the 5 groups of people that are more susceptible to cSCC?

Answer 17

People who:

1) Have had significant cumulative UV exposure
2) Are more susceptible to sunburn
3) Are immunosuppressed
4) Have had organ transplant (due to anti-rejection drugs)
5) Have hereditary skin conditions

Question 18

What does cSCC look like?

Answer 18

Scaly/crusty
Sore/tender
Can bleed
Can appear as an ulcer

Question 19

What do typical cSCC have arising from the epidermis extending into the dermis?

Answer 19

Nests of squamous epithelial cells

Question 20

Which has multiple keratin pearls - well-differentiated cSCC or poorly-differentiated cSCC?

Answer 20

Well-differentiated cSCC

Question 21

Which has a poorer prognosis - well-differentiated cSCC or poorly-differentiated cSCC?

Answer 21

Poorly-differentiated cSCC