Skin cancer

Question 1

From what cells in the skin do basal cell carcinomas arise?

Answer 1

Keratinocytes in the basal layer of skin

Question 2

From what cells in the skin do squamous cell carcinomas arise?

Answer 2

Keratinocytes in the suprabasal layers

Question 3

How do basal cell carcinomas usually present?

Answer 3

A translucent, slow-growing lump or a non-healing ulcer

Painless

Question 4

Why is delay in treatment of basal cell carcinoma less important than in other cancers?

Answer 4

Although they invade locally, they don’t spread more widely

Question 5

How do squamous cell carcinomas tend to present?

Answer 5

A warty or crusted growth or a non-healing ulcer

May be painful

Hyperkeratotic

Question 6

Which tends to grow faster: basal cell or squamous cell carcinoma?

Answer 6

Squamous cell

Question 7

What is the most common cancer in 15-24 year olds?

Answer 7

Malignant melanoma

Question 8

What is used to determine prognosis from malignant melanoma?

Answer 8

Breslow thickness

Question 9

What is the prognosis of a malignant melanoma with a Breslow thickness >4mm?

Answer 9

5 year survival rate 50%

Question 10

What does ABCDE stand for in terms of assessing skin lesions?

Answer 10

Assymetry

Border

Colour

Diameter

Evolution

Question 11

What is the name given to a lesion with central ulceration and what is the diagnosis most likely to be?

Answer 11

Rodent ulcer

Basal cell carcinoma

Question 12

Which skin cancer tends to have visible blood vessels in it’s lesions?

Answer 12

Basal cell carcinoma

Question 13

What are precursor lesions to SCC?

Answer 13

Actinic keratoses

Bowen’s disease (carcinoma-in-situ)

Question 14

What are the predisposing factors to development of skin cancer?

Answer 14

UV light from sunlight and sunbeds

Skin type

Moles

Family history/genetics

Some drugs

Other cancer

Question 15

What kind of UV light exposure predisposes to development of BCC?

Answer 15

Intermittent exposure

Question 16

What kind of UV light exposure predisposes to development of SCC?

Answer 16

Chronic exposure

Question 17

What kind of UV light exposure predisposes to development of malignant melanoma?

Answer 17

Intermittent exposure

Question 18

Which type of UV damage is reflected by sunburn and solar lentigo?

Answer 18

UVB damage

Question 19

What type of damage occurs to skin with UVA exposure?

Answer 19

Solar ageing is attributed to the deeper penetration and solar elastosis of UVA

Question 20

What is sunburn?

Answer 20

A protective mechanism whereby badly UV-damaged keratinocytes undergo apoptosis or programmed cell death

Question 21

What are some examples of phototoxic drugs?

Answer 21

Voriconazole

Thiazide diuretics

Anti-TNF

NSAIDs

BRAF inhibitors

Question 22

What are actinic/solar lentiges?

Answer 22

‘Age’ or ‘liver’ spots associated with UV exposure

Question 23

Where are actinic lentiges found?

Answer 23

Face, forearms and dorsal hands

Question 24

What is the risk of developing melanoma with a large congenital melanocytic naevi?

Answer 24

10-15%

Question 25

What are the characteristics of a dysplastic naevi?

Answer 25

Generally \>6mm diameter Variegated pigment Border asymmetry

Question 26

What is this lesion?

Answer 26

Halo naevus

Question 27

What are halo naevus and what are they associated with?

Answer 27

A mole surrounded by an area of depigmentation Associated with vitiligo

Question 28

What is seen on biopsy of halo naevus?

Answer 28

They show inflammatory regression and are overrun by lymphocytes

Question 29

What is this lesion and what does it consist of?

Answer 29

Blue naevus - collection of dendritic rich spindle cells in the dermis that may mimic melanoma

Question 30

What is this lesion?

Answer 30

Spitz naevus

Question 31

What is a spitz naevus?

Answer 31

'benign juvenile melanoma' Consist of large spindle and/or epithelioid cells and may closely mimic melanoma, however most are entirely benign

Question 32

In which gender are malignant melanomas most common?

Answer 32

Females 2:1

Question 33

What features might raise suspicion that a lesion is a malignant melanoma?

Answer 33

New lesion develops in adulthood Satellite lesions Bleeding Change in shape Ulceration Irregular pigmentation

Question 34

What is the most common type of malignant melanoma?

Answer 34

Superficial spreading melanoma

Question 35

Where do acral lentiginous melanomas arise?

Answer 35

Palms Soles Beneath nails

Question 36

Which type of melanoma arises on sundamaged skin of the face, neck and scalp?

Answer 36

Lentigo maligna

Question 37

What is 'VGP' in relation to malignant melanoma?

Answer 37

Melanoma cells invade the dermis forming an expansile mass with mitoses

Question 38

Which type of melanoma are VGP only?

Answer 38

Nodular

Question 39

What is RGP in relation to malignant melanoma?

Answer 39

Grows as macules when either entirely in-situ or with dermal microinvasion

Question 40

What is the definition of Breslow thickness?

Answer 40

Depth of the deepest part of tumour from granular layer

Question 41

What are poor prognostic indicators in malignant melanoma?

Answer 41

Increasing Breslow thickness Satellite lesion formation Ulceration High mitotic rate Lymphovascular invasion Sentinel lymph node involvement

Question 42

How does malignant melanoma spread?

Answer 42

Local dermal lymph nodes Regional lymph nodes Blood spread

Question 43

What are satellite nodules with malignant melanoma?

Answer 43

MM spreading to dermal lymph nodes

Question 44

Where do metastates from malignant melanoma spread?

Answer 44

Skin Heart Lungs GI tract Brain Liver

Question 45

What size of margin should be left when doing an excision of a malignant melanoma in situ?

Answer 45

5mm

Question 46

What size of margin should be left when removing an invasive malignant melanoma \<1mm thick?

Answer 46

1 cm

Question 47

What size of margin should be left in excision of an invasive malignant melanoma \>1mm thick?

Answer 47

2cm

Question 48

When should a sentinel node biospy be performed with malignant melanoma?

Answer 48

\>1mm thick or thinner with mitoses

Question 49

What are these lesions?

Answer 49

Seborrhoeic keratosis

Question 50

What are some of the precursors for squamous cell carcinoma and where are they commonly found?

Answer 50

Bowen’s disease: legs Actinic keratosis: head/neck Viral lesions: anogenital skin

Question 51

What are the characteristics of Bowen's disease?

Answer 51

Normally on lower leg Scaly patch/plaque Irregular border No dermal invasion More common in females