dermatology

Question 1

what layer of the skin is affected by basal cell carcinoma?

Answer 1

the basal layer of the epidermis

Question 2

what is the prognosis of BCC and why?

Answer 2

good because they develop slowly and rarely metastasise

Question 3

what are the 3 main types of basal cell carcinoma?

Answer 3

nodular BCC
superficial BCC
morpheaform BCC

Question 4

what is the most common type of BCC?

Answer 4

nodular BCC

Question 5

where does nodular BCC usually present?

Answer 5

on the face

Question 6

what is the clinical appearance of nodular BCC?

Answer 6

pearly shiny papule or nodules w/ small telangiectasis and rolled edges and someones a depressed centre

Question 7

what is the second most common type of BCC?

Answer 7

superficial BCC

Question 8

how does superficial BCC usually present?

Answer 8

as a plaque or patch of well defined scaly pink skin

Question 9

where do superficial BCCs usually present?

Answer 9

on the trunk or extremities

Question 10

what is the least common type of BCC?

Answer 10

morpheaform BCC

Question 11

how does morpheaform BCC usually present?

Answer 11

as a poorly defined pale scar or indurated plaque

Question 12

which type of BCC has the worst prognosis and why?

Answer 12

morpheaform BCC because it can subclinically destroy surrounding tissue

Question 13

what is the main treatment goal of BCC?

Answer 13

complete removal

Question 14

other than complete surgical resection what are the other management options for BCC?

Answer 14

topical 5 fluoro-uracil
cryotherapy
photodynamic therapy

Question 15

where does squamous cell carcinoma occur?

Answer 15

in the squamous keratinocytes in the epidermis (the outermost layer of the skin)

Question 16

where do SCCs most commonly occur?

Answer 16

in sun exposed areas such as the lips, back of hands, upper part of face or scalp

Question 17

what are the 3 characteristic features of SCC?

Answer 17

bleeding
itching
crusting

Question 18

what are the 2 pre cancerous lesions that can progress to SCC?

Answer 18

Bowens disease
actinic keratosis

Question 19

what is Bowens disease?

Answer 19

SCC in situ - the cancerous cells are confined to the epidermis

Question 20

what is actinic keratosis?

Answer 20

a pre cancerous scaly lesion

Question 21

what is the first line management for Bowens disease?

Answer 21

restrictive therapies:
- cryotherapy
- topical 5 fluoro-uracil

Question 22

what is the first line management for invasive SCC?

Answer 22

surgical excision w/ minimum of 4mm margins

Question 23

what is the treatment of choice of SCC in cosmetically sensitive areas?

Answer 23

Mohs surgery

Question 24

what causes melanoma?

Answer 24

uncontrolled proliferation of melanocytic stem cells

Question 25

what are the 3 growth phases of melanoma?

Answer 25

in situ: the tumour is confined to the epidermis invasive: the tumour has spread to the dermis metastatic: the tumour has spread to other tissues

Question 26

what are the 4 subtypes of melanoma?

Answer 26

superficial spreading melanoma nodular melanoma lentigo maligna melanoma aural lentiginous melanoma

Question 27

what is the most common subtype of melanoma?

Answer 27

superficial spreading melanoma

Question 28

how does superficial spreading melanoma progress?

Answer 28

initially grows horizontally (radial growth phase) and this presents as a flat irregular pigmented lesion that slowly enlarges as invasion continues, growth may become vertical

Question 29

what is the most aggressive subtype of melanoma?

Answer 29

nodular melanoma

Question 30

how does nodular melanoma progress?

Answer 30

malignant cells invade vertically, presenting as a nodule that grows rapidly (weeks to months) often bleeds or ulcerates

Question 31

what is lentigo maligna?

Answer 31

a precursor lesion to lentigo maligna melanoma that is directly related to sun damage

Question 32

how does lentigo maligna present?

Answer 32

as a patch of discoloured skin that grows slowly and becomes more atypical

Question 33

where does acral lentigenous melanoma occur?

Answer 33

on the palms, soles or under the nails

Question 34

how does acral lentigenous melanoma present?

Answer 34

as a flat pigmented lesion that slowly enlarges

Question 35

what is breslows thickness?

Answer 35

a measure of the thickness of invasive melanoma in mm from the granular layer to the deepest tumour layer

Question 36

at what breslows thickness is a sentinel node biopsy needed?

Answer 36

>0.8mm

Question 37

what is the management of stage 0 melanoma (in situ)?

Answer 37

wide local excision w/ at least 0.5cm margin

Question 38

what is the management of stage 1 melanoma (melanoma <2mm thickness)?

Answer 38

wide local excision w/ at least 1cm margin

Question 39

what is the management of stage 2 melanoma (melanoma >2mm thickness or >1mm thickness w/ ulceration)?

Answer 39

wide local excision w/ at least 2cm margins

Question 40

what is the management of stage 3 melanoma (melanoma spread to involve local lymph nodes)?

Answer 40

wide local excision w/ lymphaedenectomy