Malignant and pre malignant skin tumours

Question 1

What is the presentaiton of basal cell carcinoma?

Answer 1

This is a rodent ulcer as it erodes away at supprounding tissue without spreading
Presents as a pearly nodule with rolled telangietactic edge with or without central ulcer

Question 2

What is the treatment of basal cell carcinoma?

Answer 2

Excision is often the treatment of choice with 4mm margin, can use cryotherapy for certain lesions
Topical fluorouracil can be used for low risk superficial lesions

Question 3

What is the presentation and treatment of actinic keratoses?

Answer 3

Pre-malignant scaly crusts on sun exposed skin
Treatment:
-Conservative - avoid further sun exposure - no treatment for mild
-Diclofenac gel - twice daily for 60-90 days
-Fluorouracil - 5% cream daily for 6 weeks - causes necrosis of AK
-Cryotherapy - effective in up to 75%
-Photodynamic therapy - effective in up to 91%
-Surcal excision - if unresponsive to other treatments or SCC suspected

Question 4

What is the presentation and treatment of Bowen’s disease?

Answer 4

It is an SCC in situ
A well defined slow-enlarging red-scaly plaque with a flat edge (asymptomatic)
3-5% pregress to squamous cell cancer
Treatment options are similar to AK

Question 5

What is the presentation and treatment of SCC?

Answer 5

This is an ulcerated or crusted firm irregular lesion. It is often indurated (raised base)
Locally invasive and may metastasise so always treat with local complete excision with 4mm margin if under 20mm and 6mm if over 20mm

Question 6

What is the difference between a sebhorrheic keratosis and an actinic keratosis?

Answer 6

Sebhorrheic are benign and appear like greasy brown warty lesions, they are not usually on sun exposed sites, occur with age
Actinic kerastoses are in sun expsored sites and are crumbly yellow-white scaly crusts, they are pre malignant

Question 7

Where do most melanomas arrise?

Answer 7

In sites that did not originally have moles

Question 8

What are the risk factors for melanomas?

Answer 8

UV expore
Sunburn
Fair complexion
Lots of naevi
Fmaily history
Previous melanoma
Old age

Question 9

What are the signs of melanoma?

Answer 9

A-E criteria
Asymmetry in the outline of the lesion
Border irregular or blurring
Colour variation - different shades
Diameter - greater than 6mm
Evolution - changing moles
Funny looking

Question 10

What is the management for suspected melanoma?

Answer 10

Refer urgently 2 week wait
Excision biopsy with 2mm margin
Then breslow thickness is determined
Then remove the scar with sufficient margins

Question 11

How is mmetastatic melanoma treated?

Answer 11

Treated with use of interferon alpha if it is node positive

Later stage disease is not curable and will require palliation

Question 12

What is the natural progression of naevi?

Answer 12

As an individual gets other melanocytes can migrate to the skin surface causing moles to become domed. In older age they will begin to lose their pigmentation and will eventually disappear

Question 13

What is a halo naevus and is it a bad sign?

Answer 13

This is the result of T cell attack of the melanocytes resulting in a patch of hypopigmented skin surrounding the naevus. This is normal and benigin in teenagers but could indicate melanoma elsewhere in middle age

Question 14

What are the different types of melanoma?

Answer 14

Superficial spreading melanoma - 70%
Nodular melanoma - 15% - most aggressive
Acral lentiginous melanoma - 10%
Lentigo maligna melanoma - 5%

Question 15

What are the characteristics of superficial spreading melanoma?

Answer 15

This is the most common form of melanoma - it spreads radially slowly before vertical invasian

Question 16

What are the characteristics of nodular melanoma?

Answer 16

This is the most aggressive form and lesions grow rapidly, invade deeply and metastasise early. Often darkly pigmented

Question 17

What are the characteristics of Acral lentiginous melanomas?

Answer 17

These occur on the palms, soles and subungal areas. Most common melanoma in black and asian skin. Refer urgently all new pigmented line in a nail

Question 18

How does breslow thickness affect prognosis?

Answer 18

5 year survival
< 1 mm	95-100%
1 - 2 mm	80-96%
2.1 - 4 mm	60-75%
> 4 mm	50%

Question 19

What are the skin types?

Answer 19

I Pale white skin, blue/green eyes, blond/red hair Always burns, does not tan
II Fair skin, blue eyes Burns easily, tans poorly
III Darker white skin Tans after initial burn
IV Light brown skin Burns minimally, tans easily
V Brown skin
VI Dark brown skin