[11] Actinic Keratosis

Question 1

What is actinic keratosis?

Answer 1

A pre-cancerous area of thick, scaly, or crusty skin

Question 2

What is the underlying cause of actinic keratosis?

Answer 2

UV-induced DNA damage within the skin

Question 3

How does sunlight cause DNA damage?

Answer 3

Photo-aging leads to an accumulation of oncogenic changes

Question 4

What is the result of the oncogenic changes to skin cell DNA in actinic keratosis?

Answer 4

Proliferation of mutated keratinocytes that can manifest as actinic keratosis or other neoplastic growths

Question 5

What are the three paths that actinic keratosis can take?

Answer 5

• Remain stable
• Progress to Bowen’s disease
• Progress to SCC

Question 6

What are the risk factors for actinic keratosis?

Answer 6

• Fair skin
• Immunosuppression
• HPV
• Balding

Question 7

What are the signs of a person who would be considered fair skinned?

Answer 7

• Freckling
• Light hair and eye colour
• Propensity to sunburn
• Inability to tan

Question 8

What is the typical morphology of actinic keratosis?

Answer 8

White, scaly plaque of variable thickness with surrounding redness

Question 9

What is the typical size of actinic keratosis?

Answer 9

2-6mm (can be several cm)

Question 10

Are actinic keratosis lesions usually symptomatic?

Answer 10

No

Question 11

What are the uncommon presenting symptoms of an actinic keratosis lesion?

Answer 11

• Tenderness
• Itching
• Bleeding
• Stinging or burning sensation

Question 12

What parts of the body to actinic keratosis develop on?

Answer 12

Those exposed to sunlight

Question 13

What parts of the body are exposed to sunlight and thus at risk of actinic keratosis and other skin malignancies?

Answer 13

• Face
• Ears
• Scalp
• Forearms
• Backs of hands

Question 14

How does actinic keratosis feel on palpation with gloves?

Answer 14

Like sandpaper

Question 15

Features of what may be seen around the actinic keratosis?

Answer 15

Solar damage

Question 16

What are the features of solar damage that may be seen in actinic keratosis?

Answer 16

• Notable pigmentary alterations
• Deep wrinkles
• Course texture of skin
• Dry skin
• Scattered telangiectasia

Question 17

What are the pigmentary alterations that can be seen around actinic keratosis?

Answer 17

Yellow or pale skin with some hyperpigmentation

Question 18

What are the different classifications of actinic keratosis?

Answer 18

• Common
• Hypertrophic
• Atrophic
• Cutaneous horn
• Pigmented
• Actinic chelitis

Question 19

What are the features of hypertrophic actinic keratosis?

Answer 19

• Thicker scale

- Rough plaque/papule

Question 20

What are the features of atrophic actinic keratosis?

Answer 20

• Lack of scale
• Appears as a non-palpable change in colour
• Smooth
• Red
• <10mm diameter

Question 21

What are the features of a cutaneous horn?

Answer 21

• Keratinic projection
• Height at least 1/2 of diameter
• Conical shape

Question 22

What are the features of pigmented actinic keratosis?

Answer 22

• Tan or brown

- Macules or papules

Question 23

How common is pigmented actinic keratosis?

Answer 23

It is a rare variant

Question 24

What is actinic chelitis?

Answer 24

When actinic keratosis forms on the lip

Question 25

Whit is actinic chelitis often accompanied by?

Answer 25

Sensation of a dry mouth and splitting of lips

Question 26

What appearance of actinic keratosis should raise suspicion of progression to malignancy?

Answer 26

- Ulceration - Nodularity - Bleeding

Question 27

How is actinic keratosis usually diagnosed?

Answer 27

Clinically with a dermatoscope

Question 28

When is a skin biopsy used in actinic keratosis?

Answer 28

When there are features causing suspicion of malignancy

Question 29

What are the differentials for actinic keratosis?

Answer 29

- BCC - SCC - Seborrhoeic keratosis - Bowen's disease - Amelanotic melanoma - Discoid lupus erythematosis

Question 30

What are the general conservative management techniques for actinic keratosis?

Answer 30

- Limit sun exposure - Use sun protection - Use emollients - Report changes to existing lesions - Report new lesions

Question 31

How can actinic keratosis be treated?

Answer 31

- Topical treatments | - Ablative treatments

Question 32

What topical treatments are available for actinic keratosis?

Answer 32

- 5FU cream | - Imiquimod cream

Question 33

What advice should be given when using topical treatments for actinic keratosis?

Answer 33

It may look worse before getting better

Question 34

What ablative therapies are available for actinic keratosis?

Answer 34

- Cryoptherapy - Photodynamic therapy - Curettage or excision

Question 35

What is the type of treatment for actinic keratosis dependent on?

Answer 35

- Clinical grade - Site - Number of lesions - Presence of field damage - Size of skin area affected

Question 36

What is cryotherapy useful for?

Answer 36

Single or multiple lesions without field damage

Question 37

What is photodynamic therapy useful for?

Answer 37

Individual lesions

Question 38

What is curettage or excisional surgery useful for?

Answer 38

Discrete hyperkeratotic lesions

Question 39

What is the important complication of actinic keratosis?

Answer 39

Progression to malignancy