Actinic Keratosis Flashcards
What is actinic keratosis?
A pre-cancerous area of thick, scaly, or crusty skin
What is the underlying cause of actinic keratosis?
UV-induced DNA damage within the skin
How does sunlight cause DNA damage?
Photo-aging leads to an accumulation of oncogenic changes
What is the result of the oncogenic changes to skin cell DNA in actinic keratosis?
Proliferation of mutated keratinocytes that can manifest as actinic keratosis or other neoplastic growths
What are the three paths that actinic keratosis can take?
- Remain stable
- Progress to Bowen’s disease
- Progress to SCC
What are the risk factors for actinic keratosis?
- Fair skin
- Immunosuppression
- HPV
- Balding
What are the signs of a person who would be considered fair skinned?
- Freckling
- Light hair and eye colour
- Propensity to sunburn
- Inability to tan
What is the typical morphology of actinic keratosis?
White, scaly plaque of variable thickness with surrounding redness
What is the typical size of actinic keratosis?
2-6mm (can be several cm)
Are actinic keratosis lesions usually symptomatic?
No
What are the uncommon presenting symptoms of an actinic keratosis lesion?
- Tenderness
- Itching
- Bleeding
- Stinging or burning sensation
What parts of the body to actinic keratosis develop on?
Those exposed to sunlight
What parts of the body are exposed to sunlight and thus at risk of actinic keratosis and other skin malignancies?
- Face
- Ears
- Scalp
- Forearms
- Backs of hands
How does actinic keratosis feel on palpation with gloves?
Like sandpaper
Features of what may be seen around the actinic keratosis?
Solar damage
What are the features of solar damage that may be seen in actinic keratosis?
- Notable pigmentary alterations
- Deep wrinkles
- Course texture of skin
- Dry skin
- Scattered telangiectasia
What are the pigmentary alterations that can be seen around actinic keratosis?
Yellow or pale skin with some hyperpigmentation
What are the different classifications of actinic keratosis?
- Common
- Hypertrophic
- Atrophic
- Cutaneous horn
- Pigmented
- Actinic chelitis
What are the features of hypertrophic actinic keratosis?
- Thicker scale
- Rough plaque/papule
What are the features of atrophic actinic keratosis?
- Lack of scale
- Appears as a non-palpable change in colour
- Smooth
- Red
- <10mm diameter
What are the features of a cutaneous horn?
- Keratinic projection
- Height at least 1/2 of diameter
- Conical shape
What are the features of pigmented actinic keratosis?
- Tan or brown
- Macules or papules
How common is pigmented actinic keratosis?
It is a rare variant
What is actinic chelitis?
When actinic keratosis forms on the lip
Whit is actinic chelitis often accompanied by?
Sensation of a dry mouth and splitting of lips
What appearance of actinic keratosis should raise suspicion of progression to malignancy?
- Ulceration
- Nodularity
- Bleeding
How is actinic keratosis usually diagnosed?
Clinically with a dermatoscope
When is a skin biopsy used in actinic keratosis?
When there are features causing suspicion of malignancy
What are the differentials for actinic keratosis?
- BCC
- SCC
- Seborrhoeic keratosis
- Bowen’s disease
- Amelanotic melanoma
- Discoid lupus erythematosis
What are the general conservative management techniques for actinic keratosis?
- Limit sun exposure
- Use sun protection
- Use emollients
- Report changes to existing lesions
- Report new lesions
How can actinic keratosis be treated?
- Topical treatments
- Ablative treatments
What topical treatments are available for actinic keratosis?
- 5FU cream
- Imiquimod cream
What advice should be given when using topical treatments for actinic keratosis?
It may look worse before getting better
What ablative therapies are available for actinic keratosis?
- Cryoptherapy
- Photodynamic therapy
- Curettage or excision
What is the type of treatment for actinic keratosis dependent on?
- Clinical grade
- Site
- Number of lesions
- Presence of field damage
- Size of skin area affected
What is cryotherapy useful for?
Single or multiple lesions without field damage
What is photodynamic therapy useful for?
Individual lesions
What is curettage or excisional surgery useful for?
Discrete hyperkeratotic lesions
What is the important complication of actinic keratosis?
Progression to malignancy
