Management of Actinic Keratosis on the Ears

Clinical Diagnosis

The presentation of rough, bumpy, scaly, slightly pearlescent lesions on sun-exposed areas, such as the ears, is pathognomonic for actinic keratosis, according to the British Journal of Dermatology 1, 2.
The ears are a high-risk location for actinic keratosis due to chronic UV exposure, particularly in men with thinning hair, as reported by the Journal of the American Academy of Dermatology 3.

Liquid nitrogen cryotherapy is the standard first-line treatment for individual actinic keratosis lesions on the ears, as recommended by the British Journal of Dermatology 1, 2.
Cryotherapy carries a 25% risk of ulceration and/or infection, particularly on the ears where healing can be delayed, according to the British Journal of Dermatology 4.
Photodynamic therapy (PDT) is considered for multiple actinic keratosis lesions at sites of poor healing, such as the ears, or with poor response to standard therapies, as suggested by the British Journal of Dermatology 1, 2.

The American Academy of Dermatology recommends performing biopsy if there is diagnostic uncertainty or failure to respond to first-line treatment, and any lesion with induration, ulceration, rapid growth, or diameter >1 cm warrants biopsy to exclude squamous cell carcinoma 1, 2, 3.
Strict sun avoidance and photoprotection are mandatory, as successful actinic keratosis treatment is associated with lower skin cancer incidence, according to the Journal of the American Academy of Dermatology 3.
The British Journal of Dermatology recommends schedule follow-up at 3-6 months initially, then every 6-12 months for total body skin examination, and educate the patient to self-monitor for new lesions or changes suggesting progression to SCC 1, 2.

The Journal of the American Academy of Dermatology advises against ignoring field cancerization, as treating individual lesions without addressing the entire sun-damaged field leads to continued development of new actinic keratosis lesions 3.
The American Academy of Otolaryngology-Head and Neck Surgery recommends avoiding neomycin-containing topical preparations, as 5-15% of patients with chronic external ear conditions develop contact sensitization 7.

For 1-5 discrete lesions, the British Journal of Dermatology recommends cryotherapy as first-line 1, 2.
For >5 lesions or confluent involvement, field-directed topical therapy (5-FU or imiquimod) is considered, as suggested by the British Journal of Dermatology 1, 2.
If treatment failure after 2-3 attempts, obtain biopsy to exclude SCC, according to the British Journal of Dermatology 1, 2.
If multiple recurrences or poor healing, consider PDT, as recommended by the British Journal of Dermatology 1, 2.
All patients should implement strict photoprotection and establish surveillance schedule, as advised by the British Journal of Dermatology and the Journal of the American Academy of Dermatology 1, 2, 3.