New Treatment Options for Actinic Keratosis: What Does Microwave Ablation Add?

actinic keratosis in head of a man
actinic keratosis in head of a man
How do clinicians select the optimal treatment strategy for actinic keratoses when research supports multiple therapeutic directions?

Current treatment options for patients with actinic keratoses (AKs) were explored in a commentary piece published in the British Journal of Dermatology. As the most common precancerous skin lesions, AKs are often treated with lesion-directed therapy. New developments in the lesion therapy field offer potential advances in AK care, while also complicating physicians’ choices. How do clinicians select the optimal treatment strategy, when research supports multiple therapeutic directions?  

A feasibility study published in February 2020 described the treatment of AK with a microwave medical device. Microwave ablation has been previously used the treatment of inoperable liver and lung cancers, as well as in the removal of skin warts. In a study of patients with AKs, microwave ablation resolved 90% of AKs within 120 days of treatment. Clearance of AK lesions was limited to the area of application, which was 6 mm in diameter. Pain experienced by ablation was short lived and typically abated within hours of treatment application. The majority of patients reported that they preferred microwave ablation to their current treatment method.  

The diversity of available AK treatments has presented somewhat of a dilemma to physicians. Currently, cryotherapy is the most widely used therapy for single lesions. However, results from a 2019 study suggest that 5-fluorouracil (5-FU) cream may be the most effective field-directed treatment for AK. Other treatment options include photodynamic therapy, diclofenac gel, imiquimod cream, and ingenol mebutate gel. Where microwave ablation fits into this landscape remains unclear. Compared with cryotherapy, the microwave device requires less complex storage infrastructure, although it is more costly. It remains important to weigh the benefits and costs of each therapeutic option, while also considering patient acceptability and adherence. Further study is necessary to assess the long-term efficacy of microwave ablation, particularly compared with cryotherapy and topical gels. The combined effect of microwave ablation with these other therapies is also worth exploring.

Although selection of treatment becomes more difficult with the introduction of new, innovative devices, AKs require rapid and complete treatment. As precursors of cutaneous squamous cell carcinoma, AKs should be addressed with due care—with both new and existing treatments, if necessary. “In the search for an optimal strategy to manage AK, there is still room for a new treatment,” authors wrote. “[L]esion-directed therapies…deserve to remain in the field of investigation.”


Samimi M, Kelleners-Smeets N. Innovative devices for actinic keratoses: a hot-button issue [published online June 21, 2020]. Br J Dermatol. doi: 10.1111/bjd.19249