Actinic Keratoses: Reconciling the Biology of Field Cancerization with Treatment Paradigms

This Perspective briefly reviews the relationship between UV-induced mutations in habitually sun-exposed human skin and subsequent development of actinic keratoses (AKs) and skin cancers. It argues that field therapy rather than AK-selective therapy is the more logical approach to cancer prevention and hypothesizes that treatment early in the process of field cancerization, even prior to the appearance of AKs, may be more effective in preventing cancer as well as more beneficial for and better tolerated by at-risk individuals. Finally, the Perspective encourages use of rapidly advancing DNA analysis techniques to quantify mutational burden in sun-damaged skin and its reduction by various therapies.

Relative efficacy of 5-fluorouracil compared with other treatments among patients with actinic keratosis: A network meta-analysis

OBJECTIVE

The purpose of this study was to compare the efficacy of 5-fluorouracil (5-FU) with that of other treatments of actinic keratosis (AK).

METHODS

A systematic literature review of five databases (including Medline and EMBASE) was first performed to identify randomized controlled trials (RCTs). A network meta-analysis (NMA) based on a random-effects Bayesian model was then performed on the outcomes for patients with total clearance and lesions reduced from baseline. Five treatments (viz., 0.5% 5-FU with 10% salicylic acid [5-FU/SA], 5% 5-FU cream, 3% diclofenac sodium, cryosurgery, and vehicle) were evaluated.

RESULTS

A total of 11 studies involving 2,256 patients with AK were included in this NMA. The overall risk of bias among the included studies was low. All treatments were significantly better than the vehicle both for patients with total clearance and for lesions reduced from baseline. Among patients with total clearance, 5% 5-FU cream (56.8%) and 5-FU/SA (35.7%) were likely to be more effective than the other treatments, whereas 5% 5-FU cream (98.6%) was likely the most effective in the group of lesions reduced from baseline.

CONCLUSION

5-FU, diclofenac sodium, and cryosurgery are all useful for AK treatment, with 5-FU being the most effective.

Improved patient satisfaction using ingenol mebutate gel 0.015% for the treatment of facial actinic keratoses: a prospective pilot study

Actinic keratoses (AKs), especially on areas of the face, have a negative impact on a patient’s quality of life (QoL). These lesions manifest on sun-damaged skin and have the potential to progress to squamous cell carcinoma. Field-directed therapy alone and in combination with lesion-directed treatment is effective in clearing both visible and nonvisible AK lesions. Topical treatments of AKs thus have the potential to improve a patient’s well-being. However, evidence demonstrating improvements in patient QoL is limited, and is mostly based on observational or retrospective studies. Some prospective studies have reported unchanged or even worsening QoL despite excellent treatment outcomes. Our prospective, pilot study demonstrated a significant increase in QoL in 28 subjects with AKs of the face treated with ingenol mebutate gel 0.015%. QoL was assessed at days 0 and 60 using the Skindex-16 survey. Mean overall scores improved from 24.5% at baseline to 15.5% at day 60 (P=0.031). Improvements in QoL were consistent with an 80% reduction in AK lesion number at day 60. These improved QoL findings are in line with those from a recent retrospective study using ingenol mebutate 0.015% gel. This study therefore further demonstrates the potential for field therapy to improve both treatment outcomes and patient satisfaction.