Current issues in the management of actinic keratosis

The cover of an ear thermometer probe as a split-thickness skin graft mold in external auditory canal reconstruction

Maintaining the patency of the external auditory canal (EAC) during reconstruction is important because of its physiological role in hearing and immunological protective functions. The curved shape of the EAC presents a challenge when performing a skin graft. One of the key points for a successful skin graft is to ensure compression on the wound bed, and many novel methods, including prefabricated ear molds, have been reported for this purpose. In this study, we present a case of a skin graft performed to reconstruct a skin defect following excision of actinic keratosis in the EAC, using the cover of an ear thermometer probe as a mold for the graft to match the curvature of the EAC. This is an economical and practical method for secure compression dressing of a skin graft in the EAC.

Actinic Keratoses (AK): An Exploratory Questionnaire-Based Study of Patients’ Illness Perceptions

Simple Summary

We recorded 208 patients receiving treatment for AK and conducted a cross-sectional questionnaire-based study, which aimed to investigate patients’ perceptions of their illness. Our main objective was the detection not only of the illness perception of AK patients, but also of its influence on their perception of treatment and the correlation with patients’ demographic characteristics and history, as well as the readiness to use sunscreen. The rising incidence of AK and its socioeconomic burden place the illness perception of AK patients among the most important barriers to overcome for the effective management of the disease. To the best of our knowledge, this is one of the first studies to attempt to unveil the illness perceptions of AK patients and their correlation with patients’ demographics and sunscreen use and the influence on AK treatment. We strongly support reinforcing the awareness of AK and the role of dermatologists is crucial for this direction.

Abstract

Background: Decreased illness perception among actinic keratoses (AK) patients is a major barrier to the effective management of AK. Objective: We aimed to investigate patients’ illness and treatment perceptions, their correlation to demographics and AK/skin cancer history, and secondarily the influence of these perspectives on treatment and sunscreen use. Materials and Methods: Participants completed questionnaires based on the Brief Illness Perception Questionnaire and statistical analysis was performed. Results: In total, 208 AK patients were enrolled. A large proportion were poorly aware of the disease (41.4%), with less than half (43%) being familiar with AK. Patients were aware of the chronic nature of the disease and its correlation to sunlight regardless of demographic characteristics. The level of education played a role in disease awareness (p = 0.006), and treatment plan perception (p = 0.002). The increase in sunscreen protection after AK diagnosis was higher in women (p = 0.009) and younger patients (p = 0.044). Patients’ concerns regarding treatment were mainly related to the duration (30%) and effectivity (25%). Dermatologists’ statements highlighting that AK are precancerous lesions (86.2%) influenced patients’ willingness for treatment. Conclusion: Improved awareness of AK is necessary to increase treatment seeking and compliance, regarding both treatment and sunscreen use. Dermatologists’ statements may have critical influence on patients’ decisions to receive treatment for AK.

Actinic keratosis (review of literature)

Actinic keratosis is an important medical and social problem, the correct diagnosis and treatment of which will help to avoid the development of invasive forms of cutaneous squamous cell carcinoma. With the further development of the early diagnosis of cancer, including skin cancer, the increase in human life expectancy, and the popularization of travel to exotic countries, the number of cases of actinic keratosis among the population will continue to grow. In this regard, it is important to discuss the causes and pathogenesis of the disease, the varied clinical picture of the disease, methods of non-invasive diagnostics, as well as methods of treatment, of which there are a great many in the treatment of actinic keratosis today. However, each of the methods has both advantages and disadvantages, and in the global trend towards a personalized approach to treatment, it is important to choose from the standpoint of evidence-based medicine the most suitable for each individual patient. Moreover, after treatment of actinic keratosis, relapses often occur, which are the result of insufficient diagnosis and the development of incorrect treatment tactics. The review article provides the clinical picture of actinic keratosis, diagnostic and therapeutic methods, and their comparison with each other in terms of efficacy and safety

Topical Pharmacotherapy for Actinic Keratoses in Older Adults

Actinic keratosis is caused by excessive lifetime sun exposure. It must be treated, regardless of thickness, because it is the biologic precursor of invasive squamous cell carcinoma, a potentially deadly malignancy. Physical ablative techniques such as cryotherapy, lasers, and curettage are the most used treatments for isolated lesions. Multiple lesions are treated with topical drugs, chemical peelings, and physical techniques. Drug preparations containing diclofenac plus hyaluronate, aminolevulinic acid, and methyl aminolevulinate and different concentrations of imiquimod and 5-fluorouracil are approved for this clinical indication. All treatments have a good profile of efficacy and tolerability although there are relevant differences in the clearance rate, tolerability, and type and frequency of adverse effects. In addition, they have very different mechanisms of action and treatment protocols. No differences in the efficacy and tolerability were found in older patients compared with younger patients, therefore no dose adjustments are needed. That said, older patients often need to be motivated to treat actinic keratoses and a careful attention to expectations, needs, and preferences should be used to obtain the maximal adherence and prevent treatment failure. This goal can be achieved with a careful evaluation not only of published efficacy, toxicity, and tolerability data but also of practical topics such as the frequency of daily applications, the overall duration of therapy, and the need for a caregiver. Finally, particular attention must be paid in the case of frail patients and immunosuppressed patients.

Clinical Pharmacokinetics and Safety of a 10% Aminolevulinic Acid Hydrochloride Nanoemulsion Gel (BF-200 ALA) in Photodynamic Therapy of Patients Extensively Affected With Actinic Keratosis: Results of 2 Maximal Usage Pharmacokinetic Trials

The nanoemulsion‐based 10% aminolevulinic acid (ALA) hydrochloride gel BF‐200 ALA optimizes epidermal penetration of its active ingredient and is approved for topical photodynamic therapy (PDT) for the treatment of actinic keratosis in the United States and Europe. To characterize systemic absorption from dermal application during PDT, ALA and its key active metabolite protoporphyrin IX (PpIX) were analyzed in 2 maximal usage pharmacokinetic trials (MUsT) in patients severely affected with actinic keratosis. The primary objective of both MUsTs was to assess baseline‐adjusted plasma concentration–time curves for ALA and PpIX after a single PDT treatment applying either 2 g (1 tube) of BF‐200 ALA on the face (MUsT‐1) or applying 6 g (3 tubes) of BF‐200 ALA on the face/scalp or body periphery (MUsT‐2), to 20 or 60 cm², respectively. All PDTs were performed using red light at around 635 nm wavelength. Safety and tolerability were documented along with pharmacokinetics. In both MUsTs, ALA plasma concentrations were transiently increased to a maximum concentration at about 2.5 to 3.3 times above endogenous baseline with time to maximum concentration at ≈3 hours after dosing. Plasma levels subsequently returned to baseline within 10 hours after dosing. Overall baseline‐adjusted mean area under the baseline‐adjusted plasma concentration‐time curve from time zero to the last sampling time point at which the concentration was at or above the lower limit of quantification ranged from 142.8 to 146.2, indicating that a similar, minor fraction of topical ALA is systemically absorbed under both dosing regimens. Systemic PpIX exposure after administration of either dose of BF‐200 ALA was equally minimal. Application site skin reactions were treatment area size‐related, albeit transient and consistent with the known safety profile of BF‐200 ALA.

Comparison of Grenz ray and photodynamic therapy for field treatment of actinic keratoses on the forearm: A case series

BACKGROUND

Actinic Keratosis is an intraepidermal neoplasm that represents the second most common reason for dermatologic visits in the United States. Sustained clearance with existing therapies is highly variable.

OBJECTIVE

To assess the effects of combination and monotherapy with photodynamic therapy (PDT), grenz ray therapy, and PDT with microneedling (microchannel skin system) for actinic damage of the dorsal forearms and hands.

METHODS

Full ethics approval was obtained through a Human Subjects Committee. Four patients with diffuse actinic field damage on their forearms and hands were recruited for the study. The dorsal forearm and hand from the elbow to the metacarpophalangeal joint were divided into four equal sections. Section 1 was treated with PDT. Section 2 was treated with grenz ray. Section 3 was treated with PDT plus microneedling. Section 4 was treated with grenz ray and PDT with microneedling. Lesion counts were recorded with transparent grids, photographed and evaluated by the same investigator at baseline, 1, 2, 3 and 6 months.

RESULTS

At month 6 post treatment, lesion counts, as a per cent reduction from baseline, were 91.7% in section 1 (PDT); 97.3% in section 2 (grenz ray); 92.9% in section 3 (PDT + microneedle); and 93.9% in section 4 (grenz ray + PDT + microneedle).

CONCLUSION

The greatest reduction occurred in the grenz ray monotherapy section and the second greatest reduction in the grenz ray, PDT, microneedling section. Further research on the efficacy of grenz ray therapy for field treatment of actinic keratosis of the forearms and hands is needed.

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.

Clinical, histopathological and immunohistochemical evaluation of daylight photodynamic therapy in the treatment of field cancerization: a study of 30 cases

BACKGROUND

Actinic keratosis (AK) are pre-malignant lesions, precursors of squamous cell carcinoma (SCC). Normal skin adjacent to AK, may present initial mutations with potential risk for new neoplasms, currently known today as field cancerization (FC).

OBJECTIVES

To evaluate the effectiveness of daylight photodynamic therapy (PDT) with methyl amino levulinate (MAL) based on clinical evaluation, histological examination and immunohistochemical expression of p53 and Ki67.

MATERIAL AND METHODS

Thirty patients, over 35 years old, phototypes between I and III, presenting non-hypertrophic AK on the face or scalp. Two biopsies with 2 mm punch of the lesion and adjacent skin before and 60 days after daylight PDT were performed. Results: Improvement was seen in lesion thickness and Ki67. 19 (63.33%) lesions had atypia improvement with a p-value <.05, showing efficacy in treatment. After daylight PDT, 22 (73.33%) patients showed satisfactory esthetic improvement.

CONCLUSION

The study shows that PDT has cellular and molecular effects that support its indication in the control of carcinogenesis, as it decreases atypia and controls the expression of Ki67, reducing the proliferation of atypical cells. However, its indication following this study is still mainly aimed at clinical improvement of the skin, at this moment, probably due to the sample size.

Current therapies for actinic keratosis

Actinic keratosis (AK) is a very common skin disease caused by chronic sun damage, which in 75% of cases arises on chronically sun-exposed areas, such as face, scalp, neck, hands, and forearms. AKs must be considered an early squamous cell carcinoma (SCC) for their probable progression into invasive SCC. For this reason, all AK should be treated, and clinical follow-up is recommended. The aims of treatment are: (i) to clinically eradicate evident and subclinical lesions, (ii) to prevent their evolution into SCC, and (iii) to reduce the number of relapses. Among available treatments, it is possible to distinguish lesion-directed therapies and field-directed therapies. Lesion-directed treatments include: (i) cryotherapy; (ii) laser therapy; (iii) surgery; and (iv) curettage. Whereas, field-directed treatments are: (i) 5-fluorouracil (5-FU); (ii) diclofenac 3% gel; (iii) chemical peeling; (iv) imiquimod; and (v) photodynamic therapy (PDT). Prevention plays an important role in the treatment of AKs, and it is based on the continuous use of sunscreen and protective clothing. This review shows different types of available treatments and describes the characteristics and benefits of each medication, underlining the best choice.

Actinic keratoses: review of clinical, dermoscopic, and therapeutic aspects

Actinic keratoses are dysplastic proliferations of keratinocytes with potential for malignant transformation. Clinically, actinic keratoses present as macules, papules, or hyperkeratotic plaques with an erythematous background that occur on photoexposed areas. At initial stages, they may be better identified by palpation rather than by visual inspection. They may also be pigmented and show variable degrees of infiltration; when multiple they then constitute the so-called field cancerization. Their prevalence ranges from 11% to 60% in Caucasian individuals above 40 years. Ultraviolet radiation is the main factor involved in pathogenesis, but individual factors also play a role in the predisposing to lesions appearance. Diagnosis of lesions is based on clinical and dermoscopic examination, but in some situations histopathological analysis may be necessary. The risk of transformation into squamous cell carcinoma is the major concern regarding actinic keratoses. Therapeutic modalities for actinic keratoses include topical medications, and ablative and surgical methods; the best treatment option should always be individualized according to the patient.

Review of Clinical Evidence over 10 Years on Prevention and Treatment of a Film-Forming Medical Device Containing Photolyase in the Management of Field Cancerization in Actinic Keratosis

Abstract

Actinic keratosis (AK) is a common pathology that afflicts sun-exposed areas of the skin. It predominantly affects older and fair-skinned individuals suggesting an accumulative damage attributable to chronic sun exposure. The prevalence of AK has risen in the past decades and is expected to continue to rise. Apart from visible hyperkeratotic, hyperplastic lesions, AK is also associated with the presence of subclinical lesions adjacent to tumor tissue, which has led to the use of the concept “cancerization field”. Although lesion- and field-targeting treatments are currently available, many are associated with local side effects and recurrence of new lesions. This review provides information on AK pathophysiology and treatment options and summarizes the available clinical evidence supporting the use of Eryfotona AK-NMSC, a film-forming medical device with SPF 100+ containing the DNA repair enzyme photolyase, for managing AK, based on the analysis of the results of 228 patients treated with the product.

Funding

ISDIN funded the Article Processing Charges.

Electronic supplementary material

The online version of this article (10.1007/s13555-019-0294-1) contains supplementary material, which is available to authorized users.

Skin cancer precursor immunotherapy for squamous cell carcinoma prevention

BACKGROUND

Topical calcipotriol plus 5-fluorouracil (5-FU) combination is an effective immunotherapy against actinic keratosis (AK), which is a precursor to squamous cell carcinoma (SCC). However, the long-term effectiveness of calcipotriol plus 5-FU treatment for SCC prevention is unknown.

METHODS

We performed a blinded prospective cohort study on participants of a randomized double-blind clinical trial in which a 4-day course of topical calcipotriol plus 5-FU combination was compared to Vaseline plus 5-FU (control) for AK treatment. SCC and basal cell carcinoma (BCC) incidences were assessed at 1, 2, and 3 years after trial. Tissues were analyzed for calcipotriol plus 5-FU-induced T cell immunity in the skin.

RESULTS

Calcipotriol plus 5-FU-induced tissue-resident memory T (Trm) cell formation in face and scalp skin associated with significantly higher erythema scores compared with control (P < 0.01). Importantly, more participants in the test cohort remained SCC-free over the more than 1,500-day follow-up period (P = 0.0765), and significantly fewer developed SCC on the treated face and scalp within 3 years (2 of 30 [7%] versus 11 of 40 [28%] in control group, hazard ratio 0.215 [95% CI: 0.048-0.972], P = 0.032). Accordingly, significantly more epidermal Trm cells persisted in the calcipotriol plus 5-FU-treated face and scalp skin compared with control (P = 0.0028). There was no significant difference in BCC incidence between the treatment groups.

CONCLUSION

A short course of calcipotriol plus 5-FU treatment on the face and scalp is associated with induction of robust T cell immunity and Trm formation against AKs and significantly lowers the risk of SCC development within 3 years of treatment.

FUNDING

This research was supported by internal academic funds and by grants from the Burroughs Wellcome Fund, Sidney Kimmel Foundation, Cancer Research Institute, and NIH.

Current developments in pharmacotherapy for actinic keratosis

INTRODUCTION

Actinic keratosis (AK) is a superficial squamous cell carcinoma (SCC) where chronic sun exposure playing central role in its pathogenesis. UVB causes direct damage to DNA, producing pyrimidine dimers, and suppressing the protective role of p53. The stepwise progression of AK, with increased expression of anti-apoptotic Bcl-2, favors progression to SCC. Moreover, the dermal response characterized by inflammation and mediated by prostaglandins is a critical component of tumorigenesis that promotes tumor growth, tissue invasion, angiogenesis and metastasis. Other risk factors are represented by age, gender, phototype and drugs.

AREAS COVERED

In this review, the authors document the recent developments of different therapies used to treat AK and provide their perspectives on current and future treatment strategies.

EXPERT OPINION

The usefulness of long-term treatment with piroxicam and sun filters or diclofenac targeting the inflammation phases of skin tumorigenesis favors AK's healing and provides greater control of the cancerization field. Nonsteroidal anti-inflammatory drugs can be safely used in patients who use photosensitizing drugs and, therefore, are more at risk of developing skin tumors. Immunomodulatory therapies, which require shorter treatment, are characterized by more common local side effects, and need more attention by the dermatologist in the concern of patient education, resulting essential to improve adherence and outcomes.

The safety and efficacy of daylight photodynamic therapy in the treatment of actinic keratoses: a systematic review and meta-analysis

Daylight photodynamic therapy (DLPDT) is a novel therapeutic approach for actinic keratoses (AKs). This study aimed to evaluate the safety and efficacy of DLPDT in treating patients with AKs as compared to conventional photodynamic therapy (CPDT). PubMed, EMBASE, Web of Science, and the Cochrane Central Register of Controlled Trials were searched for relevant randomized controlled trials (RCTs) published before November 2017, based on the following search terms: "solar keratoses", "actinic keratoses", "photodynamic therapy", "daylight photodynamic therapy", "conventional photodynamic therapy", and "randomized". The complete response rate, patient satisfaction, and patient-reported pain after intervention with DLPDT or CPDT were primarily measured. Sensitivity analysis was conducted to determine the reliability of results. Begg's and Egger's tests were used to assess the likelihood of publication bias. Eight RCTs, comprising a total of 424 patients with AKs treated with DLPDT or CPDT, were included. No significant difference was found between the lesion response rate and the mean lesion response in a comparison of DLPDT and CPDT treatments. Generally, DLPDT was associated with higher patient satisfaction than CPDT. The patients who underwent DLPDT experienced less pain than those who underwent CPDT. Most of our results were of high stability and low sensitivity. Meanwhile, no statistical evidence of publication bias among studies was found under all comparisons. In conclusion, DLPDT is a safe and effective therapy, which could help in selecting the most appropriate therapeutic method for treating AKs and in guiding physicians to optimize treatment strategies.

Effect of ingenol mebutate on actinic keratosis in a Korean population: A prospective clinical, dermoscopic and histopathological study from a single center

Actinic keratosis (AK) is an in situ squamous cell carcinoma which is mostly found on sun-damaged skin, and it is prevalent among Caucasians. However, there is a lack of research on evaluating the treatment efficacy of ingenol mebutate (IM) on AK in Asians. This study was intended to analyze the treatment outcomes of IM on AK in Korean patients with regards to clinical, dermoscopic and histopathological aspects. A prospective study on 46 Korean patients who were diagnosed with AK and treated with IM was conducted. Clinically, 80% (24/30) of the patients showed an improvement at 8 weeks. Twenty out of the 30 (66.7%) patients were found to have achieved histopathological clearance. All local skin responses had disappeared at T4 in all patients. Patients with Fitzpatrick skin type III were proven to exhibit better treatment outcomes, both clinically (P = 0.001) and histopathologically (P = 0.001), than those with Fitzpatrick skin type IV. The clinical and histopathological clearance rate of AK with IM in Korean patients was 80% and 66.7%, respectively. The patients with Fitzpatrick skin type IV showed a tendency to have residual AK, histopathologically after treatment with IM. In conclusion, IM could be an effective and safe treatment option on AK in Korean patients. In addition, it would be helpful to carry out a cautious check-up when treating AK with IM in patients with a darker skin color.

Quality of Life, Behaviour and Attitudes towards Actinic Keratosis in Spain: The PIQA Study

OBJECTIVE

This study was aimed to examine patients' knowledge, behaviours and attitudes regarding actinic keratosis (AK) lesions and the impact of the disease on patients' quality of life (QoL).

METHODS

Observational study of patients with AK lesions in Spain. QoL was evaluated with the validated version of Spanish AKQoL questionnaire. Skin self-examination, sun-exposure, habits and attitudes towards AK's treatment were recorded using different questionnaires. The adherence was assessed by means of the Morisky-Green test. Among other variables, QoL and adherence to treatment were compared by using Pearson's χ² test and one-way ANOVA tests. Inferential analysis regarding such factors and length of treatment were also performed.

RESULTS

A total of 1240 patients (73.6 [10.5] years old) were recruited. Overall, patients that showed higher levels of concern were also showed a higher impairment on QoL. AK had greater effects on women's QoL and those who performed skin self-examination, think that AK is a disease and/or believe that moisturizers can prevent skin aging (P<.05). Adherence and length of treatment were strongly related, since patients with treatments intended for <1week were more likely to show good adherence and complete remission of AK (Odds Ratio [95%CI]: 6.25 [4.55-8.33] and 2.63 [1.96-3.45]), respectively).

CONCLUSIONS

Concerns due to AK are mainly related to sex and to the consideration of AK as a disease. More concerned patients tend to have lower QoL and good adherence to treatment. Short length of treatment was associated with better adherence and complete remission of AK lesions.

Daylight-Mediated Photodynamic Therapy With Methyl Aminolevulinate in Actinic Keratosis Treatment

BACKGROUND

Research has shown daylight-mediated photodynamic therapy (PDT) for the treatment of actinic keratosis (AK) to be effective, tolerable, and convenient, with excellent patient satisfaction and cosmesis. Although success has been demonstrated in areas with similar latitudes to Switzerland and Scandinavia, this treatment has not been studied in a Canadian population.

OBJECTIVES

The purpose of this study is to investigate the effectiveness, safety, and patient satisfaction of daylight-mediated methyl 5-aminolevulinate (MAL)-PDT to make recommendations for its use in Canadian practice.

METHODS

A retrospective chart review of patients who received treatment of daylight-mediated MAL-PDT for the indication of AK at the Institute of Cosmetic and Laser Surgery in Oakville, Ontario, between 2009 and 2016.

RESULTS

A total of 112 patients were included, consisting of 94 males and 18 females with a mean age of 63.79 years. A total of 177 sites were treated among all patients, mostly consisting of the face (n = 92) and scalp (n = 55). A total of 13.4% of patients experienced side effects, the most common being redness (n = 4) and scabbing (n = 4). Of the 42 patients who expressed their level of satisfaction, 83.3% reported being happy with the treatment, χ²(1) = 18.67, P ≤ .05; 6.3% of patients were noted to be completely clear, 86.6% had a good response, 0.9% had a mild response, and 0% had no response, χ²(1) = 101.04, P ≤ .05.

CONCLUSIONS

Daylight-mediated MAL-PDT is a suitable treatment option for AK lesions in a Canadian population due to the demonstrated efficacy, patient satisfaction, tolerability, and convenience.

Pharmacokinetics and Safety of Ingenol Disoxate Gel Administered Under Maximum-Use Conditions to Patients With Actinic Keratosis

BACKGROUND AND OBJECTIVES

Ingenol disoxate (LEO 43204) is a field therapy in development for the treatment of actinic keratosis (AK) on areas between 25 and 250 cm². We evaluated the systemic exposure and safety of ingenol disoxate under maximum-use conditions.

METHODS

This was a phase I, open-label, non-randomized, multicenter trial. Patients ≥ 18 years of age with ≥ 15 clinically typical, visible, discrete AK lesions in a treatment area on the full face or approximately 250 cm² on the arm or scalp were treated once-daily for 3 consecutive days with ingenol disoxate 0.018, 0.1, or 0.037% gel, respectively.

RESULTS

The trial included 58 patients. Median age (range) of patients was 68 years (42-89) [face, N = 18], 66 years (43-88) [arm, N = 21], and 67 years (37-83) [scalp, N = 19]. The highest quantifiable ingenol disoxate level was observed in the arm group (0.33 nM, area under the concentration-time curve from time zero to the last data point [AUC_tlast] 3.12 nM·h). Mean composite local skin response scores peaked at Day 4 and declined towards baseline by Day 15 in all treatment groups. Most adverse events (AEs) were of mild or moderate intensity; the most common treatment-related AEs were application-site pain (face, 88.9%; arm, 57.1%; scalp, 100.0%) and application-site pruritus (face, 50.0%; arm, 52.4%; scalp, 42.1%).

CONCLUSION

Very low systemic exposure to ingenol disoxate was observed when applied to the face, arm, or scalp in patients with AK under maximum-use conditions. No new safety signals were identified.

TRIAL REGISTRATION

NCT02424305.

Treatment considerations in actinic keratosis

The chronic skin condition actinic keratosis (AK) is characterized by the formation of keratotic lesions of variable thickness that are poorly delimited. AK occurs on areas of the skin that have had long-term exposure to the sun or UV radiation. Although AKs may regress, they usually persist and can progress to squamous cell carcinoma (SCC). Clinicians are unable to predict which AKs will progress; therefore, both clinically visible lesions and subclinical, non-visible (i.e. the entire area affected by AK/field cancerization) should be treated. AK treatment options include lesion-directed therapies that target specific AK lesions and field-directed therapies that target multiple clinical lesions and the underlying field damage. This article reviews currently available treatment options in AK, with a focus on patient-applied field therapies, and their suitability according to specific disease characteristics and patient needs. Choice of treatment in AK depends on lesion-, patient- and treatment-related factors and should be individualized. Considerations when choosing a therapy include site of application, treatment duration, surface area of application, tolerability profiles and implications on adherence. Field-directed therapies treat clinical and subclinical damage (i.e. the entire area affected by AK), achieve high rates of sustained clearance of AKs and may reduce the risk of progression to SCC. There is a clear need for field therapies with short duration of treatment and predictable, short-lived, mild local skin reactions that can be used over a large surface area. Therapies with shorter and simpler treatment courses are often associated with better adherence than treatments with longer courses. These may, therefore, represent more appropriate choices in patients for whom convenience and/or adherence are an issue.

The importance of patient-centred care to overcome barriers in the management of actinic keratosis

Visible actinic keratosis (AK) lesions and subclinical (non-visible) sun damage in the field of cancerization are associated with risk of both non-melanoma skin cancer, including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), and, more rarely, melanoma. As the incidences of AK and skin cancer are increasing, effective prevention and treatment of AK is essential to minimize disease burden and improve patient quality of life. Currently, AK lesions are often left untreated and field therapies are underused. Patient-centred care, with a focus on the patient-physician relationship, has proven cost-effective, and improved clinical outcomes and patient satisfaction in a number of therapy areas. Strategies for applying patient-centred care to AK are warranted. Existing barriers to the effective treatment of AK were identified and patient-centric strategies to overcome each barrier were discussed. Barriers to effective AK treatment include poor disease awareness (for both patient and physician), concerns associated with the cosmetic effects of treatment, treatment-related side effects, cost perceptions for lesion-directed vs field-directed therapies, and inadequate adherence, particularly with long treatment duration. Overcoming these barriers will involve patient and physician education that promotes: disease prevention and awareness; the importance of self-examination; an understanding of treatment options; and the importance of adherence to treatment. To maximize its effectiveness, education should be delivered within a patient-centric framework, where the relationship between patient and physician is built on effective communication, empathy and a feeling of partnership. Patient-centric care, including patient education, is key to overcoming the barriers associated with effective AK treatment.

A review of BF-200 ALA for the photodynamic treatment of mild-to-moderate actinic keratosis

BF-200 ALA is a combination of a nanoscale-lipid vesicle formulation and the prodrug 5-aminolevulinic acid (5-ALA). The nanoemulsion stabilizes the prodrug and enhances its penetration through the stratum corneum. It has shown excellent therapeutic results in both lesion and field-directed photodynamic therapy of actinic keratosis (AK). AK is an early form of epidermal neoplasia and a precursor of invasive cutaneous squamous cell carcinoma. It is characterized by the combination of visible neoplastic lesions and surrounding tissue also harboring tumorigenic UV-induced mutations: a concept called field cancerization. A selective, field-directed treatment is ideal to meet the requirements of field change. Here, we review the clinical data on BF-200 ALA for AK along with a summary of molecular mechanisms and future perspectives.

Imiquimod in dermatology: an overview

Imiquimod is an immune response modifier commercially available as a 3.75 and 5% cream. Topical imiquimod stimulates the innate and adaptive immune responses and induces cytokine production. This allows its use for the treatment of a wide variety of benign and malignant skin conditions due to its potential antiviral, antitumor, and immunoregulatory effects. Currently, topical imiquimod is US Food and Drug Administration (FDA)-approved for the treatment of anogenital warts, actinic keratosis, and superficial basal cell carcinomas. However, it has also shown a beneficial effect in the treatment of many other skin disorders. In this review, we describe existing evidence on the mechanism of action of topical imiquimod, its FDA-approved indications, off-label uses, and side effects.

Patient-reported outcomes in topical field treatment of actinic keratosis in Swedish and Danish patients

Topical treatments in dermatology can be long, complex and lead to nonadherence and nonpersistence to prescribed treatment. Clinical efficacy observed in randomized clinical trials (RCT) may therefore be reduced in real-world clinical practice. The objective of this study was to analyze patient-reported treatment adherence, treatment satisfaction and health-related quality of life (HRQoL) with topical treatments of actinic keratosis (AK) in routine clinical practice in Denmark and Sweden. Adult patients prescribed field-directed topical AK treatments with diclofenac gel, imiquimod or ingenol mebutate per routine clinical practice were eligible for the observational RAPID-ACT study. Data were collected through physician and patient questionnaires that included validated instruments to measure treatment satisfaction (TSQM-9), treatment adherence (MMAS) and HRQoL (EQ-5D-5L, EQ-VAS, AKQoL). In total, 446 patients from Denmark and Sweden were included. Ingenol mebutate patients reported a higher satisfaction with treatment effectiveness compared to patients treated with diclofenac (p = .006) while no other differences in treatment satisfaction could be determined. Treatment adherence was generally high, but higher for ingenol mebutate compared to both diclofenac (p < .001) and imiquimod (p = .007), possibly due to shorter treatment duration. No differences in improved HRQoL were found. More research is needed about the link between treatment adherence and real-world effectiveness.

Pharmacokinetics of ingenol mebutate gel under maximum use conditions in large treatment areas

PURPOSE

Actinic keratoses (AKs) exist on a continuum with squamous cell carcinoma and can occur as sub-clinical and clinically visible lesions in cancerized fields on sun-damaged skin. Ingenol mebutate effectively treats AKs on areas up to 25 cm², but actinic keratosis can affect larger areas of skin. This trial evaluated systemic exposure and safety of ingenol mebutate gel on larger areas of skin under maximum use conditions.

METHODS

Phase I, multicenter, open-label, uncontrolled, non-randomized trial. Patients received ingenol mebutate gel for three consecutive days on approximately 250 cm² of sun-damaged skin on the full face (0.027%), the scalp (0.027%), or arm (0.06%).

RESULTS

Of 61 patients, 10 (face =8; arm =2) had ingenol mebutate in whole blood at subnanomolar levels (0.235-0.462 nM). The assayed metabolites were below the lower limit of quantification. Local skin responses increased during Days 1-4 and declined thereafter, approaching baseline by Day 16. Most adverse events were pain/pruritus of mild or moderate intensity.

CONCLUSIONS

Subnanomolar systemic exposure to ingenol mebutate was measured after application of the gel to approximately 250 cm² on the full face, scalp, or arm under maximum use conditions. No clinically relevant systemic adverse reactions were observed, and local skin responses were manageable.

Patient satisfaction and reported outcomes on the management of actinic keratosis

Actinic keratosis (AK) is a common dermatologic condition in which hyperplastic epidermal lesions develop in response to excessive and chronic exposure to ultraviolet (UV) radiation. If left untreated, AK can progress to squamous cell carcinomas of the skin. Incidence is rising worldwide as a result of the progressive aging of populations and an increase in lifetime cumulative exposure to UV radiation. Currently, various treatment options exist, which range from topical medications to light-based therapies and procedural modalities. In this article, we will review the treatment options for AK with a focus on assessments of patient satisfaction with treatment.

Comparison of the Treatment Guidelines for Actinic Keratosis: A Critical Appraisal and Review

There are currently several reputable guidelines on the treatment of actinic keratosis (AK) from groups in Canada, the United Kingdom, and Europe. These recommendations, based on evidence or expert consensus, offer clinicians a variety of treatment options for the different clinical presentations of AKs. Although the guidelines are similar in some regards, variations exist in treatment options, duration, and strength of recommendation. Some guidelines also lack input on specific therapies and certain types of AK, such as hypertrophic or thin presentations. The purpose of this article is to review and compare guidelines published by Canadian, UK, and European groups for the management of AKs in patients.

Pharmacoeconomic Considerations in Treating Actinic Keratosis: An Update

Actinic keratosis is one of the most common dermatological diagnoses worldwide, especially among the elderly, fair-skinned, and immunocompromised, and is associated with a risk of transformation to skin cancer. With actinic keratosis and skin cancer prevalence increasing as the aged population expands in the US, optimizing treatment strategies may produce cost savings for the healthcare system. Since the time of our last review in 2008, investigation of the economic considerations in treating actinic keratosis has advanced. To provide an update of treatment cost effectiveness and to review factors relating to the costs of care, we conducted a systematic review of pharmacoeconomic publications since December 2008. We identified 11 pharmacoeconomic studies, with one cost-of-treatment, five cost-effectiveness, and five cost-utility analyses. Photodynamic therapy (PDT) was well tolerated and produced a favorable cosmetic outcome in most studies. Ingenol mebutate, the newest but most expensive topical field therapy, 5-fluorouracil, and PDT were the most cost-effective treatments in our review. Patient adherence to therapy and the management of adverse effects were significant contributors to treatment costs. In the US, treatment guidelines and formalized cost-effectiveness analyses for actinic keratosis are absent from the recent literature. Future pharmacoeconomic investigation will depend on up-to-date comparative efficacy data, as well as clarification of rates of, and management strategies for, adverse effects, therapeutic non-adherence, and lesion recurrence.

Thickness of Actinic Keratosis Does Not Predict Dysplasia Severity or P53 Expression

The severity of dysplasia and expression of p53 in actinic keratosis (AK) is of importance for the transformation to squamous cell carcinoma. It is assumed that it is most important to treat thick AKs as they are believed to be more dysplastic than thin AKs. However, a relation between AK thickness and dysplasia or the expression of p53 has never been demonstrated. The aim of this study was to investigate this possible relation. Sixty-six AKs were included for clinical and histological examination. Prior to performing a punch biopsy, the clinical thickness of each AK was measured objectively using two scale bars with a thickness of 0.5 mm and 1 mm. Subsequently, the thickness of the epidermis, the severity of dysplasia and the expression of p53 were assessed histologically. We found a strong and significant positive correlation between measured clinical thickness of the AKs and the histological thickness of epidermis (p < 0.0001). However, the clinical thickness did not correlate with either the severity of dysplasia (p = 0.7) or the expression of p53 (p = 0.5). In conclusion, thin AKs show the same severity of dysplasia and expression of p53 as thicker AK lesions. Consequently, clinical thickness cannot predict aggressiveness.

Efficacy and safety of follow-up field treatment of actinic keratosis with ingenol mebutate 0·015% gel: a randomized, controlled 12-month study

BACKGROUND

Ingenol mebutate (IngMeb) is a novel patient-applied topical field therapy for actinic keratosis.

OBJECTIVES

To demonstrate the efficacy and safety of follow-up IngMeb field treatment of actinic keratoses (AKs) present at 8 weeks after initial treatment or emerging in a previously cleared field.

METHODS

In this phase III, randomized, double-blind study in patients with 4-8 clinically visible AKs within a contiguous 25-cm(2) treatment area on the face or scalp, all patients were treated initially with IngMeb 0·015% gel for three consecutive days. If lesions were present in the field at 8 weeks, or emerged at weeks 26 or 44, patients were randomized (2 : 1) to follow-up IngMeb or vehicle gel for three consecutive days. The main outcome was complete clearance rates of AKs 8 weeks after randomization.

RESULTS

Of 450 patients who received initial treatment with IngMeb, 61·6% demonstrated complete clearance at 8 weeks. Patients with AKs present at 8 weeks or emerging at weeks 26 or 44 were randomized to IngMeb (n = 134) or vehicle (n = 69). IngMeb achieved a higher complete clearance rate than vehicle 8 weeks after randomization in AKs present at 8 weeks (46·7% vs. 18·4%; P < 0·01) and in emergent AKs (59·5% vs. 25·0%; P = 0·01). Based on those who completed 12 months of follow-up (n = 340), the overall 12-month clearance rate was estimated at 50·0%. Follow-up IngMeb treatment was well tolerated.

CONCLUSIONS

This study demonstrated the long-term benefit of IngMeb 0·015% gel for initial and follow-up therapy of AKs.

The acceptance of mobile teledermoscopy by primary care nurse practitioners in the state of Arizona

PURPOSE

To conduct a pilot survey to assess acceptance of mobile teledermoscopy (MTD) by primary care nurse practitioners (NPs) working in Arizona.

DATA SOURCES

Sixty-two participants recruited from NP and academic listservs in Arizona completed an online survey prefaced by a MTD definition, device photographs, and a practice case, followed by 33 items measuring Teledermatology Technology Acceptance Model (TeleTAM) constructs.

CONCLUSIONS

Participants were highly interested in using MTD to assess skin lesions. They perceived MTD utility to greatly improve diagnosis and positively impact their practice. Most participants had never used MTD, but had high mean scores for MTD attitude and moderate scores for MTD perceived ease of use, perceived use, and facilitators of MTD. They had moderate scores for intention to use MTD. The construct facilitators (organizational infrastructure) were most strongly associated with intention to use MTD. Cronbach alphas were 0.70 or higher for all subscales except compatibility and habit.

IMPLICATIONS FOR PRACTICE

Moderate acceptance of MTD may reflect NPs' knowledge of the technology, self-confidence for using it, or MTD financial constraints. Future research will address these factors to foster use of MTD by NPs, thereby improving patients' access to early skin lesion assessment and diagnosis.

Daylight photodynamic therapy with methyl aminolevulinate cream is effective and nearly painless in treating actinic keratoses: a randomised, investigator-blinded, controlled, phase III study throughout Europe

BACKGROUND

Unmet needs exist in actinic keratosis (AK) treatment. Daylight photodynamic therapy (DL-PDT) has shown good efficacy and safety results compared to conventional PDT (c-PDT) in a recent Phase III multi-centre randomised controlled trial in Australia among 100 subjects with AKs.

OBJECTIVES

Demonstrate non-inferior efficacy and superior safety of DL-PDT compared to c-PDT in treating multiple mild and/or moderate facial/scalp AKs.

METHODS

Phase III, 12 week, multi-centre, randomised, investigator-blinded, controlled, intra-individual study conducted at different latitudes in Europe. AKs of adult subjects were treated once with methyl aminolevulinate (MAL) DL-PDT on one side of the face and MAL c-PDT contralaterally. Endpoints for DL-PDT concerned efficacy (non-inferiority regarding complete lesion response at week 12) and safety (superiority regarding subject's assessment of pain after treatment, on an 11-point numeric rating scale). Safety evaluation also included incidence of adverse events. Subject satisfaction was described using a questionnaire at baseline and last visit.

RESULTS

At week 12, the total lesion complete response rate with DL-PDT was similar (non-inferior) to c-PDT (70% vs. 74%, respectively; 95% CI [-9.5; 2.4] in PP analysis, confirmed in ITT analysis). In addition, efficacy of DL-PDT was demonstrated regardless of weather conditions (sunny or cloudy). DL-PDT was nearly painless compared to c-PDT (0.7 vs. 4.4, respectively; P < 0.001), better tolerated and resulted in higher subject satisfaction.

CONCLUSION

DL-PDT in comparison with c-PDT was as effective, better tolerated and nearly painless with high patient satisfaction, and may be considered a treatment of choice to meet needs of patients with mild or moderate facial/scalp AKs.

Comprehensive review on betulin as a potent anticancer agent

Numerous plant-derived substances, and their derivatives, are effective antitumour and chemopreventive agents. Yet, there are also a plethora of tumour types that do not respond, or become resistant, to these natural substances. This requires the discovery of new active compounds. Betulin (BE) is a pentacyclic triterpene and secondary metabolite of plants abundantly found in the outer bark of the birch tree Betulaceae sp. BE displays a broad spectrum of biological and pharmacological properties, among which the anticancer and chemopreventive activity attract most of the attention. In this vein, BE and its natural and synthetic derivatives act specifically on cancer cells with low cytotoxicity towards normal cells. Although the antineoplastic mechanism of action of BE is not well understood yet, several interesting aspects of BE's interactions are coming to light. This review will summarize the anticancer and chemopreventive potential of BE in vitro and in vivo by carefully dissecting and comparing the doses and tumour lines used in previous studies, as well as focusing on mechanisms underlying its activity at cellular and molecular level, and discuss future prospects.

Lack of activity of betulin-based Oleogel-S10 in the treatment of actinic keratoses: a randomized, multicentre, placebo-controlled double-blind phase II trial

BACKGROUND

Betulinic acid and other triterpenes have shown strong antitumour activity in vitro and in vivo. A triterpene extract of birch bark formed the base of Oleogel-S10 and allowed topical application. Two previous trials have shown efficacy and tolerability in the treatment of actinic keratoses (AKs) with betulin-based Oleogel-S10.

OBJECTIVES

To confirm the efficacy and tolerability/safety of Oleogel-S10 in the treatment of AKs in a multicentre placebo-controlled study.

METHODS

Patients (n = 165) were treated topically for 3 months in a four-arm parallel study design, randomly allocated to A (n = 53) Oleogel-S10 once daily, B (n = 51) Oleogel-S10 twice daily, or C (n = 25) or D (n = 28) placebo (petroleum jelly) once or twice daily, respectively. Clinical efficacy in this double-blind study was assessed by the investigators. Final and baseline biopsies were evaluated by central histopathology.

RESULTS

Complete clearance of the target lesions was seen in 4% of patients in group A and 7% in group B, but not in the placebo groups. A clearance rate of > 75% was seen for 15% and 18% of patients in groups A and B, respectively, and for 13% in the placebo groups. These differences were not statistically significant. Histopathologically, 43·9% of patients showed a downgrading or clearance of the marker AK with no significant differences between the groups. Treatment with Oleogel-S10 was well tolerated. The tolerability as assessed by the investigator was mostly 'very good' (78·8%), followed by 'good' (18·2%) and only 1·2% assessed it as 'intolerable'. Patient-assessed tolerability was graded mostly 'very good' (56·4%) or 'good' (34·5%).

CONCLUSIONS

Treatment with Oleogel-S10 was well tolerated during a treatment period of 3 months, yet was no better than placebo in terms of efficacy in the treatment of AKs.

Primary care review of actinic keratosis and its therapeutic options: a global perspective

Actinic keratosis (AK) is a common skin condition caused by long-term sun exposure that has the potential to progress to non-melanoma skin cancers. The objective of this review is to examine the therapeutic options and management of AK globally, particularly in Australia, Canada, and the United Kingdom. Despite its potentially malignant nature, general awareness of AK is low, both in the general population and in the primary health care setting, especially in countries with low incidence. There is no standard therapeutic strategy for AK; it is treated through a variety of lesion-directed or field-directed therapies or a combination of both. A variety of treatment options are used depending on the experience of the primary care physician, the pathology of the lesion, and patient factors. Studies have shown that the physicians do not always use the optimal treatment option because of a lack of knowledge. The higher incidence of AK in fair-skinned people in Australia has resulted in well-established management strategies and guidelines for its treatment, compared with countries with lower incidence. It is essential to raise the awareness of AK because of its potential to progress to invasive squamous cell carcinoma. Primary care physicians are often the first to see this condition in their patients and are perfectly placed to educate the public and raise awareness. It is therefore desirable that their education and knowledge about AK and its treatment are up to date.

A randomized, double-blind, placebo-controlled clinical trial evaluating Dermytol(®) cream for the treatment of actinic keratoses

Purpose

Actinic keratosis lesions (AKs) have the potential to develop into squamous cell carcinoma (SCC) and thus therapies to prevent SCC development from AKs are warranted. The aim of this study was to assess the effects of a 3 month application of a canola phenolic acid-based cream (CPA) on AK lesions.

Patients and methods

This was a randomized, double-blind, placebo-controlled, 12 week clinical study conducted at a single-center in Santo Domingo, Dominican Republic. Forty-five subjects (30 CPA and 15 placebo), aged 45–85 years with 3–10 AKs within a 20 cm² treatment area (scalp, forehead, dorsal forearm, neck, or back of hand) were enrolled. The primary outcome was complete or partial lesion clearance and the secondary outcome was safety of CPA.

Results

Although complete AK lesion clearance was not seen in this study, a significant reduction in the mean change from baseline in the average lesion area was observed at weeks 3 (P=0.002), 6 (P<0.001), and 12 (P<0.001) in the CPA group, but only at weeks 6 and 12 in the placebo group (P=0.005 and P=0.002, respectively). Furthermore, the proportion of participants with a $10% decrease in average lesion area was significantly higher in the CPA group than the placebo group at weeks 3 (P=0.05) and 6 (P=0.02), and showed a trend at week 12 (P=0.06). A subset analysis of the change in average lesion area based upon the total lesion area at baseline revealed that CPA elicited a greater reduction than placebo (2×) in participants with a baseline total AK lesion area of 100–500 mm² than in participants with a total area <100 mm² (1.3×).

Conclusion

The results of this study and previous in vitro studies suggest a potential role for CPA in the treatment of AK lesions and the prevention of SCC development.

Sequential treatment of multiple actinic keratoses with solaraze and actikerall

Interest is increasing in the use of sequential or combined therapeutic modalities for spot or area treatment of actinic keratoses (AKs) to achieve complete sustained remission. For multiple lesions in a contained area, topical treatment offers less discomfort, better cosmesis and greater patient convenience than destructive/ablative techniques. Twelve patients with multiple grade I and II AK lesions of the scalp (cases 1–10) or the dorsum of the hand (cases 11 and 12), most with a history of recurrence, were treated with Solaraze gel (3% diclofenac sodium in 2.5% hyaluronic acid) twice daily for 12 weeks, followed by a 2-week treatment-free interval, then Actikerall cutaneous solution (5-fluorouracil 5 mg/g and salicylic acid 100 mg/g) once daily for up to 6 weeks as required. Sequential treatment provided complete (clinical and histological) clearance in 8/10 male patients. Two patients with numerous lesions had partial clearance (significant improvement) and the remaining few lesions were treated with erbium laser. Both female patients achieved complete clinical clearance with sequential treatment. Solaraze/Actikerall were well tolerated. A case of contact dermatitis with Solaraze resolved after discontinuation and the patient progressed to treatment with Actikerall. Local application site reactions resolved upon treatment completion. Topical lesion-directed sequential treatment with Solaraze/Actikerall is a rational approach to treat patients with multiple AKs. Sequential treatment produces excellent clearance rates which are accompanied by relevant improvement in patients’ quality of life.

Topical pharmacotherapy for skin cancer: part II. Clinical applications

The purpose of the paper is to provide an in-depth, evidence-based analysis of the clinical use of topical treatments for skin cancer. A comprehensive review of topical drugs has been performed, including 5-fluorouracil, imiquimod, diclofenac, ingenol mebutate, retinoids, resiquimod, piroxicam, dobesilate, and betulinic acid. The evaluated studies were rated according to their level of evidence level (I-V), as indicated by recent guidelines for evidence-based medicine, The Oxford 2011 Levels of Evidence. Therapeutic response is generally related to tumor type, extent, and localization, and also to patient compliance. Careful patient selection is required in order to achieve the desired goal of complete tumor clearance.