European consensus-based interdisciplinary guideline for diagnosis, treatment and prevention of actinic keratoses, epithelial UV-induced dysplasia and field cancerization on behalf of European Association of Dermato-Oncology, European Dermatology Forum, European Academy of Dermatology and Venereology and Union of Medical Specialists (Union Européenne des Médecins Spécialistes)

A collaboration of multidisciplinary experts from the European Association of Dermato-Oncology, the European Dermatology Forum, the European Academy of Dermatology and Venereology, and the European Union of Medical Specialists was formed to develop European recommendations on AK diagnosis and treatment, based on current literature and expert consensus. This guideline addresses the epidemiology, diagnostics, risk stratification and treatments in immunocompetent as well as immunosuppressed patients. Actinic keratoses (AK) are potential precursors of cutaneous squamous cell carcinoma (cSCC) and display typical histopathologic and immunohistochemical features of this malignancy in an early stage. They can develop into cSSC in situ and become invasive in a low percentage of cases. AK is the most frequent neoplasia in white populations, frequently occurring within a cancerous field induced by ultraviolet radiation. Since it cannot be predicted, which lesion will progress to cSCC and when treatment is usually recommended. The diagnosis of AK and field cancerization is made by clinical examination. Dermatoscopy, confocal microscopy, optical coherence tomography or line-field confocal-OCT can help in the differential diagnosis of AK and other skin neoplasms. A biopsy is indicated in clinically and/or dermatoscopically suspicious and/or treatment-refractory lesions. The choice of treatment depends on patients' and lesion characteristics. For single non-hyperkeratotic lesions, the treatment can be started upon patient's request with destructive treatments or topical treatments. For multiple lesions, field cancerization treatment is advised with topical treatments and photodynamic therapy. Preventive measures such as sun protection, self-examination and repeated field cancerization treatments of previously affected skin areas in high-risk patients are advised.

Diagnosis and therapy of actinic keratosis

Actinic keratosis (AK) is considered a chronic and recurring in situ skin neoplasia, with a possible transformation into invasive squamous cell carcinoma (SCC). Among others, predominant risk factors for development of AK are UV-light exposure and immunosuppression. Basal epidermal keratinocyte atypia (AK I) and proliferation (PRO score) seem to drive malignant transformation, rather than clinical appearance of AK (Olsen I-III). Due to the invasiveness of punch biopsy, those histological criteria are not regularly assessed. Non-invasive imaging techniques, such as optical coherence tomography (OCT), reflectance confocal microscopy (RCM) and line-field confocal OCT (LC-OCT) are helpful to distinguish complex cases of AK, Bowen's disease, and SCC. Moreover, LC-OCT can visualize the epidermis and the papillary dermis at cellular resolution, allowing real-time PRO score assessment. The decision-making for implementation of therapy is still based on clinical risk factors, ranging from lesion- to field-targeted and ablative to non-ablative regimens, but in approximately 85% of the cases a recurrence of AK can be observed after a 1-year follow-up. The possible beneficial use of imaging techniques for a non-invasive follow-up of AK to detect recurrence or invasive progression early on should be subject to critical evaluation in further studies.

Diagnose und Therapie aktinischer Keratosen

Actinic keratosis (AK) is considered a chronic and recurring in situ skin neoplasia, with a possible transformation into invasive squamous cell carcinoma (SCC). Among others, predominant risk factors for development of AK are UV-light exposure and immunosuppression. Basal epidermal keratinocyte atypia (AK I) and proliferation (PRO Score) seem to drive malignant turnover, rather than clinical appearance of AK (Olsen I-III). Due to the invasiveness of punch biopsy, those histological criteria are not regularly assessed. Non-invasive imaging techniques, such as optical coherence tomography (OCT), reflectance confocal microscopy (RCM) and line-field confocal OCT (LC-OCT) are helpful to distinguish complex cases of AK, Bowen's disease and SCC. Moreover, LC-OCT can visualize the epidermis and the papillary dermis at cellular resolution, allowing real-time PRO Score assessment. The decision-making for implementation of therapy is still based on clinical risk factors, ranging from lesion- to field-targeted and ablative to non-ablative regimes, but in approximately 85% of the cases a recurrence of AK can be observed after a 1-year follow-up. The possible beneficial use of imaging techniques for a non-invasive follow-up of AK to detect recurrence or invasive progression early on should be subject to critical evaluation in further studies.

Digitally Enhanced Methods for the Diagnosis and Monitoring of Treatment Responses in Actinic Keratoses: A New Avenue in Personalized Skin Care

Non-melanocytic skin cancers represent an important public health problem due to the increasing incidence and the important local destructive potential. Thus, the early diagnosis and treatment of precancerous lesions (actinic keratoses) is a priority for the dermatologist. In recent years, non-invasive skin imaging methods have seen an important development, moving from simple observational methods used in clinical research, to true diagnostic and treatment methods that make the dermatologist's life easier. Given the frequency of these precancerous lesions, their location on photo-exposed areas, as well as the long treatment periods, with variable, imprecise end-points, the need to use non-invasive imaging devices is increasingly evident to complete the clinical observations in the diagnosis and treatment of these lesions, with the aim of increasing accuracy and decreasing the adverse effects due to long treatment duration. This is the first review that brings together all skin imaging methods (dermoscopy, reflectance confocal microscopy, ultrasonography, dermoscopy-guided high frequency ultrasonography, and optical coherence tomography) used in the evaluation of actinic keratoses and their response to different treatment regimens.

Skin field cancerisation: A systematic review of the literature regarding its treatment

INTRODUCTION

Skin neoplasms are the most frequent malignant lesions, increasing patient's morbidity when associated with skin field cancerisation. There is a need to understand the current therapies, both clinical and surgical.

METHODS

A systematic review was performed according to the PRISMA guideline, registered in PROSPERO: CRD42018114826, including studies from 2012 to 2019.

RESULTS

Seven hundred and eighty-two studies were found, of which 21 were included. Of these, 8 primary studies were randomised controlled trials: fractional CO₂ laser-assisted photodynamic therapy (PDT) vs. PDT (no significance), daylight PDT vs. PDT (no significance, daylight PDT had less adverse effects), trichloroacetic acid peel vs. 5-aminolaevulinic acid PDT (clinical improvement of aminolaevulinic acid PDT), 5-Fluorouracil 0.5%/Salicylic Acid 10% vs. vehicle (clinical improvement of 5-Fluorouracil 0.5%/Salicylic Acid 10%), photolyase vs. sun filters (no significance), sunscreens vs. sunscreens plus DNA repair enzymes (DNA Repair Enzymes was more effective in reducing field cancerisation). Only one systematic review was included in which there was effectiveness of daylight PDT in the treatment of actinic keratoses. The other 12 included studies had a lower level of evidence including surgical studies.

CONCLUSION

Clinical studies are more relevant in the treatment of the field cancerisation. There is a lack of surgical studies.

Treatment monitoring of 5-fluorouracil 0.5%/salicylic acid 10% lesion-directed therapy for actinic keratosis using dermoscopy and in-vivo reflectance confocal microscopy

Recently, 5-fluorouracil 0.5%/salicylic acid 10% (5-FU/SA) topical solution has been included in the National Italian portfolio for lesion-directed treatment of grade I/II actinic keratosis (AKs) located on the face or scalp. To describe the utility of dermoscopy and RCM in treatment response monitoring of a series of AKs treated with 5-FU/SA as lesion-directed therapy. Consecutive patients were prospectively treated for a maximum of 12 weeks with 5-FU/SA for AKs located on the face or scalp. Clinical, dermoscopic, and confocal images of one index AK were acquired at each visit and pre-specified criteria were evaluated. Clinical, dermoscopic, and confocal responses were evaluated at last follow-up visit. Fourteen patients were enrolled, of which five were treated for 12 weeks, seven for 8, and two for 4 weeks. At a median follow up of 30 weeks, 64.3% (9/14) index AKs achieved complete clinical, 50% (7/14) complete dermoscopic and 42.9% (6/14) complete confocal clearance. Local skin reaction was mild and significantly decreased during therapy administration. Although the small number of cases, our study underlines the utility of both dermoscopy and in-vivo RCM in 5-FU/SA treatment response monitoring for AKs located on the face or scalp.

Effects of topical piroxicam and sun filters in actinic keratosis evolution and field cancerization: a two-center, assessor-blinded, clinical, confocal microscopy and dermoscopy evaluation trial

Background: Actinic keratosis (AK) is considered an "in situ" non-melanoma skin cancer induced by ultraviolet chronic exposure. Sunscreen and topical anti-inflammatory agents like diclofenac could improve the evolution of this kind of lesions. A topical product containing piroxicam 0.8% and sun filters (50 SPF) (ACTX) has been shown to be very effective in reducing AK lesions. So far, no data are available regarding the effects of this product on skin modifications evaluated by reflectance confocal microscopy (RCM) and dermoscopy at the lesion sites and on the skin around the lesions (field cancerization). Study aim: To evaluate in a two-center, assessor-blinded, prospective trial the effect of ACTX on AK number, RCM and dermoscopy parameter evolution of a target lesion in subjects with multiple AK lesions. Subjects and methods: A total of 54 subjects (42 men and 12 women; mean age 65 years) with AK lesions grade I-III located on the scalp (n = 36) or face (n = 18) were enrolled after their written informed consent. ACTX was applied twice daily on the face and scalp for six consecutive months. AK lesion count was performed at baseline and after 3 and 6 months. Lesion count was assessed in a blind fashion evaluating digital color high definition images performed at each visit and coded in a blinded fashion. RCM evaluations were performed at the same time-points. A dermoscopy evaluation was performed at baseline and after 6 months. RCM and dermoscopy were assessed on a pre-specified target lesion. The RCM severity score was used evaluating 11 items, examining stratum corneum, stratum granulosum, stratum spinous and dermal layers (maximum score 11 points). The dermoscopy score evaluated erythema, scaling and follicular plugs (from 0 to 4 for each item) and pigmentation (from 0 to 5). Results: Forty-nine subjects (90%) concluded the trial. At baseline, the mean (SD) number of AK lesions was 9.6 (5.2). AK lesions significantly decreased to 5.9 and to 5.6 after 3 and 6 months of ACTX treatment (p = .001; intention to treat analysis), representing a -42% reduction. A reduction of AK lesion numbers >50% in comparison with baseline was observed in 51% of subjects at month 6. New AK lesions appeared in five subjects (9%). The RCM mean (SD) severity score at baseline was 6.4 (2.0). ACTX treatment was associated with a progressive and significant (p = .002) reduction to 4.9 after 3 months and to 4.8 (2.3) at month 6 (a -25% reduction). The dermoscopy score at baseline was 5.5 (2) and it was reduced significantly (p = .007) to 4.5 (2) at the end of the study. The product was in general very well tolerated. Conclusion: A 6 month application of ACTX in subjects with AK lesions was associated with an improvement in AK lesion count and with a reduction in the RCM/dermoscopy severity scores of the target lesion. Trial registration number: ISRCTN22070974.

Management of clinical and subclinical actinic keratoses with histological and immunohistochemical assessments by confocal microscopy

Reflectance confocal microscopy has been used to monitor treatment efficacy in non-melanoma skin cancer, but few studies have compared different therapies using the same confocal criteria. We compare a single score designed in previous study to evaluate confocal, histological, and immunohistochemical results obtained before and after two treatments of actinic keratosis (AK) and in field cancerisation area. Thirty volunteer male patients, aged >50-year old, with at least three clinically visible AKs on the bald scalp, were included in this study: 15 patients were submitted to 3% diclofenac therapy and 15 to 5% fluorouracil therapy. Confocal imaging was performed on a 5 × 5 cm skin area. In five patients of each group we performed cutaneous biopsies. Scaling, upper nucleated cells, and inflammatory cells showed a higher percentage reduction in field cancerisation, especially in diclofenac treatment group, while in AK inflammatory cells showed a greater percentage reduction in 5-fluorouracil treatment group. Both therapies are efficacious, but their effectiveness is different on the single parameters of the confocal, histology, immunohistochemically.

Defining the actinic keratosis field: a literature review and discussion

Despite the chronic and increasingly prevalent nature of actinic keratosis (AK) and existing evidence supporting assessment of the entire cancerization field during clinical management, a standardized definition of the AK field to aid in the understanding and characterization of the disease is lacking. The objective of this review was to present and appraise the available evidence describing the AK cancerization field, with the aim of determining a precise definition of the AK field in terms of its molecular (including genetic and immunological), histological and clinical characteristics. Eight European dermatologists collaborated to conduct a review and expert appraisal of articles detailing the characteristics of the AK field. Articles published in English before August 2016 were identified using PubMed and independently selected for further assessment according to predefined preliminary inclusion and exclusion criteria. In addition, a retrospective audit of patients with AK was performed to define the AK field in clinical terms. A total of 32 review articles and 47 original research articles provided evidence of sun-induced molecular (including genetic and immunological) and histological skin changes in the sun-exposed area affected by AK. However, the available literature was deemed insufficient to inform a clinical definition of the AK field. During the retrospective audit, visible signs of sun damage in 40 patients with AK were assessed. Telangiectasia, atrophy and pigmentation disorders emerged as 'reliable or very reliable' indicators of AK field based on expert opinion, whereas 'sand paper' was deemed a 'moderately reliable' indicator. This literature review has revealed a significant gap of evidence to inform a clinical definition of the AK field. Therefore, the authors instead propose a clinical definition of field cancerization based on the identification of visible signs of sun damage that are reliable indicators of field cancerization based on expert opinion.

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.

The Role of Reflectance Confocal Microscopy in Clinical Trials for Tumor Monitoring

Reflectance confocal microscopy (RCM) allows the evaluation with superb accuracy of some skin tumors before, during, and after treatment. In clinical trials RCM has been shown to provide useful information for evaluation of efficacy of topical or systemic medication. With the recent introduction of handheld RCM a fast examination of the tumor can be done in minutes. In patients treated with surgery RCM plays a unique role to precisely map margins of the tumor in the skin surface and for the detection of subclinical recurrences. This article reviews the use of RCM in the research of different skin cancer tumor treatments.

Efficacy and Safety of 5-Fluorouracil 0.5%/Salicylic Acid 10% in the Field-Directed Treatment of Actinic Keratosis: A Phase III, Randomized, Double-Blind, Vehicle-Controlled Trial

Introduction

Due to the high prevalence of actinic keratosis (AK) and potential for lesions to become cancerous, clinical guidelines recommend that all are treated. The objective of this study was to evaluate the efficacy and safety of 5-fluorouracil (5-FU) 0.5%/salicylic acid 10% as field-directed treatment of AK lesions.

Methods

This multicenter, double-blind, vehicle-controlled study (NCT02289768) randomized adults, with a 25 cm² area of skin on their face, bald scalp, or forehead covering 4–10 clinically confirmed AK lesions (grade I/II), 2:1 to treatment or vehicle applied topically once daily for 12 weeks. The primary endpoint was the proportion of patients with complete clinical clearance (CCC) of lesions in the treatment field 8 weeks after the end of treatment. Secondary endpoints included partial clearance (PC; ≥75% reduction) of lesions. Safety outcomes were assessed.

Results

Of 166 patients randomized, 111 received 5-FU 0.5%/salicylic acid 10% and 55 received vehicle. At 8 weeks after the end of treatment, CCC was significantly higher with 5-FU 0.5%/salicylic acid 10% than with vehicle [49.5% vs. 18.2%, respectively; odds ratio (OR) 3.9 (95% CI) 1.7, 8.7; P = 0.0006]. Significantly more patients achieved PC of lesions with treatment than with vehicle [69.5% vs. 34.6%, respectively; OR 4.9 (95% CI 2.3, 10.5); P < 0.0001]. Treatment-emergent adverse events, predominantly related to application- and administration-site reactions, were more common with 5-FU 0.5%/salicylic acid 10% than with vehicle (99.1% vs. 83.6%).

Conclusions

Compared with vehicle, field-directed treatment of AK lesions with 5-FU 0.5%/salicylic acid 10% was effective in terms of CCC. Safety outcomes were consistent with the known and predictable safety profile.

Trial registration

NCT02289768.

Funding

Almirall S.A.

Electronic supplementary material

The online version of this article (doi:10.1007/s13555-016-0161-2) contains supplementary material, which is available to authorized users.

Low-dose 5-fluorouracil in combination with salicylic acid for the treatment of actinic keratoses on the hands and/or forearms - results of a non-interventional study

BACKGROUND

As an in situ carcinoma, actinic keratoses should be treated early. Previous studies on the efficacy of a low-dose 0.5% 5-fluorouracil solution in combination with 10% salicylic acid (low-dose 5-FU/SA) are mostly related to lesions appearing on the head and face. In contrast, actinic keratoses (AK) lesions of the upper extremities are considered to be difficult to treat.

OBJECTIVE

The efficacy of low-dose 5-FU/SA in the treatment of actinic keratoses on the hands and/or forearms was studied for the first time in this non-interventional study (NIS) under practical conditions in a large patient population. In addition to the clinical course during therapy and a follow-up period, the length of application and adherence were documented.

METHODS

As part of this NIS, 649 patients with AK were treated at 207 centres with low-dose 5-FU/SA. The data of the study were recorded at baseline, optionally during an intermediate examination, at the end of therapy and during a final assessment.

RESULTS

The average number of AK lesions decreased during the entire observation period by 92%. Side-effects were documented only rarely in the form of local skin reactions (2%). The attending physicians assessed the efficacy, tolerability and safety of the therapy as being predominantly very good or good (in each case ≥90%).

CONCLUSION

AK lesions on the hands and/or forearms were effectively treated with low-dose 5-FU/SA under routine conditions in dermatological practice and the treatment was well tolerated.

Use of Polyphenolic Compounds in Dermatologic Oncology

Polyphenols are a widely used class of compounds in dermatology. While phenol itself, the most basic member of the phenol family, is chemically synthesized, most polyphenolic compounds are found in plants and form part of their defense mechanism against decomposition. Polyphenolic compounds, which include phenolic acids, flavonoids, stilbenes, and lignans, play an integral role in preventing the attack on plants by bacteria and fungi, as well as serving as cross-links in plant polymers. There is also mounting evidence that polyphenolic compounds play an important role in human health as well. One of the most important benefits, which puts them in the spotlight of current studies, is their antitumor profile. Some of these polyphenolic compounds have already presented promising results in either in vitro or in vivo studies for non-melanoma skin cancer and melanoma. These compounds act on several biomolecular pathways including cell division cycle arrest, autophagy, and apoptosis. Indeed, such natural compounds may be of potential for both preventive and therapeutic fields of cancer. This review evaluates the existing scientific literature in order to provide support for new research opportunities using polyphenolic compounds in oncodermatology.

Low-Dose 0.5% 5-Fluorouracil/10% Salicylic Acid Topical Solution in the Treatment of Actinic Keratoses

Background:

Actinic keratosis (AK) lesions have the potential to develop into invasive squamous cell carcinomas (SCCs), and approaches to treatment are evolving to try to reduce the burden of SCC.

Objective:

To present the published clinical research surrounding the use of 0.5% 5-fluorouracil with 10% salicylic acid (low-dose 5-FU/SA) for the treatment of hyperkeratotic AKs.

Method:

A review of published clinical evidence for low-dose 5-FU/SA for the treatment of AKs. The articles were selected following a MEDLINE database search of the combined terms fluorouracil, salicylic acid and actinic keratosis which represent the peer review publications of clinical studies that primarily investigate the use of Actikerall in AK.

Results:

Combining low-dose 5-FU with keratolytic SA is associated with high rates of histologic clearance, reduction in lesion number/area, and sustained clinical response in clinical study and the clinical practice setting. Low-dose 5-FU/SA has also been evaluated using imaging to detect the progression of subclinical AK lesions through a course of the field-directed treatment.

Conclusion:

Low-dose 5-FU/SA is an effective and well-tolerated treatment option licensed for the lesion-directed treatment of mild-to-moderate hyperkeratotic AK lesions.