Comparison of the efficacy and tolerability of 3% diclofenac sodium gel and 5% imiquimod cream in the treatment of actinic keratosis

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.

Comparative Efficacy and Safety of Tirbanibulin for Actinic Keratosis of the Face and Scalp in Europe: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

Actinic keratosis (AK) is a chronic skin condition that may progress to cutaneous squamous cell carcinoma. We conducted a systematic review of efficacy and safety for key treatments for AK of the face and scalp, including the novel 5-day tirbanibulin 1% ointment. MEDLINE, PubMed, Embase, Cochrane Library, clinical trial registries and regulatory body websites were searched. The review included 46 studies, of which 35 studies included interventions commonly used in Europe and were sufficiently homogenous to inform a Bayesian network meta-analysis of complete clearance against topical placebo or vehicle. The network meta-analysis revealed the following odds ratios and 95% credible intervals: cryosurgery 13.4 (6.2-30.3); diclofenac 3% 2.9 (1.9-4.3); fluorouracil 0.5% + salicylic acid 7.6 (4.6-13.5); fluorouracil 4% 30.3 (9.1-144.7); fluorouracil 5% 35.0 (10.2-164.4); imiquimod 3.75% 8.5 (3.5-22.4); imiquimod 5% 17.9 (9.1-36.6); ingenol mebutate 0.015% 12.5 (8.1-19.9); photodynamic therapy with aminolevulinic acid 24.1 (10.9-52.8); photodynamic therapy with methyl aminolevulinate 11.7 (6.0-21.9); tirbanibulin 1% 11.1 (6.2-20.9). Four sensitivity analyses, from studies assessing efficacy after one treatment cycle only, for ≤25 cm2 treatment area, after 8 weeks post-treatment, and with single placebo/vehicle node confirmed the findings from the base case. Safety outcomes were assessed qualitatively. These results suggest that tirbanibulin 1% offers a novel treatment for AK, with a single short treatment period, favourable safety profile and efficacy, in line with existing topical treatments available in Europe.

Guidelines of care for the management of actinic keratosis

BACKGROUND

Actinic keratoses (AK) are rough scaly patches that arise on chronically ultraviolet-exposed skin and can progress to keratinocyte carcinoma.

OBJECTIVE

This analysis examined the literature related to the management of AK to provide evidence-based recommendations for treatment. Grading, histologic classification, natural history, risk of progression, and dermatologic surveillance of AKs are also discussed.

METHODS

A multidisciplinary Work Group conducted a systematic review to address 5 clinical questions on the management of AKs and applied the Grading of Recommendations, Assessment, Development, and Evaluation approach for assessing the certainty of the evidence and formulating and grading clinical recommendations. Graded recommendations were voted on to achieve consensus.

RESULTS

Analysis of the evidence resulted in 18 recommendations.

LIMITATIONS

This analysis is based on the best available evidence at the time it was conducted. The pragmatic decision to limit the literature review to English language randomized trials may have excluded data published in other languages or limited identification of relevant long-term follow-up data.

CONCLUSIONS

Strong recommendations are made for using ultraviolet protection, topical imiquimod, topical 5-fluorouracil, and cryosurgery. Conditional recommendations are made for the use of photodynamic therapy and diclofenac for the treatment of AK, both individually and as part of combination therapy regimens.

A Systematic Review and Meta-Analysis of Interventions for Actinic Keratosis from Post-Marketing Surveillance Trials

Multiple interventions are available for the treatment of actinic keratosis (AK) showing high efficacy in pivotal trials. However, data from post-marketing surveillance studies have received little attention until now. Here, we systematically investigate interventions for AK from post-marketing surveillance trials as a proxy for real-world efficacy and tolerability. A systematic literature search was conducted in Medline, Embase, and CENTRAL. Pertinent trial registers were hand-searched until 25 March 2020. Results were pooled using a random-effects model to calculate pooled proportions and relative risks (RR) or were described qualitatively. Eleven records with a total sample size of n = 4109 were included. Three of the studies had an active-controlled design, while seven were single-armed. Participant complete clearance ranged from 23.1% for diclofenac sodium 3% gel to 88.9% for ingenol mebutate 0.05% gel. The lesion-specific clearance rate for photodynamic therapy (PDT) was 74% (95% confidence interval (CI) 56–87%). The recurrence rate was significantly higher for diclofenac sodium 3% in comparison to imiquimod 5% cream (RR 1.10, 95% CI 1.02–1.1.8) and ranged from 10.6% for ingenol mebutate 0.015% gel to 23.5% for PDT. Few patients discontinued the trials due to adverse events. The results from the majority of the post-marketing surveillance studies deviated from those of pivotal trials.

Actinic Keratosis and Cutaneous Squamous Cell Carcinoma

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) and its precursors, actinic keratoses (AK), are common. Physicians of multiple specialties are confronted with their treatment.

METHODS

This review is based on publications retrieved by a selective search in PubMed, as well as on the German guidelines on AK and cSCC, skin cancer prevention, and surgery with histologic guidance.

RESULTS

Local treatments for AK include lesional cryotherapy, curettage, and laser ablation as well as field-directed treatments with topical agents, e.g., diclofenac plus hyaluronic acid, imiquimod, 5-fluorouracil, ingenol mebutate, and photodynamic therapy. These treatments can be administered in various sequences or combinations, depending on individual factors and the stage of the disease. The gold standard of treatment for cSCC is histologically confirmed complete resection; radiotherapy is an alternative. Locally uncontrollable or metastatic disease is treated with systemic drugs. The use of various chemotherapeutic agents, EGFR-directed therapies, and the PD-I inhibitor cemiplimab, either singly or in combination, has been described in uncontrolled trials and case series. Cemiplimab has a reported response rate of 47% and was recently approved for the treatment of advanced cSCC.

CONCLUSION

There are many options for the treatment of AK and cSCC that must be considered in the interdisciplinary care of these entities.

Long-term clinical outcomes of imiquimod 5% cream vs. diclofenac 3% gel for actinic keratosis on the face or scalp: a pooled analysis of two randomized controlled trials

BACKGROUND

Actinic keratosis (AK) is an early in situ epidermal cancer which can progress to invasive squamous cell carcinoma (SCC). Imiquimod 5% cream (IMIQ) and diclofenac 3% gel (DIC) are frequently used to treat AK; however, their long-term effects following repeated treatment cycles have never been compared.

OBJECTIVE

To compare IMIQ and DIC in the treatment of AK with respect to the risk of change to grade III AK or invasive SCC, after 3 years.

METHODS

Data were pooled from two randomized, active-controlled, open-label, multicentre, multinational, phase IV studies (Clinicaltrials.gov NCT00777127/NCT01453179), with two parallel groups. Studies were conducted between 2008 and 2015 and were almost identical in design. Patients eligible for inclusion were immunocompetent adults with 5-10 visible AK lesions on the face/scalp and grade I/II AK. The primary endpoint was inhibition of histological change to grade III AK or invasive SCC in the study treatment area, observed until month 36. Patients applied either IMIQ or DIC for a maximum of six treatment cycles.

RESULTS

In total, 479 patients (IMIQ 242; DIC 237) were included in the full analysis set. Histological change to grade III AK or invasive SCC was observed until month 36 in 13 (5.4%) patients treated with IMIQ, compared with 26 (11.0%) patients treated with DIC (absolute risk difference -5.6% [95% confidence interval -10.7%, -0.7%]). Time to histological change was greater in the IMIQ group than the DIC group (P = 0.0266). Frequency of progression to invasive SCC was lower with IMIQ than with DIC at all time points. Initial clearance rate was higher in the IMIQ group compared with the DIC group, while recurrence rate was lower. Both treatments were well tolerated.

CONCLUSIONS

Over 3 years, IMIQ was superior to DIC in clearing AK lesions and preventing histological change to grade III AK or invasive SCC and recurrence.

Treatment of actinic keratosis through inhibition of cyclooxygenase-2: Potential mechanism of action of diclofenac sodium 3% in hyaluronic acid 2.5

Cyclooxygenase‐2 (COX‐2) and its metabolic product prostaglandin E₂ (PGE₂) are induced in response to growth factors, inflammatory cytokines, tumor promoters, activated oncogenes, and, in the skin, ultraviolet (UV) radiation. Accumulating evidence suggests a role for the COX‐2/PGE₂ pathway in tumorigenesis in various tissue types including cutaneous squamous cell carcinoma. There is also strong evidence for a role in the development of actinic keratoses (AKs) — common dysplastic lesions of the skin associated with UV radiation overexposure — considered as part of a continuum with skin cancer. Non‐steroidal anti‐inflammatory drugs (NSAIDs) exert their anti‐inflammatory, analgesic, and antipyretic effects by reversibly or irreversibly acetylating COX isoforms, inhibiting downstream prostaglandins, and may have a chemopreventive role in malignancies, including skin cancer. Topical treatment of AK lesions with the NSAID diclofenac sodium 3% in combination with hyaluronic acid 2.5% has been shown to be effective and well tolerated, although the mechanism of action remains to be elucidated.

Topical kinase inhibitors induce regression of cutaneous squamous cell carcinoma

Actinic keratoses (AKs) and squamous cell carcinoma in situ (SCCIS) are precursor lesions for cutaneous squamous cell carcinoma (cSCC), the second most common form of cancer. Current topical therapies for AKs and SCCIS promote skin inflammation to eradicate lesions and do not directly target the biological mechanisms driving growth. We hypothesized that topical small molecule inhibitors targeting kinases promoting keratinocyte growth in AKs and SCCIS could induce regression of these lesions with less inflammation. To test this hypothesis, we determined the efficacy of topical dasatinib, 5-fluorouracil and BEZ-235 in inducing regression of cSCCs in the K14-Fyn Y528 transgenic mouse model. Topical dasatinib induced regression of cSCC with less inflammation, no ulceration and no mortality compared to 5-fluorouracil. Topical BEZ-235 induced cSCC regression similar to dasatinib without erythema or ulceration. These data indicate that topical small molecule kinase inhibitors targeting drivers of AK/SCCIS/cSCC growth represent a promising therapeutic approach to treat these common skin lesions.

Actinic keratosis and imiquimod: a review of novel carriers and patents

INTRODUCTION

Actinic keratosis is one of the most common disorder characterized by erythematic and generally attached scaly lesions which are present either alone or in clusters. World Health Organization defines actinic keratosis as a common intraepidermal neoplasm of sun-damaged skin, characterized by variable atypia of keratinocytes.

AREAS COVERED

At the beginning of the 20th century, a new immunomodulator molecule, imiquimod, appears in the market for the treatment of actinic keratosis but suffers from the pitfalls of the conventional approach of dosage form preparation including high dose, poor stability and more side effects. The present article attempts to compile the scatter information related to actinic keratosis and imiquimod at one place. The special emphasis will be made on the information available in various research articles and patents with respect to the efforts made for overcoming shortcomings associated with imiquimod by novel drug delivery or other approaches.

EXPERT OPINION

The conventional drug delivery systems are unsuccessful to improve the actinic keratosis. The patient acceptance and compliance with these treatments are generally poor due to associated side effects, poor cosmetic outcomes and high costs. Therefore, several available and reported novel therapeutic approaches are being developed in order to provide better action.

Astragalin Attenuates UVB Radiation-induced Actinic Keratosis Formation

BACKGROUND

Actinic Keratosis (AK), is the most common precancerous skin lesion induced by the excessive Ultraviolet B (UVB) and is a significant threat to the public health. UVB exposure causes oxidative DNA damage and is considered to be a significant contributor to AK and subsequent development of skin cancer. Besides, activation of p38 MAPK also plays a significant role in the development of AK.

OBJECTIVE

This study aimed at the development of a nature compound which can inhibit UVB-induced AK.

METHOD

MTS Cell Proliferation Assay Kit was used to detect the toxicity of astragalin. HE-staining, Immunohistochemical, Western blot and Enzyme Linked Immunosorbent Assay were applied to examine the clinicopathologic feature of AK and the change of p38 MAPK signal pathway treated with astraglin under the condition of UVB in vitro and in vivo. Results：In our clinical findings revealed that p38 MAPK, phospho-MSK1, and γ -H2AX were significantly highly expressed in human AK tissue than the normal healthy skin tissue. Moreover, in vitro studies showed that UVB induced the phospho-MSK1 and γ-H2AX in a time- and dose-dependent manner in HaCaT cells. Further, in vitro kinase assay demonstrated that astragalin could directly bind to p38 MAPK and suppress p38 MAPK activity. Furthermore, astragalin exhibited no toxicity and suppressed the UVB-induced expression of phospho- MSK1 and γ -H2AX by suppressing p38 MAPK activity in a time-dependent and dose-dependent manner in HaCaT cells. The in vivo studies with animal UV model demonstrated that astragalin inhibited UVB-induced expression of phospho-MSK1 and γ-H2AX in Babl/c mice.

CONCLUSION

These results suggested that p38 MAPK is a direct valid molecular target of astragalin for the attenuation of UVB-induced AK. Furthermore, astragalin could be a potential promising novel natural therapeutic agent for the prevention and management of UVB-induced AK with high target specificity and low toxicity.

Diclofenac sodium gel therapy as an alternative to actinic cheilitis

OBJECTIVE

Actinic cheilitis (AC) is a potentially malignant lesion caused by prolonged exposure to ultraviolet light. The aim of this research was to analyze the efficacy of diclofenac sodium 3% gel in the treatment of this condition, through clinical follow-up.

METHODS

Thirty-one patients diagnosed with AC were instructed to perform a topical application of the gel three times a day for a period of 90 days. In each visit, a digital photography was obtained for verified progress and response to treatment. Two researchers evaluated all images after treatment was completed and assigned the following scores regarding clinical aspect of the lip: 1, complete improvement; 2, partial improvement; 3, no changes; 4, worsening of the clinical condition. In addition, the patients' tolerability to the drug and their satisfaction after treatment were evaluated.

RESULTS

Twelve cases abandoned the treatment for reasons unrelated to the study. Ten participants showed total remission of all clinical features of the lesion and three had partial improvement of the characteristics. One participant presented worsening of clinical condition, and in five cases, treatment was discontinued due to development of mild adverse effects at the site of gel application. Regarding satisfaction analyses and tolerability to the drug, from 14 patients who completed treatment without adverse effects or complications, most agreed fully that they were satisfied with the therapy (n = 11) and that the drug was not irritating to the mouth (n = 9). Patients are being monitored without clinical signs of recurrence and/or progression of the lesions.

CONCLUSION

Topical application of the drug has provided a convenient and well tolerated in most cases.

CLINICAL RELEVANCE

Diclofenac sodium gel (3%) may be a promising alternative for treatment of actinic cheilitis.

Pharmacoeconomy of drugs used in the treatment of actinic keratoses

Actinic keratosis (AK) represents an emerging issue in the area of skin diseases which undergo high risk for developing squamous cell carcinoma (SCC). Recently, evidence has been accumulated that 3% diclofenac sodium and ingenol mubetate may efficiently counteract the development of progressive AK even if the pharmacoeconomic impact of such a treatment remains poorly defined. With the objective of assessing the efficacy of 3% diclofenac sodium versus ingenol mebutate, a comparative cost-efficacy analysis was performed between both pharmacological treatments. In the present analysis, data of efficacy of clinical studies were combined with information on the quality of life associated with AK lesions based on available literature data. Furthermore, the cost associated with the management of these lesions in Italy has been taken into account. To this purpose, we carried out a literature survey on the clinical and economic data among clinical reports available in Italy based on the assessment of related expenditure of public resources and their relationship with the subsequent health benefits.

Cost-utility of first-line actinic keratosis treatments in Finland

Introduction

Cost–utility assessment of first-line actinic keratosis (AK) treatments for max 25 cm² AK field.

Methods

A probabilistic, 2-year decision tree model was used to assess costs, quality-adjusted life-years (QALY), incremental cost-effectiveness ratio (ICER), cost-effectiveness efficiency frontier, cost-effectiveness acceptability frontier (CEAF), and expected value of perfect information (EVPI) of AK treatments from the Finnish health care payer perspective with 3% discounting per annum. In the model, the first-line AK treatment resulted in complete clearance (CC) or non-CC with or without local skin responses (LSR), or AK recurrence. Non-CC AK was treated with methyl aminolevulinate + photodynamic therapy (MAL + PDT), and AK recurrence was retreated with the previous effective treatment. Costs included primary and secondary health care, outpatient drugs, and LSR management. QALYs were assessed with the EuroQol (EQ-5D-3L). Result robustness was assessed with sensitivity analyses.

Results

The mean simulated per patient QALYs (costs) were 1.526 (€982) for MAL + PDT, 1.524 (€794) for ingenol mebutate gel (IngMeb) 0.015% (3 days), 1.522 (€869) for IngMeb 0.05% (2 days), 1.520 (€1062) for diclofenac 3% (12 weeks), 1.518 (€885) for imiquimod 3.75% (6 weeks), 1.517 (€781) for imiquimod 5% (4/8 weeks), and 1.514 (€1114) for cryosurgery when treating AK affecting any body part. IngMeb 0.015% was less costly and more effective (dominating) than other AK treatments indicated for face and scalp area with the exception of imiquimod 5% for which the ICER was estimated at €1933/QALY gained and MAL + PDT, which had an ICER of €82,607/QALY gained against IngMeb 0.015%. With willingness-to-pay €2526–18,809/QALY gained, IngMeb 0.015% had >50% probability for cost-effectiveness on the CEAF. IngMeb 0.05% dominated AK treatments indicated for trunk and extremities. EVPIs for face and scalp (trunk and extremities) analyses were €26 (€0), €86 (€58), and €250 (€169) per patient with the willingness-to-pay of €0, €15,000, and €30,000 per QALY gained, respectively.

Conclusion

IngMebs were cost-effective AK treatments in Finland.

Funding

LEO Pharma.

Electronic supplementary material

The online version of this article (doi:10.1007/s12325-015-0211-7) contains supplementary material, which is available to authorized users.

Solar keratoses: photodynamic therapy, cryotherapy, 5-fluorouracil, imiquimod, diclofenac, or what? Facts and controversies

Actinic keratosis is a common dermatologic condition that may regress, remain stable, or progress to squamous cell carcinoma. Some question whether all actinic keratoses should be routinely treated, whereas others contend that the unpredictable natural history of this disease necessitates treatment to prevent malignant transformation. Available treatments include photodynamic therapy, cryotherapy, 5-fluorouracil, imiquimod, and diclofenac. Each of these options has its advantages and disadvantages, although they all have a place in the management of actinic keratosis. An overview of these treatment modalities is presented, as are the controversies surrounding the treatment of actinic keratosis.

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.

Comparative study of actinic keratosis treatment with 3% diclofenac sodium and 5% 5-fluorouracil

BACKGROUND

Actinic keratosis is a frequent lesion which occurs in sunlight exposed areas. Diclofenac sodium and 5-Fluorouracil are effective, non-invasive and easy-to-apply topical treatment options.

OBJECTIVES

To assess and compare the effectiveness of 3% diclofenac sodium associated with 2.5% hyaluronic acid and of 5% 5-Fluorouracil for the treatment of actinic keratosis, as well as the patient's degree of satisfaction and tolerability.

METHODS

28 patients with a clinical diagnosis of actinic keratosis were randomized to receive diclofenac sodium or 5-Fluorouracil and were clinically assessed before and after treatment as well as 8 weeks after the end of treatment. Modified versions of the Investigator and Patient Global Improvement Scores were used.

RESULTS

The average number of lesions in the diclofenac sodium group before and after treatment was 13.6 and 6.6 (p<0,001), respectively, while it was 17.4 and 3.15 (p<0.001) in the 5-Fluorouracil group. There was a significant reduction in the number of lesions in the 5-Fluorouracil group in relation to the diclofenac sodium group (p<0.001). To the non-blinded physician, there was a higher satisfactory therapeutic response in the 5-Fluorouracil group (p<0.001); to the blinded physician, there was a higher satisfactory response in this same group, although not statistically significant (p=0.09). There was a high degree of satisfaction in both groups (73% in the diclofenac sodium group and 77% in the 5-Fluorouracil group; p=0.827). Regarding adverse effects, the diclofenac sodium group presented a higher degree of satisfaction (93.3% vs 38.4%; p=0.008). Erythema, edema, crusts and itching were significantly higher in the 5-Fluorouracil group.

CONCLUSION

We concluded that 5-Fluorouracil was more effective; however, it showed lower tolerability than diclofenac sodium.

Actinic keratosis: a clinical and epidemiological revision

Actinic keratoses are benign intraepithelial skin neoplasms constituted by atypical proliferation of keratinocytes that may evolve to squamous cell carcinoma. They develop in photoexposed skin areas; they are induced mainly by ultraviolet radiation and are considered cutaneous markers of chronic exposure to sunlight. They develop mainly in adults and older, fair skinned individuals, and are the fourth most common cause of dermatologic consultation in Brazil. Damage to the apoptosis pathway in photoexposed epithelium favors cellular proliferation and the permanence of the lesions. In this revision, the authors assemble the main epidemiological data regarding this disease and suggest that strategies to identify risky phenotypes, early diagnosis, adequate treatment, clinical follow-up, stimulus to skin self examination, photoeducation and photoprotection should be promoted with the aim of avoiding the progression to malignancy and also the prevention and the diagnose of concomitant neoplasms also induced by ultraviolet radiation.

Clinical, dermoscopic and immunohistochemical assessment of actinic keratoses and evaluation of the effectiveness of diclofenac therapy with immunohistochemical analysis

Actinic keratoses (AKs) is a keratinocytic neoplasm that typically develops on the face of elderly patients. Little is known regarding the clinical, dermatoscopic and immunohistochemical assessments of AK using topical diclofenac therapy. We sought to determine these assessments and evaluate the efficacy of topical diclofenac gel in AK. In this prospective, open-label study, 44 patients with 66 AKs were treated for 12 weeks with topically applied diclofenac (3% gel in 2.5% hyaluronic acid). Immunohistopathologic analyses were performed before and after diclofenac treatment using epidermal stem cell markers such as Cytokeratin 15 (CK15), Cytokeratin 19 (CK19) and p63, in addition to proliferation markers (Bcl-2, Ki-67). Diclofenac gel was found to be effective in AK, including the hyperkeratotic type. Surprisingly, complete remission was observed at a significantly higher rate in Grade 3 lesions (p = 0.017). However, imunohistochemical and histopathologic examinations revealed that 12-week treatment periods may not be sufficient to fully cure AK. The immunohistochemical analyses revealed no change in the expression levels of CK15, CK19 and Bcl-2 following diclofenac therapy. However, the expression of Ki-67 (p = 0.042) and p63 (p = 0.030) exhibited a significant decrease after therapy. Dermatoscopy is an effective method for diagnosis of AK, and topical diclofenac sodium gel was found as an effective additional treatment modality. Since positive histopathological findings were detected in some patients even with significant remission, a 12-week treatment period should be extended even in patients presenting with positive clinical response. Importantly, anti-proliferative effects of diclofenac were demonstrated by decreased Ki-67 and p63 expression levels.

Pharmacotherapy of actinic keratosis: an update

INTRODUCTION

Actinic keratosis (AK) represents the initial intraepidermal manifestation of abnormal keratinocyte proliferation, with the potential of progression to squamous cell carcinoma (SCC). Few visible AKs lead to the use of lesion-directed treatments, including ablative and/or surgical procedures. Multiple and/or the suspicion of subclinical (non-visible) AKs lead to the use of field-directed therapies, including topical and ablative treatments. Predicting which AK will progress to SCC is difficult, and so all are treated. The goals of treatment are to eliminate visible AKs and to treat subclinical (non-visible) AKs, minimizing their risk of progression to invasive SCC, while pursuing good cosmesis.

AREAS COVERED

This review discusses the prevention of AKs (such as ultraviolet light avoidance, sunscreen use, protective clothing, and frequent self-examinations, in addition to chemoprevention with retinoids, eflornithine, silymarin, and others). It also covers lesion-directed treatments (e.g., cryotherapy, electrodessication and curettage, and surgery). Field-directed treatments are also mentioned (including laser resurfacing, dermabrasion, chemical peels, topical immunomodulators (imiquimod and diclofenac), topical chemotherapeutic agents (5-fluorouracil and retinoids), and photodynamic therapy). Finally, newer and investigational treatments are discussed (including ingenol mebutate).

EXPERT OPINION

There is no panacea in the treatment of AKs. The current best approach is the sequential treatment with a lesion-directed and a field-directed therapy. Several combinations seem to work well; they just need to be selected based on the evidence and adjusted to patient needs, preferences and dermatologist expertise.

Interventions for actinic keratoses

BACKGROUND

Actinic keratoses are a skin disease caused by long-term sun exposure, and their lesions have the potential to develop into squamous cell carcinoma. Treatments for actinic keratoses are sought for cosmetic reasons, for the relief of associated symptoms, or for the prevention of skin cancer development. Detectable lesions are often associated with alteration of the surrounding skin (field) where subclinical lesions might be present. The interventions available for the treatment of actinic keratoses include individual lesion-based (e.g. cryotherapy) or field-directed (e.g. topical) treatments. These might vary in terms of efficacy, safety, and cosmetic outcomes.

OBJECTIVES

To assess the effects of topical, oral, mechanical, and chemical interventions for actinic keratosis.

SEARCH METHODS

We searched the following databases up to March 2011: the Cochrane Skin Group Specialised Register, CENTRAL in The Cochrane Library, MEDLINE (from 2005), EMBASE (from 2010), and LILACS (from 1982). We also searched trials registers, conference proceedings, and grey literature sources.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing the treatment of actinic keratoses with either placebo, vehicle, or another active therapy.

DATA COLLECTION AND ANALYSIS

At least two authors independently abstracted data, which included adverse events, and assessed the quality of evidence. We performed meta-analysis to calculate a weighted treatment effect across trials, and we expressed the results as risk ratios (RR) and 95% confidence intervals (CI) for dichotomous outcomes (e.g. participant complete clearance rates), and mean difference (MD) and 95% CI for continuous outcomes (e.g. mean reduction in lesion counts).

MAIN RESULTS

We included 83 RCTs in this review, with a total of 10,036 participants. The RCTs covered 18 topical treatments, 1 oral treatment, 2 mechanical interventions, and 3 chemical interventions, including photodynamic therapy (PDT). Most of the studies lacked descriptions of some methodological details, such as the generation of the randomisation sequence or allocation concealment, and half of the studies had a high risk of reporting bias. Study comparison was difficult because of the multiple parameters used to report efficacy and safety outcomes, as well as statistical limitations. We found no data on the possible reduction of squamous cell carcinoma.The primary outcome 'participant complete clearance' significantly favoured four field-directed treatments compared to vehicle or placebo: 3% diclofenac in 2.5% hyaluronic acid (RR 2.46, 95% CI 1.66 to 3.66; 3 studies with 420 participants), 0.5% 5-fluorouracil (RR 8.86, 95% CI: 3.67 to 21.44; 3 studies with 522 participants), 5% imiquimod (RR 7.70, 95% CI 4.63 to 12.79; 9 studies with1871 participants), and 0.025% to 0.05% ingenol mebutate (RR 4.50, 95% CI 2.61 to 7.74; 2 studies with 456 participants).It also significantly favoured the treatment of individual lesions with photodynamic therapy (PDT) compared to placebo-PDT with the following photosensitisers: aminolevulinic acid (ALA) (blue light: RR 6.22, 95% CI 2.88 to 13.43; 1 study with 243 participants, aminolevulinic acid (ALA) (red light: RR 5.94, 95% CI 3.35 to 10.54; 3 studies with 422 participants), and methyl aminolevulinate (MAL) (red light: RR 4.46, 95% CI 3.17 to 6.28; 5 studies with 482 participants). ALA-PDT was also significantly favoured compared to cryotherapy (RR 1.31, 95% CI 1.05 to 1.64).The corresponding comparative risks in terms of number of participants completely cleared per 1000 were as follows: 313 with 3% diclofenac compared to 127 with 2.5% hyaluronic acid; 136 with 0.5% 5-fluorouracil compared to 15 with placebo; 371 with 5% imiquimod compared to 48 with placebo; 331 with ingenol mebutate compared to 73 with vehicle; 527 to 656 with ALA/MAL-PDT treatment compared to 89 to 147 for placebo-PDT; and 580 with ALA-PDT compared to 443 with cryotherapy.5% 5-fluorouracil efficacy was not compared to placebo, but it was comparable to 5% imiquimod (RR 1.85, 95% Cl 0.41 to 8.33).A significant number of participants withdrew because of adverse events with 144 participants affected out of 1000 taking 3% diclofenac in 2.5% hyaluronic acid, compared to 40 participants affected out of 1000 taking 2.5% hyaluronic acid alone, and 56 participants affected out of 1000 taking 5% imiquimod compared to 21 participants affected out of 1000 taking placebo.Based on investigator and participant evaluation, imiquimod treatment and photodynamic therapy resulted in better cosmetic outcomes than cryotherapy and 5-fluorouracil.

AUTHORS' CONCLUSIONS

For individual lesions, photodynamic therapy appears more effective and has a better cosmetic outcome than cryotherapy. For field-directed treatments, diclofenac, 5-fluorouracil, imiquimod, and ingenol mebutate had similar efficacy, but their associated adverse events and cosmetic outcomes are different. More direct comparisons between these treatments are needed to determine the best therapeutic approach.

Non-ablative fractional resurfacing in combination with topical tretinoin cream as a field treatment modality for multiple actinic keratosis: a pilot study and a review of other field treatment modalities

BACKGROUND

Actinic keratoses (AK) are premalignant lesions occurring mainly in sun-damaged skin. Current topical treatment options for AK and photo-damaged skin such as liquid nitrogen and electrosurgery are not suitable for field treatment. Otherwise, therapies suitable for field treatment bring along considerable patient discomfort. Non-ablative fractional resurfacing has emerged as a logical treatment option especially for field treatment of AK.

OBJECTIVES

To evaluate the clinical efficacy of fractional laser therapy for clearing AK and improving skin quality. To compare patient friendliness of the "fractional" therapy with those reported for other field treatment modalities.

MATERIALS & METHODS

Ten patients with Fitzpatrick skin type I to III with multiple AK and extensive sun-damaged skin, received 5-10 sessions with a 4-week interval using a 1550 nm Erbium-Glass Fractionated laser (Sellas, Korea). Four weeks and 24 weeks after the last treatment the clinical results were evaluated by an independent physician.

RESULTS

The mean degree of improvement, in terms of reduction in the number of AK and improvement of skin texture, was 54% on a 4 point PGA scale, and persisted for approximately 6 months. The biggest advantage of fractional laser treatment, besides the eradication of AK and a clear rejuvenation effect, is the absence of "downtime".

CONCLUSION

Fractional non-ablative resurfacing induces significant reduction in the number of AK and improves the skin quality. Also all patients preferred fractional laser therapy above other AK treatment modalities.

From keratinocyte to cancer: the pathogenesis and modeling of cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (cSCC) is the second most common human cancer with over 250,000 new cases annually in the US and is second in incidence only to basal cell carcinoma. cSCC typically manifests as a spectrum of progressively advanced malignancies, ranging from a precursor actinic keratosis (AK) to squamous cell carcinoma (SCC) in situ (SCCIS), invasive cSCC, and finally metastatic SCC. In this Review we discuss clinical and molecular parameters used to define this range of cutaneous neoplasia and integrate these with the multiple experimental approaches used to study this disease. Insights gained from modeling cSCCs have suggested innovative therapeutic targets for treating these lesions.

A randomized pilot comparative study of topical methyl aminolevulinate photodynamic therapy versus imiquimod 5% versus sequential application of both therapies in immunocompetent patients with actinic keratosis: clinical and histologic outcomes

BACKGROUND

Photodynamic therapy (PDT) and imiquimod are the treatments of choice for actinic keratosis (AK). As they have different mechanisms of action, it seems reasonable to assume that applying both treatments sequentially would be efficacious.

OBJECTIVES

We sought to determine which of these therapeutic modalities provides a better clinical and histologic response in patients with AK and whether sequential use of both was more efficacious than each separately.

METHODS

Patients were randomly assigned to one treatment group: group 1, PDT only; group 2, imiquimod only; or group 3, sequential use of PDT and imiquimod. The primary outcome measure was complete clinical response. Partial clinical response was defined as a reduction of more than 75% in the initial number of lesions. A complete clinicopathologic response was defined as lack of evidence of AK in the biopsy specimen.

RESULTS

In all, 105 patients completed the study (group 1, 40 patients; group 2, 33 patients; group 3, 32 patients). Sequential application of PDT and imiquimod was more efficacious in all the outcome measures. More patients were satisfied with PDT than with the other two modalities (P = .003). No significant differences were observed among the 3 modalities and tolerance to treatment.

LIMITATIONS

Only one cycle of imiquimod was administered. The follow-up period was brief.

CONCLUSIONS

Sequential application of PDT and imiquimod provides a significantly better clinical and histologic response in the treatment of AK than PDT or imiquimod monotherapy. It also produces less intense local reactions and better tolerance and satisfaction than imiquimod monotherapy.

A randomized comparative study of tolerance and satisfaction in the treatment of actinic keratosis of the face and scalp between 5% imiquimod cream and photodynamic therapy with methyl aminolaevulinate

BACKGROUND

Photodynamic therapy (PDT) and imiquimod are two excellent treatments for actinic keratosis but are often not well tolerated by patients.

OBJECTIVES

To ascertain which treatment is better tolerated and which produces greater patient satisfaction. A secondary objective was to determine the factors related to the patient's tolerance to each treatment.

METHODS

Patients with at least five actinic keratosis lesions on the face and scalp were selected. The patients were randomized to receive treatment with PDT with methyl aminolaevulinate or treatment with imiquimod. Tolerance, satisfaction and predisposition to repeat the treatment were evaluated.

RESULTS

Most patients exhibited good or acceptable tolerance to both PDT and imiquimod treatment. There was a higher percentage of patients treated with PDT (93%) who were very satisfied compared with imiquimod (62%) (P=0·004). Most patients treated with either one of the two options would repeat the same treatment. No significant relationship was found between age, sex, working time exposed to the sun, phototype and hair colour and the tolerance to both treatments.

CONCLUSIONS

Both PDT and imiquimod are treatments that are generally well tolerated. While both treatments provide a high level of satisfaction, PDT appears to be slightly superior in this regard.

Imiquimod 3.75% cream (Zyclara) for the treatment of actinic keratoses

INTRODUCTION

actinic keratosis is a premalignant disease with a high incidence and is a strong predictor for the development of squamous cell carcinoma. Various treatment options have been established over recent years, including topical treatment with imiquimod, 5-fluorouracil, diclofenac or photodynamic therapy, cryotherapy and surgical procedures.

AREAS COVERED

this review covers basic and clinical experiences with imiquimod 3.75% for topical treatment of actinic keratosis of the face and balding scalp and its comparators with special focus on imiquimod 5%. It also covers pharmacology of imiquimod 3.5% and its contribution to the current treatment options of actinic keratoses.

EXPERT OPINION

imiquimod 3.75% is an interesting, safe and well-tolerated treatment option for actinic keratoses of the face or balding scalp especially in respect of compliance, as it is indicated for daily use for a shorter time period (2 times, 2-week cycles) and approved for use on larger areas compared with imiquimod 5%. Data from current trials indicate lower efficacy compared with imiquimod 5% cream when applied three times a week for 16 weeks or for two 4-week cycles with a 4-week no-treatment interval, but indicate similar efficacy when compared with a twice-weekly schedule for 16 weeks. An additive effect was observed when combining cryosurgery followed by imiquimod 3.75%.