Non-melanoma skin cancer and solar keratoses. I. Methods and descriptive results of the South Wales Skin Cancer Study

Actinic keratosis: Current challenges and unanswered questions

Actinic keratoses (AK) are common skin lesions associated with chronic exposure to sun. They are believed to be precursors of malignancy as they potentially may progress to invasive squamous cell carcinomas. The goal of current therapies is to reduce the number of AK and to prevent future cancer development. This review aims at providing an overview of the hallmarks of AK and skin field cancerization. We discuss epidemiology trends, risk factors and the state of the art and evidence of the current treatments. We review key figures of AK prevalence from different countries with regard to skin cancer risk and the associated economic burden of AK. We discuss the mutational status in AK lesions and the difficulties encountered by clinicians in evaluating AK visible and invisible lesions, referring to the concept of field cancerization. Based on a systematic literature review, we further evaluate the available treatment options. The presence of subclinical skin alterations in the periphery of visible AK lesions has gained a particular attention as those non-visible lesions are known to contain the same genetic changes as those found in the AK lesions themselves, prompting the concept of 'field cancerization'. Therefore, AK treatment guidelines now recognize the importance of treating the field in patients with AK. A recent systematic literature review and network meta-analysis showed that 5-FU interventions were associated with the best efficacy and a satisfactory acceptability profile compared with other field-directed therapies used in the treatment of AK. Although AK are considered quite common, they lack an accurate descriptive definition and conclusive epidemiologic data. Limited public awareness is a barrier to early and effective treatment, including prevention strategies. While different treatment options are available, there is still a limited understanding of long-term outcomes of treatment as measured by recurrence of cancer prevention.

Global epidemiology of actinic keratosis in the general population: a systematic review and meta-analysis

BACKGROUND

Actinic keratosis (AK) is a common dermatological condition, and among the most common dermatological diagnoses in older populations. Although the prevalence of AK depends on demographic and environmental factors, little is known about the global context of AK.

OBJECTIVES

To provide a comprehensive and updated analysis of the global prevalence rate and incidence of AK in the general population through a systematic review and meta-analysis, and - through subgroup analyses - to identify high-risk phenotypes, demographic and lifestyle risk factors and regional variations in disease prevalence.

METHODS

A systematic search of Embase, MEDLINE, Web of Science and Google Scholar was performed on 20 May 2022. Two reviewers independently screened and assessed the quality of each study using a validated critical appraisal checklist. Epidemiological measurements (e.g. prevalence) from individual studies performed in the general population were then pooled in a random-effects meta-analysis. Subgroup analyses (i.e. population age, geographical region, occupation, sex and study quality) were conducted.

RESULTS

Of the 65 articles that made it through the full-text screening, 60 reported a point prevalence. A meta-analysis of these articles yielded an overall point prevalence of 14% [95% confidence interval (CI) 14-15]. In further analyses, the calculated prevalence rate varied depending on subgroup. The pooled incidence rate from the seven eligible studies analysed was 1928 per 100 000 person-years (PY; 95% CI -439 to 4294).

CONCLUSIONS

This comprehensive meta-analysis provides an updated global prevalence rate of AK of 14%, indicating a significant worldwide disease burden. The incidence rate of AK was found to be 1928 per 100 000 PY, emphasizing a growing public health concern. However, high heterogeneity among studies suggests that various factors influence the AK prevalence rate, necessitating further research to understand the observed differences.

Severity of Local Skin Reactions with 4% 5-Fluorouracil Plus Emollient versus 4% 5-Fluorouracil Alone in Patients with Actinic Keratosis: A Single-Blind Randomised Trial

INTRODUCTION

Topical 5-fluorouracil (5-FU)-containing treatments are effective for actinic keratosis (AK); however, they frequently lead to transient local skin reactions (LSRs), which often result in treatment non-adherence.

METHODS

The aim of this international, phase IV clinical trial was to investigate whether addition of an emollient to topical 4% 5-FU would reduce the frequency and severity of LSRs over 4 weeks of treatment (intervention group) compared with 4% 5-FU alone (control group) in patients with AK. The primary objective was to assess the severity of LSRs (i.e. erythema, flaking/scaling, crusting, swelling, vesiculation/pustulation and erosion/ulceration) at week 4 of treatment (or before, in case of a major local reaction). Key secondary objectives were LSR total scores at weeks 2 and 8, the scores of individual LSR items at each visit, and the proportions of patients with 100% and ≥ 75% AK lesion clearance at week 8.

RESULTS

In total, 141 patients were included in the efficacy analysis (71 in the intervention group and 70 in the control group). There were no statistically or clinically significant differences between the treatment groups in terms of LSR total score at week 4 (overall and by subgroups defined by the number of lesions and patient age at baseline), scores of individual LSR items at any time point, and AK lesion clearance rates at week 8. LSR scores with topical 4% 5-FU alone were lower than expected. Skin reactions were the most common treatment-emergent adverse events in both groups, leading to treatment discontinuation in nine patients (12.3%) in the intervention group and seven (9.9%) in the control group. No new safety signals were observed with the addition of an emollient to 4% 5-FU.

CONCLUSIONS

Daily emollient applications during the 4-week treatment course did not impact the safety and efficacy profile of 4% 5-FU.

Efficacy of sunscreen with photolyase or regular sunscreen associated with topical antioxidants in treating advanced photodamage and cutaneous field cancerization: a randomized clinical trial

BACKGROUND

Several treatments are available for skin with advanced photodamage, which is characterized by the presence of actinic keratoses (AK).

OBJECTIVES

Evaluate the efficacy of using sunscreen with photolyase compared to regular sunscreen, as well as to compare the combination of a topical formulation of antioxidants versus placebo in the treatment of advanced photodamage.

METHODS

This was a randomized, double-blind, factorial clinical trial. Participants with AKs on their forearms were randomized to apply regular sunscreen (SC) or sunscreen with photolyase (SC+P) on both forearms during the day. One of the forearms in each group was randomized again to receive topical antioxidants (AOx), and the other forearm received a placebo cream (both for night application). The four groups were SC/AOx, SC/placebo, SC+P/AOx, and SC+P/placebo. The duration of treatment was 8 weeks. Primary outcomes were total AK clearance, decrease in Forearm Photoaging Scale (FPS), and AK severity scores. Secondary outcomes were reduction in AK count, partial clearance rate, and safety.

RESULTS

Forty participants (80 forearms) were included. All groups showed significant improvement in outcomes at week eight. There were no significant differences between SC and SC+P for either outcome. AOx led to a significant reduction in AK count (22%; p < 0.05). Partial clearance was obtained in 18 (47.4%) forearms treated with AOx and in 9 (23.7%) treated with placebo (p < 0.05). All groups reduced the FPS score, without significant differences among them.

CONCLUSIONS

There is no difference in the treatment of advanced photodamage skin when comparing the use of sunscreen with photolyase and regular sunscreen, and topical antioxidants were more efficient in reducing AK count than placebo.

STUDY LIMITATIONS

Short interval of follow-up and absence of re-evaluation in the absence of treatment were limitations of the present study.

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.

Guidelines of care for the management of actinic keratosis: Executive summary

BACKGROUND

Actinic keratoses (AK) are rough scaly patches that arise on chronically ultraviolet-exposed skin and can progress to keratinocyte carcinoma. Treatment options for AK include topical medications, photodynamic therapy, cryosurgery, and laser ablation.

OBJECTIVE

This executive summary provides a synopsis of the 18 evidence-based recommendations for the treatment of AK detailed in the Guidelines of Care for the Management of Actinic Keratosis.

METHODS

A multidisciplinary workgroup 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, suggesting there are several effective treatments available for AK.

LIMITATIONS

The analysis informing the recommendations was based on the best available evidence at the time it was conducted. The results of future studies may necessitate a revision of current recommendations.

CONCLUSIONS

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

Field cancerization: Definition, epidemiology, risk factors, and outcomes

Field cancerization was first described in 1953 when pathologic atypia was identified in clinically normal tissue surrounding oropharyngeal carcinomas. The discovery of mutated fields surrounding primary tumors raised the question of whether the development of subsequent tumors within the field represented recurrences or additional primary tumors. Since this initial study, field cancerization has been applied to numerous other epithelial tissues, including the skin. Cutaneous field cancerization occurs in areas exposed to chronic ultraviolet radiation, which leads to clonal proliferations of p53-mutated fields and is characterized by multifocal actinic keratoses, squamous cell carcinomas in situ, and cutaneous squamous cell carcinomas. In the first article in this continuing medical education series, we define field cancerization, review the available grading systems, and discuss the epidemiology, risk factors, and outcomes associated with this disease.

Interventions to Prevent Nonmelanoma Skin Cancers in Recipients of a Solid Organ Transplant: Systematic Review of Randomized Controlled Trials

BACKGROUND

Organ transplant recipients are at high risk of developing skin cancer. The benefits and harms of interventions to prevent nonmelanoma skin cancer in solid organ transplant recipients have not been summarized.

METHODS

We searched MEDLINE, Embase, and CENTRAL through April 2018. Risk of bias was assessed using the Cochrane tool, and evidence certainty was evaluated using the Grades of Recommendation, Assessment, Development, and Evaluation process. Prespecified outcomes were nonmelanoma skin cancer, clearance and prevention of keratotic skin lesions, and intervention-specific adverse events.

RESULTS

Ninety-two trials (20 012 participants) were included. The evaluated treatments were cancer-specific interventions (acitretin, imiquimod, photodynamic therapy, nicotinamide, topical diclofenac, and selenium) and immunosuppression regimes (azathioprine, mycophenolate mofetil, calcineurin inhibitors, mammalian target of rapamycin [mTOR] inhibitors, belatacept, induction agents, and withdrawal of calcineurin inhibitors or corticosteroids). Effects on nonmelanoma skin cancer were uncertain for photodynamic therapy (3 trials, 93 participants, risk ratio [RR] 1.42 [95% confidence interval (CI), 0.65-3.11]; low certainty evidence), nicotinamide (2 trials, 60 participants), acitretin (2 trials, 61 participants), and imiquimod (1 trial, 20 participants) compared to control. mTOR inhibitors probably reduced skin cancer compared to calcineurin inhibitors (12 trials, 2225 participants, RR 0.62 [95% CI, 0.45-0.85]; moderate certainty evidence). Photodynamic therapy may cause pain at the treatment site (4 trials, 95 patients, RR 17.09 [95% CI, 4.22-69.26]; low certainty evidence).

CONCLUSIONS

There is limited evidence for the efficacy and safety of specific treatments to prevent nonmelanoma skin cancers among solid organ transplant recipients.

Épidémiologie des kératoses actiniques

Actinic keratosis is a premalignant skin lesion resulting from proliferation of atypical epidermal keratinocytes. Actinic keratoses are very frequent and their prevalence is increasing. Risk factors for actinic keratosis include intrinsic and environmental factors, particularly exposure to ultraviolet radiation and advanced age. The main factor is the exposition to ultraviolet radiation. Better sun protection decreases the risk of actinic keratosis and also the risk of progression to squamous cell carcinoma, even though not all actinic keratoses progress to invasive squamous cell carcinoma. A diagnosis of actinic keratosis should encourage patients to do an annual dermatological screening of skin cancers. Given the economic cost of actinic keratoses, a global approach of health authorities could be interesting for their management. © 2019 Elsevier Masson SAS. All rights reserved. Cet article fait partie du numéro supplément Kératoses actiniques : comprendre et traiter réalisé avec le soutien institutionnel de Galderma International.

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.

Efficacy of Ingenol Mebutate in the Treatment of Actinic Keratoses: A Pre- and Posttreatment Dermoscopic Comparative Analysis

Actinic keratosis (AK) is a common skin lesion in adults which usually occurs on chronically photoexposed areas and considered as a precancerous lesion or a superficial squamous-cell carcinoma. Many classifications have been proposed and its diagnosis is generally clinical but, sometimes, its wide variety of presentations can make diagnosis difficult, even among expert observers. The malignant potential of AKs imposes an early diagnosis and treatment in order to reduce morbidity and mortality, and, for the characterization of photodamaged skin, noninvasive diagnostic techniques, such as dermoscopy, have proved to be useful, while multiple therapeutic strategies, lesion-directed versus field-directed therapies, are available for the treatment of AKs. In this study, we evaluated the efficacy of ingenol mebutate for the treatment of AKs, with a particular focus on patients' compliance, correlating it to clinical and dermoscopic grading, pre- and posttreatment, of these lesions. Fifty-two enrolled patients with AKs received treatment with ingenol mebutate gel (0.015% for face and scalp; 0.05% for trunk and extremities) and multiple dermatological evaluations. End points of the study were complete and partial clearance of clinically visible AKs on day 90. All acquired data were recorded and statistical analyses were performed. Univariate and multivariate analyses were used to identify possible predictive factors. We retrospectively analyzed patient-related and lesion-related factors to identify which variables, among age, gender, lesion site, pain, LSR score, and pretreatment clinical and dermoscopic grading, could independently predict the response to ingenol mebutate treatment. Our findings showed that pretreatment dermoscopic grade II represents an independent predictive factor of the efficacy of ingenol mebutate therapy (OR=14.78, 95% CI: 1.83–119.59, P=0.012) and that response rates differ on the basis of the treated anatomical sites (OR=0.16, 95% CI: 0.03–0.85, P=0.031). Data from this study provide evidence that ingenol mebutate gel is an effective treatment for AK, with relative ease of use, short exposure, and rapid resolution of local reactions, benefits contributing to high adherence of this therapy. Moreover, dermoscopic analysis of skin lesions offers more information than clinical evaluation alone and can be helpful in identifying different groups of AKs, thus selecting the adequate therapeutic choice.

Patient preferences for topical treatment of actinic keratoses: a discrete-choice experiment

BACKGROUND

The treatment of actinic keratosis (AK) is a potentially effective strategy for the prevention of cutaneous squamous cell carcinoma (cSCC). However, the patient perspective on potential benefits of AK treatment in terms of skin cancer reduction has received little attention to date.

OBJECTIVES

(i) To investigate patient preferences for topical treatments for AK using a discrete-choice experiment (DCE); (ii) to evaluate patient willingness to trade between clinical benefit and medical burden.

METHODS

The DCE was conducted as part of a study to establish the feasibility of a phase III randomized controlled trial evaluating the prevention of cSCC using currently available topical interventions. Preferences were elicited by asking patients to make a series of choices between treatment alternatives with different hypothetical combinations of attribute levels. Willingness to trade between treatment attributes was estimated using a flexible-choice model that allows for the heterogeneity of patient preferences.

RESULTS

A total of 109 patients with AK completed the DCE. The majority of patients who expressed valid preferences were willing to accept some reduction in both prophylactic and cosmetic efficacy to reduce the burden of the treatment regimen, the severity of skin reaction and other adverse effects. Patients may reject treatment if the perceived therapeutic benefit is outweighed by the subjective burden of treatment.

CONCLUSIONS

Evidence of significant variation in the perceived utility of treatments across patients highlights the importance of taking individual patient preferences into account to improve AK treatment acceptability and adherence.

Validity and Reliability of the Dutch Adaptation of the Actinic Keratosis Quality of Life Questionnaire (AKQoL)

BACKGROUND

The Actinic Keratosis Quality of Life Questionnaire (AKQoL) is a disease-specific instrument to measure the impact of actinic keratosis (AK) on patients' lives.

OBJECTIVE

To validate and test the psychometric properties of the AKQoL translated into the Dutch language (AKQoL-NL).

METHODS

All new patients ≥50 years of age with untreated AK in a university medical center and a general hospital between August 2014 and August 2015 were eligible. The AKQoL was obtained and repeated after 2 weeks. The feasibility was tested by missing responses and response distribution. The internal consistency reliability of each domain was investigated with the Cronbach alpha, and test-retest reliability and validity with the Spearman correlation coefficient. AKQoL scores were compared to the Skindex-17 for convergent validity and to the Groningen Frailty Indicator scores for divergent validity.

RESULTS

A total of 153 of 190 eligible patients consented to participate. Feasibility analysis showed that none of the items missed ≥10% of responses but 5 of the 9 items showed floor effect. The AKQoL subscales showed a moderate internal consistency (Cronbach α = 0.235-0.468) and an excellent test-retest reliability (interclass correlation coefficient = 0.997-1). The AKQoL correlated poorly with the symptom component and moderately with the psychosocial component of the Skindex-17 (ρ = -0.015 to 0.346 and 0.324 to 0.501, respectively), which is less than expected. The AKQoL scored poorly in both of the Groningen Frailty Indicator (GFI) components (ρ = -0.97 to 0.12 and 0.185 to 0.276, respectively), as expected.

CONCLUSION

The AKQoL-NL is a feasible, moderately valid, and moderately reliable health-related quality of life questionnaire.

Are actinic keratoses really squamous cell cancer? How do we know if they would become malignant?

Actinic keratosis (AK) is a very common skin disease caused by chronic sun exposure. AKs have historically been characterized as being "precancerous" or "premalignant." It is true that these lesions do not possess metastatic potential, because they are confined to the epidermis, but it is not accurate to deem them "premalignant." AK qualifies as a malignant neoplasm, because it also fulfills criteria for malignancy in classic pathology, namely, the capability, or potential, to kill by either destruction of tissue locally or by metastasis widely. In this context, AK is considered now by many a carcinoma in situ and can persist or progress to invasive squamous cell carcinoma (iSCC), which rarely metastasizes. Through this controversy, which speaks to an issue we have been debating for at least a century, we should like to start a constructive debate to reach a unanimous conclusion considering the various theories and points of view in the literature.

Influence of Information Framing on Patient Decisions to Treat Actinic Keratosis

Importance

Actinic keratosis (AK) is a skin growth induced by UV light exposure that requires long-term management because a small proportion of the disease can progress to squamous cell carcinoma. The influence of how clinicians frame or present information to patients may affect decision making about AK.

Objective

To evaluate the differences in patients' decisions on whether to receive treatment for AK related to information presentation or choice framing.

Design, Setting, and Participants

A prospective survey study was performed from June 1 to July 31, 2016, in participants who were able to read English. Participants were recruited through the Penn State Milton S. Hershey Dermatology Clinic and an online survey site. The survey was conducted through an online portal. A total of 571 individuals were recruited. Regression analysis, correlation coefficient analysis, and test-retest validation were conducted.

Main Outcomes and Measures

The proportions of patients choosing to receive treatment for AK. Analyses were performed to adjust for age, sex, educational level, history of skin cancer, and history of AK.

Results

Of the 571 recruited participants, 539 (94.4%) returned completed surveys. The mean (SD) age of respondents was 42.9 (17.8) years; 306 (56.8%) were women. The decision to receive treatment for AK varied from 57.7% (n = 311) to 92.2% (n = 497) for the 5 scenarios presented in the questions (P < .001). The question that presented AK as a "precancer" had the highest proportion of participants who preferred treatment (497 [92.2%]). Two questions that presented the risk of AK as not progressing to cancer had the lowest proportion of individuals who chose treatment (311 [57.7%] and 328 [60.9%]). Participants from the clinic and from the online portal were significantly different in age (mean [SD] age, 56.1 [17.6] vs 33.3 [10.0] years), sex (145 [63.6%] vs 161 [51.8%] were females), educational level (40 [17.5%] vs 80 [25.7%] had completed some graduate school), history of AK (46 [20.2%] vs 19 [6.1%] answered yes), and history of skin cancer (76 [33.3%] vs 15 [4.8%] answered yes) (all P ≤ .001). Based on a regression analysis, age, sex, and previous diagnosis of skin cancer were not significantly associated with the participants' responses.

Conclusions and Relevance

This study found that patients' decisions on whether to receive treatment for AK is significantly affected by physician wording, especially with alterations in the presentation of risk of malignant transformation.

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.

Can the lesions induced with actinic keratosis become an enigma for dermatologists? Results of an open perspective study

Different face skin diseases (basal cell carcinoma, actinic keratosis, rosacea, solar elastosis, etc.) could clinically manifest itself as erythematic patches, pimples or plagues. It is very hard to make the clinical exclusion in some cases of these diseases since their characters can partially overlap or certain lesion can mimic another one especially in the cases of skin areas affected with sun. Therefore, the histopathological analysis remains the “golden standard” of the dermatological diagnosis at skin diseases. Our study has shown that certified dermatologists detect actinic keratosis (AK) of face/head skin of I/II levels very well. Verdicts of dermatologists and pathomorfologists are congruent on account of diagnosis in 90,7% cases. Diseases clinically excluded as AK revealed as malignant neoplasms (basal cell carcinoma) in less than 1% of case lesions.

The Majority of Cutaneous Squamous Cell Carcinomas Arise in Actinic Keratoses

Background:

Retrospective studies have given conflicting results with respect to how many cutaneous squamous cell carcinomas (SCCs) arise in actinic keratoses (AK).

Objective:

This study was conducted to determine what percentage of SCCs arise in AKs and to obtain more information about two histological features of SCCs, namely, thickness and ulceration.

Methods:

A prospective study was done of all SCCs treated by the authors during one calendar year.

Results:

Two hundred eight patients with SCC were entered into the study. An AK was contiguous with an SCC in 72% of the cases. This was taken as evidence that the SCC arose in the AK. Men presented with thicker and more ulcerated SCCs than women, but these were not statistically significant: p = 0.06 for thickness and p = 0.07 for ulceration. Ulcerated SCCs were more likely to arise on the head and neck (p = 0.02), on patients who had multiple skin cancers ( p = 0.005), and on patients who had a family history of skin cancer ( p = 0.03).

Conclusion:

Actinic keratoses need to be removed before they turn into SCCs. The prognostic significance of ulceration of cutaneous SCCs needs to be determined.

Current perspective on actinic keratosis: a review

Actinic keratoses (AKs) are common, with prevalence in the U.S.A. estimated at almost 40 million in 2004 and annual costs of > $1 billion (U.S.D.). However, there is no universally accepted definition of AK and thus it is difficult to identify reliably. AKs are lesions of epidermal keratinocytic dysplasia that result from chronic sun exposure and have the ability to progress to invasive squamous cell carcinoma (SCC), but clinicians disagree about whether AKs are premalignant lesions, superficial SCCin situ or epiphenomena of chronically sun-damaged skin. Yearly AK to SCC progression rates of 0·6% were reported in an elderly population with multiple prior keratinocyte carcinomas (KCs); and rates of spontaneous AK regression have been reported to be > 50%, but regressed lesions often reappear. As AKs have both cosmetic consequences and potential for malignant transformation, there are multiple reasons for treatment. There is no current agreement on the most efficacious treatment, but 5-fluorouracil has been shown to both prevent and treat AKs, and imiquimod and photodynamic therapy may have the best cosmetic outcomes. AKs may be treated to improve appearance and relieve symptoms, but the keratinocytic dysplasia that gives rise to malignancy, and sometimes appears as an AK, may be what actually threatens patient health. Thus, treatments should aim to decrease the risk of KC or facilitate KC diagnosis by reducing the potential for misidentification created when a KC appears in a field of AKs. Improved agreement among clinicians on AK definition may improve management.

Non-melanoma Skin Cancer in Canada Chapter 3: Management of Actinic Keratoses

Background

Actinic keratosis (AK) and cheilitis (AC) are lesions that develop on photodamaged skin and may progress to form invasive squamous cell carcinomas (SCCs).

Objective

To provide guidance to Canadian health care practitioners regarding management of AKs and ACs.

Methods

Literature searches and development of graded recommendations were carried out as discussed in the accompanying introduction (chapter 1 of the NMSC guidelines).

Results

Treatment of AKs allows for secondary prevention of skin cancer in sun-damaged skin. Because it is impossible to predict whether a given AK will regress, persist, or progress, AKs should ideally be treated. This chapter discusses options for the management of AKs and ACs.

Conclusions

Treatment options include surgical removal, topical treatment, and photodynamic therapy. Combined modalities may be used in case of inadequate response. AKs are particularly common following the longterm immunosuppression in organ transplant patients, who should be monitored frequently to identify emerging lesions that require surgery.

Italian expert consensus for the management of actinic keratosis in immunocompetent patients

Actinic keratosis (AK) is a common skin disease which can potentially progress to invasive squamous cell carcinoma (iSCC). Given that mortality rates and health-care cost associated with iSCC are substantial, the management of AK represents an important public health issue. Several effective lesion-directed and field-directed treatments are available. Ablative procedures (e.g. cryosurgery, excision, laser ablation, curettage alone or with electrodessication) are considered cost-effective options for solitary lesions. Field-directed therapies (e.g. Ingenol Mebutate, imiquimod, PDT, 5-Fluorouracile, diclofenac 3%, 5-FU + Salicylic acid) can be used over large epidermal surfaces and are directed to treat both individual visible lesions and cancerization fields. In order to provide guidance for management choice in clinical practice, several guidelines concerning the diagnosis and treatment of AK have been published in the past decade. However, the introduction of novel therapeutic options requires continuous updates of recommendations and adaptation to national contexts. The present review summarizes the existing evidence and reports the results of a consensus workshop on the management of AK.

A cost-utility analysis of ingenol mebutate gel for the treatment of actinic keratosis: a Scottish perspective

BACKGROUND

Actinic keratosis (AK) is a UV-induced, pre-malignant skin condition that is common in adults over 60 years of age with fair skin in Scotland. The most commonly prescribed first-line treatment for AK in Scotland is currently diclofenac gel (3 %). Ingenol mebutate gel is a recently developed topical therapy available in two strengths for the treatment of AK lesions on the face and scalp (150 mcg/g once daily for 3 consecutive days) or trunk and extremities (500 mcg/g once daily for 2 consecutive days).

OBJECTIVE

To compare the cost-effectiveness of two strengths of ingenol mebutate gel developed to treat AK lesions on the face and scalp (150 mcg/g once daily for 3 consecutive days) or trunk and extremities (500 mcg/g once daily for 2 consecutive days) with other first-line AK therapies including diclofenac gel, 5-FU, 5-FU/salicylic acid, and cryotherapy for the first-line treatment of AK in adult patients, from the perspective of the National Health Service (NHS) in Scotland.

METHODS

A cost-utility analysis was conducted using a decision-tree approach to calculate the costs and benefits of different treatment strategies for AK on the face and scalp or trunk and limbs over a 12-month time horizon. Data on the relative efficacy of treatments were obtained from a systematic literature review and meta-analysis. Utility scores and resource-use data were obtained from published sources.

RESULTS

Over 12 months, ingenol mebutate 150 mcg/g gel and 500 mcg/g gel were cost-effective compared with the most commonly used topical therapy in Scotland, diclofenac (3 %) gel, at a willingness-to-pay threshold of £20,000 per QALY, with a minimal additional cost of £43 and £105, respectively per QALY gained.

CONCLUSIONS

Ingenol mebutate gel is a cost-effective therapy for the first-line treatment of AK from a Scottish NHS perspective.

Health related quality of life in patients with actinic keratosis--an observational study of patients treated in dermatology specialist care in Denmark

Background

Actinic keratosis (AK) is a common skin condition that may progress to non-melanoma skin cancer (NMSC). The disease may influence Health Related Quality of Life (HRQoL), but studies of HRQoL in patients with AK are limited.

The purpose of the study was to analyze HRQoL in patients with different severity levels of AK treated in dermatology specialist care using generic and disease-specific HRQoL instruments and to analyze their relationship.

Methods

AK patients who visited dermatological clinics in Denmark were included in an observational, cross-sectional, study in a multi-center setting. Dermatologists assessed AK severity and patients completed: Actinic Keratosis Quality of Life Questionnaire (AKQoL), Dermatology Life Quality Index (DLQI), and EQ-5D-5 L including EQ-VAS. Differences between categorical subgroups were tested with Wilcoxon rank-sum test. The relationship between instruments was analyzed with the Spearman correlation test.

Results

A total of 312 patients were included in the analyses. Patients reported impairment in the disease specific HRQoL instrument AKQoL (mean AKQoL 6.7, DLQI 2, EQ-5D-5 L 0.88, and EQ-VAS 79). HRQoL was least affected in patients with mild actinic disease, whereas patients with severe actinic damage suffered from further impaired HRQoL (mean AKQoL 10.1 and DLQI 4.6). Correlations between DLQI and AKQoL were moderate, whereas the correlations between DLQI and EQ-5D-5 L and between AKQoL and EQ-5D-5 L were weak.

Conclusions

Patients with severe actinic damage showed more impairment in HRQoL than those with mild disease. Correlations between instruments suggest that they are complementary as they measure different aspects of HRQoL and are used for different purposes.

Non-melanoma Skin Cancer in Canada Chapter 1: Introduction to the Guidelines

BACKGROUND

Non-melanoma skin cancer (NMSC), including basal and squamous cell carcinoma, represents the most common malignancy.

OBJECTIVE

The aim of this document is to provide guidance to Canadian health care practitioners on NMSC management.

METHODS

After conducting a literature review, the group developed recommendations for prevention, management, and treatment of basal cell carcinomas, squamous cell carcinomas, and actinic keratoses. These tumour types are considered separately in the accompanying articles. The Grading of Recommendations Assessment, Development and Evaluation system was used to assign strength to each recommendation.

RESULTS

This introduction describes the scope and structure of the guidelines and the methods used to develop them. The epidemiology of NMSC is reviewed, as are the pathophysiologic changes occurring with damage to the skin, which lead to the formation of actinic keratoses and invasive squamous or basal cell carcinomas.

CONCLUSIONS

This introduction describes the need for primary prevention and offers an overview of treatment options that are discussed in later chapters of the guidelines.

Tumor evolution. High burden and pervasive positive selection of somatic mutations in normal human skin

How somatic mutations accumulate in normal cells is central to understanding cancer development but is poorly understood. We performed ultradeep sequencing of 74 cancer genes in small (0.8 to 4.7 square millimeters) biopsies of normal skin. Across 234 biopsies of sun-exposed eyelid epidermis from four individuals, the burden of somatic mutations averaged two to six mutations per megabase per cell, similar to that seen in many cancers, and exhibited characteristic signatures of exposure to ultraviolet light. Remarkably, multiple cancer genes are under strong positive selection even in physiologically normal skin, including most of the key drivers of cutaneous squamous cell carcinomas. Positively selected mutations were found in 18 to 32% of normal skin cells at a density of ~140 driver mutations per square centimeter. We observed variability in the driver landscape among individuals and variability in the sizes of clonal expansions across genes. Thus, aged sun-exposed skin is a patchwork of thousands of evolving clones with over a quarter of cells carrying cancer-causing mutations while maintaining the physiological functions of epidermis.

Skin Cancer Screening on a Fishing Island and in an Inland Agricultural Area of Japan

We performed skin cancer screening from 2000 to 2004 at two locations in Japan's Oita Prefecture: Himeshima, a small fishing island, and Naoiri, an inland agricultural area. We found 108 and 21 cases of AK in Himeshima and Naoiri, respectively. None of the AKs transformed into SCC, and 21.7% of the AKs underwent spontaneous remission during our observation period. The prevalence and incidence of AK in Himeshima were five times higher than in Naoiri: 1,399 and 826 per 100,000 population, respectively, in the fishing village, vs. 261 and 164 in the agricultural community. Seven and three cases of BCC were observed in Himeshima and Naoiri, respectively. There were two cases of SCC in Himeshima. The highest risk ratio of skin types I to III was 9.2 in Himeshima. Although people engaged in outdoor occupations are thought to be more prone to skin cancer and precancerous skin lesions, our results suggested different potentials for AK in people engaged in different outdoor occupations.

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.

Skin cancer - an overview for dentists

Skin cancer is common and an increasing problem in the UK. It frequently occurs on the head and neck skin. A significant proportion of the adult population in the UK visits the dentist each year, thus making dental practitioners ideally placed to identify suspicious lesions, which could be skin cancer, as part of their routine extra-oral examination. These patients can then be referred on to hospital or their GP for further management. The dentist can also give advice on risk factors and self-monitoring to patients. This paper aims to describe the risk factors, pathology, presentation and treatments for the three most common forms of skin cancer - basal and squamous cell carcinomas, and malignant melanoma, to give the dental practitioner the knowledge and confidence to examine for and identify these skin cancers.

The natural history of actinic keratosis: a systematic review

Knowledge about the development of untreated actinic keratosis (AK) and risk of progression into squamous cell carcinoma (SCC) is important. Therefore, we set out to synthesize primary data on the natural history of AK. We carried out a systematic literature search (Medline, Medline in Process, Embase, Cochrane) of studies on the natural course of AK, regarding (i) progression and regression rates per lesion-year, (ii) changes in total lesion counts over time, and (iii) spontaneous field regression and recurrence rates, taking into account studies on participants without immunosuppression and history of skin cancer, immunosuppressed patients and participants with a history of skin cancer and sunscreen use. Twenty-four eligible studies were identified providing data on at least one of the outcomes. Progression rates of AK to SCC ranged from 0% to 0·075% per lesion-year, with a risk of up to 0·53% per lesion in patients with prior history of nonmelanoma skin cancer. Rates of regression of single lesions ranged between 15% and 63% after 1 year. The data available on recurrence rates of single lesions 1 year after regression indicate a recurrence rate of 15-53%. Data on the relative change of total AK count over time are heterogeneous, and range from -53% to +99·1%. Spontaneous complete field regression rates range from 0% to 21%, with recurrences in 57%. In general, the available data are limited. Important methodological limitations apply. Currently, no reliable estimates concerning the frequency of AK developing into invasive carcinoma can be given, and further studies are needed.

Spanish adaptation of the European guidelines for the evaluation and treatment of actinic keratosis

Current trends in our setting indicate that the prevalence of actinic keratosis and similar diseases will increase in coming years and impose a greater burden on health care resources. A long list of clinical features must be taken into account when approaching the treatment of actinic keratosis. Until recently, therapeutic approaches focused solely on ablative procedures and the treatment of individual lesions and did not take into account areas of field cancerization. Now that the therapeutic arsenal has grown, standardized criteria are needed to guide the optimal choice of treatment for each patient. The elaboration of evidence-based consensus recommendations for the diagnosis and treatment of actinic keratosis generates knowledge that will help clinicians to deliver the highest level of care possible, standardizing decision-making processes and enhancing awareness among all the health professionals involved in the care pathway.

Actinic keratosis: rationale and management

Actinic keratoses (AKs) are common skin lesions heralding an increased risk of developing squamous cell carcinoma (SCC) and other skin malignancies, arising principally due to excessive ultraviolet (UV) exposure. They are predominantly found in fair-skinned individuals, and increasingly, are a problem of the immunosuppressed. AKs may regress spontaneously, remain stable or transform to invasive SCC. The risk of SCC increases for those with more than 5 AKs, and the majority of SCCs arise from AKs. The main mechanisms of AK formation are inflammation, oxidative stress, immunosuppression, impaired apoptosis, mutagenesis, dysregulation of cell growth and proliferation, and tissue remodeling. Human papilloma virus has also been implicated in the formation of some AKs. Understanding these mechanisms guides the rationale behind the current available treatments for AKs. One of the main principles underpinning the management of AKs is that of field cancerization. Wide areas of skin are exposed to increasing amounts of UV light and other environmental insults as we age. This is especially true for the head, neck and forearms. These insults do not target only the skin where individual lesions develop, but also large areas where crops of AKs may appear. The skin between lesions is exposed to the same insults and is likely to contain as-yet undetectable preclinical lesions or areas of dysplastic cells. The whole affected area is known as the ‘field’. Management is therefore divided into lesion-directed and field-directed therapies. Current therapies include lesion-directed cryotherapy and/or excision, and topical field-directed creams: 5-fluorouracil, imiquimod, diclofenac, photodynamic therapy and ingenol mebutate. Combining lesion- and field-directed therapies has yielded good results and several novel therapies are under investigation. Treatment is variable and tailored to the individual making a gold standard management algorithm difficult to design. This literature review article aims to describe the rationale behind the best available therapies for AKs in light of current understanding of pathophysiology and epidemiology. A PubMed and MEDLINE search of literature was performed between January 1, 2000 and September 18, 2013. Where appropriate, articles published prior to this have been referenced. This is not a systematic review or meta-analysis, but aims to highlight the most up to date understanding of AK disease and its management.

Prevalence of actinic keratosis and its risk factors in the general population: the Rotterdam Study

Limited data are available on the prevalence and risk factors of actinic keratoses (AKs). Within the Rotterdam Study, full-body skin examinations were performed among participants aged 45 years or older to estimate the age- and sex-standardized prevalence of AK and its associated risk factors. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for associations between risk factors and the presence of 1-3, 4-9, and ≥ 10 AKs. Of the 2,061 inspected cohort members (mean age 72 years), 21% had 1-3, 9% had 4-9, and 8% had ≥ 10 AKs. AK prevalence was 49% (95% CI: 46-52%) for men and 28% (26-31%) for women. Male gender, older age, light pigmentation status, severe baldness, skin wrinkling, and high tendency for sunburn were significantly associated with extensive actinic damage (≥ 10 AKs) in the multivariate analyses. Especially bald males were at an increased risk of severe actinic skin damage (adjusted OR=7.0 (3.8-13.1)). The prevalence of AK is very high, especially among elderly bald males. The prevention and management of AK is a true challenge for patients, physicians, and health-care policymakers.

Prevalence and awareness of actinic keratosis: barriers and opportunities

Actinic keratoses (AKs) are common skin lesions that appear after long-term exposure to ultraviolet radiation. The presence of AKs is associated with an increased risk for development of nonmelanoma skin cancer. AKs vary widely in clinical and histologic presentation, which contributes to inadequate identification and presents challenges for consensus classification. Clinically adequate reduction in AK prevalence requires a multifaceted approach. There is a reasonable need to increase awareness and knowledge about AK, including symptoms, prevention, and associated risk of nonmelanoma skin cancer, especially among the public at large. Safe and effective treatment strategies are needed to optimize clearance of AKs, ideally to prevent progression to invasive cutaneous neoplasia.

The role of ingenol mebutate in the treatment of actinic keratoses

Actinic keratoses (AK) are the most common premalignant pathology seen in dermatological practice and represent a burgeoning burden upon health services. Increasingly recognized is the damage to surrounding, perilesional skin, forming the premise for field-directed therapy. Ingenol mebutate gel is a novel agent for field-directed treatment of AK, requiring only 2 or 3 days of application. Following an overview of existing treatment modalities, the authors review recent trials and safety data pertaining to the use of ingenol mebutate gel and discuss its role in the treatment of AK.

Chemoprevention of nonmelanoma skin cancer with celecoxib: a randomized, double-blind, placebo-controlled trial

Background

Preclinical studies indicate that the enzyme cyclooxygenase 2 plays an important role in ultraviolet-induced skin cancers. We evaluated the efficacy and safety of celecoxib, a cyclooxygenase 2 inhibitor, as a chemopreventive agent for actinic keratoses, the premalignant precursor of nonmelanoma skin cancers, and for nonmelanoma skin cancers, including cutaneous squamous cell carcinomas (SCCs) and basal cell carcinomas (BCCs).

Methods

A double-blind placebo-controlled randomized trial involving 240 subjects aged 37–87 years with 10–40 actinic keratoses was conducted at eight US academic medical centers. Patients were randomly assigned to receive 200 mg of celecoxib or placebo administered orally twice daily for 9 months. Subjects were evaluated at 3, 6, 9 (ie, completion of treatment), and 11 months after randomization. The primary endpoint was the number of new actinic keratoses at the 9-month visit as a percentage of the number at the time of randomization. In an intent-to-treat analysis, the incidence of actinic keratoses was compared between the two groups using t tests. In exploratory analyses, we evaluated the number of nonmelanoma skin cancers combined and SCCs and BCCs separately per patient at 11 months after randomization using Poisson regression, after adjustment for patient characteristics and time on study. The numbers of adverse events in the two treatment arms were compared using χ² or Fisher exact tests. All statistical tests were two-sided.

Results

There was no difference in the incidence of actinic keratoses between the two groups at 9 months after randomization. However, at 11 months after randomization, there were fewer nonmelanoma skin cancers in the celecoxib arm than in the placebo arm (mean cumulative tumor number per patient 0.14 vs 0.35; rate ratio [RR] = .43, 95% confidence interval [CI] = 0.24 to 0.75; P = .003). After adjusting for age, sex, Fitzpatrick skin type, history of actinic keratosis at randomization, nonmelanoma skin cancer history, and patient time on study, the number of nonmelanoma skin cancers was lower in the celecoxib arm than in the placebo arm (RR = 0.41, 95% CI = 0.23 to 0.72, P = .002) as were the numbers of BCCs (RR = 0.40, 95% CI = 0.18 to 0.93, P = .032) and SCCs (RR = 0.42, 95% CI = 0.19 to 0.93, P = .032). Serious and cardiovascular adverse events were similar in the two groups.

Conclusions

Celecoxib may be effective for prevention of SCCs and BCCs in individuals who have extensive actinic damage and are at high risk for development of nonmelanoma skin cancers.

Actinic keratosis: facts and controversies

Actinic keratoses are common lesions that are generally clinically diagnosed. Although currently most actinic keratoses are treated, whether this is truly necessary is debated. Treatment of all actinic keratoses is advocated because preliminary evidence indicates that actinic keratoses may progress to squamous cell carcinomas. Some also consider actinic keratoses equivalent to squamous cell carcinoma.

Epidemiology and risk factors for varicose veins among older people: cross-sectional population study in the UK

Background

There are many hypotheses concerning risk factors for the development of varicose veins based mostly on pathophysiological plausibility. Population studies have been carried out mostly on the middle aged with relatively few on elderly populations.

Objectives

To investigate epidemiological risk factors for varicose veins in an elderly population in the UK.

Methods

The South Wales Skin Cancer study – an examination survey undertaken between 1988 and 1991 of a random sample ( n = 792) drawn from all patients aged 60 and over registered with a general practitioner in South Glamorgan. Exposure variables were obtained from a structured administered questionnaire combined with clinical examination. Unadjusted and adjusted odds ratios were estimated using logistic regression.

Results

The response rate was 71% with an average age of 71 years (range 60–97). The age-adjusted prevalence of trunk varices was 63.2% (95% confidence interval [CI] 57.9–68.4%) in men and 57.0% (95% CI 50.6–63.4%) in women. In a multiple logistic regression the significant risk factors for varicose veins were increasing age ( P value = 0.001), obesity (odds ratio [OR] 3.28, 95% CI 1.25–8.63, P = 0.042), self-reported history of deep vein thrombosis (DVT) (OR 3.19, 1.16–8.78, P = 0.024) and history of hypertension (OR 0.58, 0.38–0.89, P = 0.013). The results for gender suggested that women were at greater risk than men, but this was not statistically significant (OR 1.53, 0.99–2.38, P = 0.056).

Conclusion

Trunk varices occur very commonly in older age groups with increasing age, obesity and possibly female sex as risk factors. Associations found with DVT and hypertension were based on history alone and must be interpreted with caution.

An economic evaluation of topical treatments for actinic keratosis

Actinic keratoses (AK) commonly occur as lesions, in sun-exposed areas. Various treatment modalities exist for their removal. We assessed the cost-effectiveness in 2007 of topical treatments (5-fluorouracil, imiquimod) and photodynamic therapy with methyl aminolevulinate (MAL-PDT) for AK under the perspective of the UK National Health Service (NHS) in England and Wales over two lines of treatment. We used a decision tree analytical approach. Efficacy data were taken from published trial literature for two investigator-assessed outcomes: 'complete clinical response' and 'excellent cosmetic outcome'. MAL-PDT at first line followed by various second-line treatments provided the greatest probability of complete clinical response (91.7%), but MAL-PDT at first line followed by further MAL-PDT as the second-line treatment provided the greatest probability of excellent cosmetic outcome (73.6%). The cost of MAL-PDT was 437 pounds sterling after two lines of treatment if MAL-PDT was that second-line treatment or 418 pounds sterling if various treatments were offered at second line. The probabilistic analysis produced consistent results. Based on this model, the costs and effectiveness of MAL-PDT in the UK NHS compare well with other treatments for AK.