How to treat actinic keratosis? An update

International time trends and differences in topical actinic keratosis therapy utilization

Background

Actinic Keratoses (AK) are precancerous lesions that can lead to Squamous Cell Carcinoma. International differences in the utilization of topical medications to treat AK are not well described.

Objectives

To describe international differences in topical AK medication utilization, including associations of countries' economic status with AK medication utilization.

Methods

We used IQVIA MIDAS pharmaceutical sales data for 65 countries (42 high-income, 24 middle-income) from April 2011 to December 2021. We calculated each country's quarterly utilization of medications in grams per 1000 population. We used univariable linear regression to assess the association between country economic status and AK medication utilization.

Results

High-income countries used 15.37 more grams per 1000 population of 5-fluorouracil (95% CI: 9.68, 21.05), 4.64 more grams per 1000 population of imiquimod (95% CI: 3.45, 5.83), and 0.32 more grams per 1000 population of ingenol mebutate (95% CI: 0.05, 0.60).

Limitations

Missing medication utilization data for some countries.

Conclusion

High-income countries use more topical AK therapies than middle-income countries.

Topically Applied Therapies for the Treatment of Skin Disease: Past, Present, and Future

The purpose of this review is to summarize essential biological, pharmaceutical, and clinical aspects in the field of topically applied medicines that may help scientists when trying to develop new topical medicines. After a brief history of topical drug delivery, a review of the structure and function of the skin and routes of drug absorption and their limitations is provided. The most prevalent diseases and current topical treatment approaches are then detailed, the organization of which reflects the key disease categories of autoimmune and inflammatory diseases, microbial infections, skin cancers, and genetic skin diseases. The complexity of topical product development through to large-scale manufacturing along with recommended risk mitigation approaches are then highlighted. As such topical treatments are applied externally, patient preferences along with the challenges they invoke are then described, and finally the future of this field of drug delivery is discussed, with an emphasis on areas that are more likely to yield significant improvements over the topical medicines in current use or would expand the range of medicines and diseases treatable by this route of administration. SIGNIFICANCE STATEMENT: This review of the key aspects of the skin and its associated diseases and current treatments along with the intricacies of topical formulation development should be helpful in making judicious decisions about the development of new or improved topical medicines. These aspects include the choices of the active ingredients, formulations, the target patient population's preferences, limitations, and the future with regard to new skin diseases and topical medicine approaches.

Topical GZ21T Inhibits the Growth of Actinic Keratoses in a UVB-Induced Model of Skin Carcinogenesis

Actinic keratoses (AKs) are premalignant intraepidermal neoplasms that occur as a result of cumulative sun damage. AKs commonly relapse, and up to 16% undergo malignant transformation into cutaneous squamous cell carcinoma. There is a need for novel therapies that reduce the quantity and surface area of AKs as well as prevent malignant transformation to cutaneous squamous cell carcinomas. We recently showed that GZ17-6.02, an anticancer agent composed of curcumin, haramine, and isovanillin, inhibited the growth of H297.T cells. This study evaluated the efficacy of a topical formulation of GZ17-6.02, known as GZ21T, in a murine model of AK generated by exposing SKH1 mice to UVR. Treatment of mice with topical GZ21T inhibited the growth of AKs by decreasing both lesion count (P = 0.012) and surface area occupied by tumor (P = 0.002). GZ21T also suppressed the progression of AKs to cutaneous squamous cell carcinoma by decreasing the count (P = 0.047) and surface area (P = 0.049) of lesions more likely to represent cutaneous squamous cell carcinoma. RNA sequencing and proteomic analyses revealed that GZ21T suppressed several pathways, including MAPK (P = 0.025), phosphoinositide 3-kinase-protein kinase B (P = 0.04), HIF-1α (P = 0.016), Wnt (P = 0.025), insulin (P = 0.018), and ERBB (P = 0.016) signaling. GZ21T also upregulated the autophagy-promoting protein AMPK while suppressing proteins such as PD-L1, glutaminase, pAkt1 S473, and eEF2K.

The Copenhagen Actinic Keratosis Study (COAKS). A decentralised clinical trial to evaluate tolerability, safety and efficacy of daily field-directed topical treatment with cytosolic phospholipase A2 inhibitor, AVX001, in participants with actinic keratosis: protocol for a randomised controlled phase I/IIa trial

INTRODUCTION

Actinic keratosis (AK) is the most common precancerous skin condition caused by long-term UV exposure. Given the high recurrence rate of 15%-53%, identifying safe and effective treatment options is warranted. AVX001, a cytosolic phospholipase A₂α (cPLA₂α) enzyme inhibitor, is a novel anti-inflammatory drug for field-directed, self-administered, topical therapy of AK.

METHODS AND ANALYSIS

This study is a single-centre, randomised, vehicle-controlled, double-blind, parallel-group hybrid clinical trial in adults with multiple AK lesions Olsen grade 1 or 2. The hybrid design combines decentralised participant tasks and assessments with conventional in-clinic visits. Recruitment using targeted advertising on social media and eligibility prescreening are conducted via the Studies&Me online recruitment platform. Participants (n=60) are randomly assigned to 1 of 3 treatment arms: AVX001 gel 1%, AVX001 gel 3% or vehicle gel. The trial consists of a 4-week treatment period with daily field-directed topical application of the gel and an 8-week follow-up period. Participants attend in-clinic visits at baseline, week 4 and week 12. The remote participant trial tasks include questionnaires and upload of smartphone-obtained photos of the treated skin area using a study-specific web-based app. Both remote and in-clinic assessments of safety and efficacy will be performed. The primary objective is to evaluate the local tolerability of daily application of AVX001 gel (1% or 3%) compared with vehicle gel. Secondary objectives include safety, efficacy, dose-response efficacy relationship, treatment satisfaction and cosmetic outcome. Exploratory objectives include evaluations of tolerability and efficacy assessed by dermatologists using smartphone photos uploaded by participants, comparisons of in-clinic and remote assessments and assessment of AK-related skin changes by non-invasive optical imaging.

ETHICS AND DISSEMINATION

Approved by the Ethics Committee of the Capital Region of Denmark (H-21018064) and the Danish Medicines Agency (2021032485). Results will be submitted for publication in peer-reviewed scientific journals.

TRIAL REGISTRATION NUMBERS

2021-000934-32; NCT05164393.

Ingol and Ingenol-Type Diterpenes from Euphorbia trigona Miller with Keratinocyte Inhibitory Activity

Ingenol mebutate, isolated from Euphorbia peplus, is an ingenane-type diterpenoid, primarily used for the topical treatment of actinic keratosis, a premalignant skin condition. The aim of our work was to investigate other Euphorbia species to find structurally similar diterpenes that can be used as alternatives to ingenol mebutate. Pharmacological investigation of Euphorbia candelabrum, Euphorbia cotinifolia, Euphorbia ramipressa, and Euphorbia trigona revealed the potent keratinocyte (HPV-Ker cell line) inhibitory activity of these spurge species. From the methanolic extract of the aerial parts of Euphorbia trigona Miller, the most active species, five ingol (1–5) and four ingenane-type diterpenoids (6–9) were isolated by various chromatographic separation techniques, including open column chromatography, vacuum liquid chromatography, thin-layer chromatography, and high-performance liquid chromatography. The structures of the compounds were determined by NMR spectroscopic analysis and by comparison of the assignations with the literature data. The cytotoxic activity of the compounds against keratinocytes was tested in vitro by using ingenol mebutate as a positive control. Among the isolated compounds, two ingenane derivatives (6 and 7) exhibited remarkably stronger cytotoxic activity (IC₅₀ values 0.39 μM and 0.32 μM, respectively) on keratinocytes than ingenol mebutate (IC₅₀ value 0.84 μM). These compounds could serve as starting materials for further investigations to find alternatives to Picato^® (with active substance ingenol mebutate), which was withdrawn from marketing authorization in the European Union.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

5-Fluorouracil Is Associated With a Decreased Recurrence Risk in Odontogenic Keratocyst Management: A Retrospective Cohort Study

PURPOSE

The antimetabolite drug, 5-fluorouracil (5-FU), has been suggested as an adjunctive treatment to reduce the recurrence rates of odontogenic keratocysts (OKCs). We report on the use of 5-FU in the management of patients with OKCs as a postenucleation intracavity topical dressing.

METHODS

For this retrospective cohort study, we collected all data of sequentially treated cases presenting to the University of Toronto's hospital clinics for the management of biopsy-proven OKCs. Chart reviews were conducted to identify all patients treated with 5-FU cream, and compare them to patients treated with modified Carnoy's solution (MCS). In the treatment group, all patients were treated in an identical manner with enucleation and peripheral ostectomy followed by the application of 5% 5-FU cream for 24 hours. Preoperative and postoperative radiographs were collected to determine the time to recurrence of the disease, and the techniques were compared via a multivariate Cox regression analysis.

RESULTS

Seventy patients were found to be eligible for inclusion in this study. Of these, 34 patients were treated with 5% topical 5-FU, and 36 patients were managed with MCS. The median follow-up time in the 5-FU group was 22 months (interquartile range, 36), compared with 27 months (interquartile range, 37) for the MCS group (P = .40). No recurrences were identified in the 5-FU group, compared with 9 recurrences (25%) in patients treated with MCS. 5-FU was shown to be significantly negatively associated with time to disease resolution (P < .01).

CONCLUSIONS

Results from this study suggest that when used topically, 5-FU effectively lowers the recurrence rates of OKCs. Further large scale, case-controlled studies are being investigated at our center and are warranted to make definitive conclusions regarding the effectiveness of this novel technique when compared with conventional therapies.

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

BACKGROUND

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

OBJECTIVES

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

MATERIAL AND METHODS

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

CONCLUSION

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

Identification of differentially expressed genes in actinic keratosis samples treated with ingenol mebutate gel

Actinic keratosis is a common skin disease that may progress to invasive squamous cell carcinoma if left untreated. Ingenol mebutate has demonstrated efficacy in field treatment of actinic keratosis. However, molecular mechanisms on ingenol mebutate response are not yet fully understood. In this study, we evaluated the gene expression profiles of actinic keratosis lesions before and after treatment with ingenol mebutate using microarray technology. Actinic keratoses on face/scalp of 15 immunocompetent patients were identified and evaluated after treatment with topical ingenol mebutate gel 0.015%, applied once daily for 3 consecutive days. Diagnostic and clearance of lesions was determined by clinical, dermoscopic, and reflectance confocal microscopy criteria. Lesional and non-lesional skin biopsies were subjected to gene expression analysis profiled by Affymetrix microarray. Differentially expressed genes were identified, and enrichment analyses were performed using STRING database. At 8 weeks post-treatment, 60% of patients responded to ingenol mebutate therapy, achieving complete clearance in 40% of cases. A total of 128 differentially expressed genes were identified following treatment, and downregulated genes (114 of 128) revealed changes in pathways important to epidermal development, keratinocyte differentiation and cornification. In responder patients, 388 downregulated genes (of 450 differentially expressed genes) were also involved in development/differentiation of the epidermis, and immune system-related pathways, such as cytokine and interleukin signaling. Cluster analysis revealed two relevant clusters showing upregulated profile patterns in pre-treatment actinic keratoses of responders, as compared to non-responders. Again, differentially expressed genes were mainly associated with cornification, keratinization and keratinocyte differentiation. Overall, the present study provides insight into the gene expression profile of actinic keratoses after treatment with ingenol mebutate, as well as identification of genetic signatures that could predict treatment response.

Nonablative fractional laser therapy for treatment of actinic keratosis with 3-months follow-up

BACKGROUND

Actinic keratosis (AK) is a common skin disorder that is treated with different treatment modalities.

AIMS

The aim of this study was to assess the therapeutic effect of a 1540-nm nonablative fractional laser on the AK.

METHODS

Ten patients with 31 AK were included in the study according to the inclusion and exclusion criteria. Treatment with nonablative fractional laser (1540 nm) 3 times at 4 weeks intervals in a noncontact mode was applied. Clinical severity was assessed at each session and 3 months after the last session. It is pertinent to mention that the patients were also involved in the assessment of improvement.

RESULTS

The results of present study showed that in comparison to the baseline, 3-session AK therapy with nonablative fractional laser significantly not only improved the AK severity by 79%, but also reduced the AK counts (from 31 to 17). On the other hand, the patients consented to the therapeutic effect.

CONCLUSION

According to the obtained results and available studies, it seems that therapy with a 1540-nm nonablative fractional laser could be considered as a safe and effective alternative therapeutic option for the treatment of AK.

Current therapies for actinic keratosis

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

Novel approaches for managing aged skin and nonmelanoma skin cancer

The process of aging influences every bodily organ and tissue, and those with rapid epithelial cell turnover, are particularly affected. The most visible of these, however, is the skin (including the epidermis), the largest human organ that provides a barrier to external insults, structure to the body and its movements, facilitates thermoregulation, harbors immune cells, and incorporates sensory neurons (including mechanoreceptors, nociceptors, and thermoreceptors). Skin aging has traditionally been categorized into intrinsic and extrinsic, with the latter nearly exclusively restricted to "photoaging," (i.e., aging due to exposure to solar or artificial ultraviolet radiation). However, both intrinsic and extrinsic aging share similar causes, including oxidative damage, telomere shortening, and mitochondrial senescence. Also, like other malignancies, the risk of malignant and nonmalignant lesions increases with age. Herein, we review the most recent findings in skin aging and nonmelanoma skin cancer, including addition to traditional and developing therapies.

Nanoparticles for topical drug delivery: Potential for skin cancer treatment

Nanoparticles offer new opportunities for the treatment of skin diseases. The barrier function of the skin poses a significant challenge for nanoparticles to permeate into the tissue, although the barrier is partially compromised in case of injury or inflammation, as in the case of skin cancer. This may facilitate the penetration of nanoparticles. Extensive research has gone into developing nanoparticles for topical delivery; however, relatively little progress has been made in translating them to the clinic for treating skin cancers. We summarize the types of skin cancers and practices in current clinical management. The review provides a comprehensive outlook of the various nanoparticle technologies tested for topical therapy of skin cancers and summarizes the obstacles that impede its progress from the bench-to-bedside. The review also aims to provide an understanding of the pathways that govern nanoparticle penetration into the skin and a critical analysis of the approaches used to study nanoparticle interactions within the tissue.

Split-Sided Chest Study of Skin Rejuvenation Comparing Low-Energy, 1,927-nm Thulium Fractional Laser Treatment Prior to Photodynamic Therapy Versus Photodynamic Therapy Alone

Background and Objectives

Treatment of photoaging and intrinsic aging of the chest, with the associated concerns of skin roughness, uneven pigmentation, laxity, atrophy, and telangiectasias, can be problematic because of the potential for worsened esthetic outcomes with existing treatments. This study assessed the efficacy and safety of using nonablative fractional laser therapy (FLT) pretreatment with photodynamic therapy (PDT) versus PDT alone for chest rejuvenation.

Study Design/Materials and Methods

In a randomized, evaluator‐blinded, split‐sided study, adult female patients with photodamage to the chest received three treatment courses over an 8‐week period with follow‐up visits at Weeks 12 and 20. FLT was applied to one side of the chest, randomly assigned at baseline, followed by aminolevulinic acid‐based PDT, delivered using a thermal, short incubation, broad area technique, to both sides of the chest. In‐person and photographic assessments were conducted using five‐point scales to evaluate outcomes including rhytides, pigmentation, skin texture, and telangiectasias.

Results

Eleven adults completed the study, of whom 11 had improved scores for rhytides and 10 had improved scores for skin texture at Week 20. There was no significant difference in any efficacy outcome between FLT and PDT and standard PDT alone. The severity of adverse events was rated significantly greater with the combined FLT–PDT treatment vs PDT alone.

Conclusions

Significant improvements were observed vs baseline for both sides of the chest treated with FLT–PDT or standard PDT following three treatment sessions. No significant difference in efficacy was observed between treatment approaches, although adverse events were more severe on the FLT‐pretreated side. This study was not registered as it qualified as a nonsignificant risk study. Lasers Surg. Med. © 2019 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

Clinical utility of daylight photodynamic therapy in the treatment of actinic keratosis - a review of the literature

Actinic keratosis (AK) is an early in situ squamous cell carcinoma that results from UV light exposure and has the potential to evolve into invasive tumor. Therefore, it is crucial that AKs are monitored and treated appropriately. Photodynamic therapy (PDT) is a treatment option that is minimally invasive and leaves patients with cosmetically superior results. However, disadvantages of PDT include pain and lengthy clinic visits. Accordingly, there has been much interest in the use of daylight photodynamic therapy (daylight-PDT) as a more convenient and less painful alternative to conventional photodynamic therapy (c-PDT). Current evidence shows that daylight-PDT is noninferior to c-PDT in the short and long term. Patients reported decreased pain with daylight-PDT and were more satisfied with the procedure (P<0.001). Current evidence suggests that 2 hrs of daylight exposure was sufficient for treatment, and its efficacy does not appear to be limited by weather conditions. Given the decreased intensity of treatment, daylight-PDT is better for mild disease, as it is less effective in moderate-to-thick AKs. Though further studies are still needed to refine the technique, daylight-PDT is a potential alternative to c-PDT for thin-to-moderate AKs and should be offered to patients with lower pain tolerance or busy schedules.

Mediators of Inflammation in Topical Therapy of Skin Cancers

Taking into consideration that the immune system plays a very important role in the development of melanoma and non-melanoma skin cancers, which have a high prevalence in immunosuppressed patients and after prolonged ultraviolet radiation, the interest in developing novel therapies, in particular targeting the inflammation in cancer, has increased in the past years. The latest data suggest that therapies such as imiquimod (IMQ), ingenol mebutate (IM), 5-fluorouracil (5-FU), retinoids, and nonsteroidal anti-inflammatory drugs (NSAIDs) have been used with success in the topical treatment of some cancers. Herein, we review the topical treatment targeting the inflammation in skin cancer and the mechanisms involved in these processes. Currently, various associations have shown a superior success rate than monotherapy, such as systemic acitretin and topical IMQ, topical 5-FU with tretinoin cream, or IMQ with checkpoint inhibitor cytotoxic T lymphocyte antigen 4. Novel therapies targeting Toll-like receptor-7 (TLR-7) with higher selectivity than IMQ are also of great interest.

Actinic keratosis - review for clinical practice

Actinic keratosis (AK) is a lesion that arises as a result of excessive exposure to solar radiation and appearing predominantly on Fitzpatrick phototype I and II skin. Given that some AKs evolve into squamous cell carcinoma, these lesions are considered premalignant in nature, occurring mostly in elderly men and immunosuppressed individuals chronically exposed to ultraviolet (UV) radiation. There are several mechanisms for the formation of AKs; among them are oxidative stress, immunosuppression, inflammation, altered proliferation and dysregulation of cell growth, impaired apoptosis, mutagenesis, and human papillomavirus (HPV). Through the understanding of these mechanisms, several treatments have emerged. Among the options for AK treatment, the most commonly used include 5-fluorouracil (5-FU), cryotherapy, diclofenac, photodynamic therapy (PDT), imiquimod (IQ), retinoids, and ingenol mebutate (IM). There have been recent advances in the treatment options that have seen the emergent use of newer agents such as resiquimod, betulinic acid, piroxicam, and dobesilate. The combination between therapies has presented relevant results with intention to reduce duration of therapy and side effects. All AK cases must be treated because of their propensity to transform into malignancy and further complicate treatment. In addition to medical or surgical care, education about sun exposure prevention remains the best and most cost-effective method for AK prevention. The objective of this article is to conduct a literature review of the clinical presentation of AK including advances in treatment options available.

Ingenol mebutate in the treatment of actinic keratoses: clearance rate and adverse effects

BACKGROUND

Actinic keratoses are benign intraepithelial skin neoplasms that develop in photoexposed areas and can progress to invasive carcinoma. They are seen frequently in dermatological practice, occurring in 5.1% of consultations. Ingenol mebutate (IM) was recently approved in Brazil as a topical therapy for field cancerization in actinic keratosis.

OBJECTIVE

To evaluate the clearance rate and adverse events in the treatment of actinic keratoses with ingenol mebutate.

METHODS

A longitudinal, prospective, non-randomized, interventional, open, single-center study was conducted. Patients with actinic keratoses applied ingenol mebutate on a 25cm2 area of the face and/or scalp for three consecutive days (0.015%) or on the forearm for two days (0.05%).

RESULTS

27 patients completed the protocol, of whom 13 on the face and/or scalp and 14 on the forearm. Complete clearance occurred in 53.8% in the first group and 42.8% in the second. Partial response was observed in 15.4% and 35.7%, respectively. The most common side effects were erythema, edema, desquamation, pruritus, and local erosion.

STUDY LIMITATIONS

The study had a small sample and was not randomized, double-blind, placebo-controlled, or vehicle-controlled.

CONCLUSION

Ingenol mebutate is well-tolerated for the treatment of actinic keratosis, with good patient adherence thanks to the short treatment period.

Successful Treatment of Actinic Keratosis with Kanuka Honey

Actinic keratoses form as rough, scaly plaques on sun-exposed areas; they can be an important step in premalignant progression to squamous cell cancer of the skin. Currently, pharmacological treatments consist of topical immunomodulatory agents with poor side effect profiles. Use of honey has been common in both ancient and modern medicine, where it is now a key therapy in the management of wound healing. In vitro studies show the New Zealand native Kanuka honey to have immunomodulatory and antimitotic effects, with recent evidence suggesting efficacy of topical application in a variety of dermatological contexts, including rosacea and psoriasis. Here, we present a case report of a 66-year-old gentleman with an actinic keratosis on his hand, which had been present for years. Regular application of Kanuka honey over three months resulted in remission immediately following the treatment period with no signs of recurrence at nine months.

A Rare Presentation of Actinic Keratosis Affecting the Tarsal Conjunctiva and Review of the Literature

We report an unusual case of actinic keratosis (AK) of the tarsal conjunctiva in a 63-year-old man. Examination revealed a crusty, leukoplakic lesion prone to bleeding on the tarsal conjunctiva of the right upper eyelid. This was treated by surgical excisional biopsy. At 1-year follow-up, there was no evidence of recurrence and the surgical site was completely healed without conjunctival scarring. Current opinion cites excessive exposure to ultraviolet (UV) radiation, in particular UV-B in sunlight, as the causative agent in developing AK. In the case we present, the tarsal conjunctiva is an unusual place for actinic keratosis due to the lack of direct UV-light exposure. The key learning points are to evert the upper eyelid during examination especially if the lesion involves the eyelid margin and, secondly, to ensure risk factors are addressed during the history.

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.

The effect of wool hydrolysates on squamous cell carcinoma cells in vitro. Possible implications for cancer treatment

Squamous cell carcinoma of the skin is the second most common cutaneous malignancy. Despite various available treatment methods and advances in noninvasive diagnostic techniques, the incidence of metastatic cutaneous squamous cell carcinoma is rising. Deficiency in effective preventive or treatment methods of transformed keratinocytes leads to necessity of searching for new anticancer agents. The present study aims to evaluate the possibility of using wool hydrolysates as such agents. Commercially available compounds such as 5-fluorouracil, ingenol mebutate, diclofenac sodium salt were also used in this study. The process of wool degradation was based on chemical pre-activation and enzymatic digestion of wool. The effect of mentioned compounds on cell viability of squamous carcinoma cell line and healthy keratinocytes was evaluated. The obtained data show a significantly stronger effect of selected wool hydrolysates compared to commercial compounds (p<0.05) on viability of cells. The wool hydrolysates decreased squamous cell carcinoma cells viability by up to 67% comparing to untreated cells. These results indicate bioactive properties of wool hydrolysates, which affect the viability of squamous carcinoma cells and decrease their number. We hypothesize that these agents may be used topically for treatment of transformed keratinocytes in actinic keratosis and invasive squamous skin cancer in humans.

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

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

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

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

Diagnosis of actinic keratosis by dermatoscopy

Introduction: Actinic keratosis (AK) is a local introepidermal atypia of keratinocytes, formed as a result of intense and prolonged exposure to sunlight. AK lesions located on exposed areas of skin, mostly on the face, in this regard, a more relevant non-invasive diagnostic techniques, primarily dermatoscopy. Material and methods: We examined 35 patients and revealed they have 204 hearth. Results: Of the 204 lesions erythematous form was found in 160 (78, 4%) cases, keratotic - 24 (11,8%), pigmental (9.8 %). Patients with AK most private dermatoscopic signs were erythema (90,2%), vascular structures (67,65%), keratin scales (51,47%), pseudonetwork (23,04%). Discussion: Analyzing dermoscopic picture of the most common forms of AK met the characteristics for each shape. A detailed study of vascular structures allows for the differential diagnosis of cancer in situ. While AK watched point and the glomerular vessels of not more than 10% of cases, which helped to differentiate AK from cancer in situ, in which such vessels were found in 40%. Glomerular vessels are not met in our study and the points were only 2.45% of the cases. Keratotic AK was characterized in 100% of cases the presence of keratin scales. In pigment form, we revealed the dark brown streaks (80%), dark brown points (50%), brown globules (30%), dark brown blots (10%) and slate-grey dots (10%). But the gold standard for the differential diagnosis with maligna lentigo is a morphological study. Conclusion: AK has specific characteristics in treatment research, which helps to differentiate it from other benign and malignant tumors of the skin, and to diagnose it in its earliest stages without resorting to invasive procedures. Effective diagnosis of AK reduces the risk of malignant transformation and contribute to the selection of adequate and necessary treatment tactics.

Structured Expert Consensus on Actinic Keratosis: Treatment Algorithm Focusing on Daylight PDT

Background:

A practical and up-to-date consensus among experts is paramount to further improve patient care in actinic keratosis (AK).

Objectives:

To develop a structured consensus statement on the diagnosis, classification, and practical management of AK based on up-to-date information.

Methods:

A systematic review of AK clinical guidelines was conducted. This informed the preparation of a 3-round Delphi procedure followed by a consensus meeting, which combined the opinions of 16 clinical experts from 13 countries, to construct a structured consensus statement and a treatment algorithm positioning daylight photodynamic therapy (dl-PDT) among other AK treatment options.

Results:

The systematic review found deficiencies in current guidelines with respect to new AK treatments such as ingenol mebutate and dl-PDT. The Delphi panel established consensus statements across definition, diagnosis, classification, and management of AK. While the diagnosis of AK essentially rests on the nature of lesions, treatment decisions are based on several clinical and nonclinical patient factors and diverse environmental attributes. Participants agreed on ranked treatment preferences for the management of AK and on classifying AK in 3 clinical situations: isolated AK lesions requiring lesion-directed treatment, multiple lesions within a small field, and multiple lesions within a large field, both requiring specific treatment approaches. Different AK treatment options were discussed for each clinical situation.

Conclusions:

The results provide practical recommendations for the treatment of AK, which are readily transferable to clinical practice, and incorporate the physician’s clinical judgement. The structured consensus statement positioned dl-PDT as a valuable option for patients with multiple AKs in small or large fields.

Efficacy of ingenol mebutate gel for actinic keratosis in patients treated by thiazide diuretics

Actinic keratosis (AK) is considered as superficial squamous cell carcinoma. Chronic sun exposure plays a central role in its pathogenesis. In particular, ultraviolet B radiation causes direct damage to the DNA, producing pyrimidine dimers that suppress the protective role of p53. Other risk factors include advanced age, male sex, and fair skin type. Even some drugs used for treating blood hypertension, such as thiazide diuretics, can increase the risk of developing AK. Their photosensitizing action seems to be connected with reactive oxygen species production. We report our experience with ten patients affected by multiple AK, in therapy with thiazide diuretics, treated by ingenol mebutate gel. AK was clinically and dermoscopically evaluated at baseline and after 30 days from the beginning of the treatment. Moreover, patients were screened for vitamin D₃ values and reported a general hypovitaminosis status. To our knowledge, we report for the first time the efficacy of ingenol mebutate gel in this group of patients, particularly at risk of developing AK.

PDT and emerging therapies for Actinic Keratosis-A resource letter

Aktinic Keratosis is common and if left untreated may develop into life threatening squamous cell carcinoma. Therefore early intervention is the standard of care. While many treatments are available PDT continues to move to the for - front for this indication (Brito et al., 2016 [31]). Topical PS is commercially available that are able to reliably ablate these lesions. Innovative protocols including sunlight, large volume LED arrays and maneuvers to improve treatment parameters and cosmesis continue to make this a worldwide treatment of choice for AK.

Actinic keratosis and field cancerization

While actinic keratoses (AKs) have been considered precancerous until recently for being able to turn into squamous cell carcinomas (SCCs), it is now agreed that it would be more appropriate to call them cancerous. Although not all AKs turn into SCC and some of them may even have a spontaneous regression, there is an obvious association between SCC and AK. Approximately 90% of SCs have been reported to develop from AKs and AKs are the preinvasive form of SCCs. The presence of two or more AKs on a photodamaged skin is an indicator of field cancerization and represents an increased risk of invasive SCC. All lesions should be treated since it cannot be foreseen which of the lesions will regress and which will progress to SCC. AK can be a single lesion or it can involve multiple lesions in a field of cancerization; thus, AK treatment is grouped under two headings: (1) Lesion-specific treatment; and (2) Field-targeted treatment. Lesion-specific treatments are practicable in patients with a small number of clinically visible and isolated lesions. These treatments including cryotherapy, surgical excision, shave excision, curettage and laser are based on physical destruction of the visible lesions. Field-targeted treatments are effective in the treatment of visible lesions, subclinical lesions and keratinocyte changes in the areas surrounding the visible lesions. Field targeted treatment options are topical imiquimod cream, 5% 5-fluorouracil cream, ingenol mebutate, diclofenac gel, resimiquimod and photodynamic therapy.