Defining the actinic keratosis field: a literature review and discussion

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

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

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

A Novel Actinic Keratosis Field Assessment Scale for Grading Actinic Keratosis Disease Severity

Actinic keratosis (AK) lesions are surrounded by field cancerization (areas of subclinical, non-visible sun damage). Existing AK grading tools rely on AK counts, which are not reproducible. An Actinic Keratosis Field Assessment Scale (AK-FAS) for grading the severity of AK/field was developed. Standardized photographs of patients representing the full range of AK severity were collected. Six investigators independently rated each photograph according to 3 criteria: AK area (total skin area affected by AK lesions), hyperkeratosis and sun damage. Inter-rater reproducibility was good for all 3 criteria. Validation of the AK-FAS showed good reproducibility for AK area and hyperkeratosis, even for dermatologists untrained on use of the scale. In conclusion, the AK-FAS is objective, easy to use and implement, and reproducible. It incorporates assessment of the entire field affected by AK instead of relying on lesion counts. Use of the AK-FAS may standardize AK diagnosis, making it relevant to routine clinical practice.

Acantholytic dermatosis of the vagina: the diagnostic challenge of acantholytic disease in the genital region

We report the case of a 24-year-old woman with an 8-month history of deep pelvic pain and postcoital bleeding. Examination revealed desquamation of the vaginal epithelium with tender fissured plaques in the vagina, initially thought to be vaginal intraepithelial neoplasia. Histology showed squamous mucosa with suprabasal acantholysis and hyperkeratosis, and no evidence of viral infection, dysplasia or malignancy. These findings were consistent with acantholytic dermatosis (AD), a rare lesion that resembles Hailey-Hailey and Darier disease histopathologically, but can be distinguished on a clinical basis. Vulval cases of AD are well recognized, but to our knowledge, this is the first reported case involving the vaginal epithelium alone.

Suppression of TGFβ and Angiogenesis by Type VII Collagen in Cutaneous SCC

BACKGROUND

Individuals with severe generalized recessive dystrophic epidermolysis bullosa (RDEB), an inherited blistering disorder caused by mutations in the COL7A1 gene, develop unexplained aggressive squamous cell carcinomas (SCC). Here we report that loss of type VII collagen (Col7) in SCC results in increased TGFβ signaling and angiogenesis in vitro and in vivo.

METHODS

Stable knockdown (KD) of Col7 was established using shRNA, and cells were used in a mouse xenograft model. Angiogenesis was assessed by immunohistochemistry, endothelial tube-forming assays, and proteome arrays. Mouse and zebrafish models were used to examine the effect of recombinant Col7 on angiogenesis. Findings were confirmed in anonymized, archival human tissue: RDEB SCC tumors, non-EB SCC tumors, RDEB skin, normal skin; and two human RDEB SCC cell lines. The TGFβ pathway was examined using immunoblotting, immunohistochemistry, biochemical inhibition, and siRNA. All statistical tests were two-sided.

RESULTS

Increased numbers of cross-cut blood vessels were observed in Col7 KD compared with control xenografts (n = 4 to 7 per group) and in RDEB tumors (n = 21) compared with sporadic SCC (n = 24, P < .001). Recombinant human Col7 reversed the increased SCC angiogenesis in Col7 KD xenografts in vivo (n = 7 per group, P = .04). Blocking the interaction between α2β1 integrin and Col7 increased TGFB1 mRNA expression 1.8-fold and p-Smad2 levels two-fold. Increased TGFβ signaling and VEGF expression were observed in Col7 KD xenografts (n = 4) compared with control (n = 4) and RDEB tumors (TGFβ markers, n = 6; VEGF, n = 17) compared with sporadic SCC (TGFβ markers, n = 6; VEGF, n = 21). Inhibition of TGFβ receptor signaling using siRNA resulted in decreased endothelial cell tube formation (n = 9 per group, mean tubes per well siC = 63.6, SD = 17.1; mean tubes per well siTβRII = 29.7, SD = 6.1, P = .02).

CONCLUSIONS

Type VII collagen suppresses TGFβ signaling and angiogenesis in cutaneous SCC. Patients with RDEB SCC may benefit from anti-angiogenic therapy.

Successful treatment of a patient with severe atopic dermatitis and severe asthma by centrifugal therapeutic plasma exchange

This is a case of a 42-year-old atopic man with severe atopic dermatitis and asthma who despite long-term immunosuppression was not well controlled. He had a very high IgE at 7897 Iu/mL prior to treatment. He underwent two therapeutic plasma exchanges (TPEs) through two peripheral lines in our outpatient department, which led to an absolute decrease of 44.1% and 37% in his plasma IgE for each exchange, and immediate sustained improvement in shortness of breath, and atopic dermatitis, and hence led to a vast improvement in his quality of life. TPE offers a new exciting adjunctive treatment option for severe atopic individuals, where it may provide a novel role to reduce health burden and improve clinical symptoms. Further studies need to be performed to establish an optimal protocol and potential maintenance with recently available targeted anti-IgE biologics.

A consensus approach to improving patient adherence and persistence with topical treatment for actinic keratosis

BACKGROUND

Topical therapy is important in the treatment of actinic keratosis, but guidance for improving adherence/persistence during topical therapy is still lacking.

OBJECTIVES

To utilize expert consensus to generate a list of recommendations to improve real-world efficacy when prescribing topical therapy for actinic keratosis.

METHODS

An expert panel of eight dermatologists was convened to generate recommendations based on facilitated discussion and consensus generation using a modified Delphi session. The recommendations were ratified with the expert panel.

RESULTS

Facilitated discussion generated 31 issues within five themes, which were prioritized using expert voting. Consensus was achieved on the importance of short and simple treatment regimens for maximizing patient compliance, physician awareness of the progression of actinic keratosis to squamous cell carcinoma, provision of appropriate patient information, and the use of effective communication strategies to educate physicians about actinic keratosis. Based on these key findings, eight recommendations were generated.

CONCLUSIONS

The recommendations will assist physicians when prescribing topical actinic keratosis therapy. Further research should focus on the types of patient outcomes that are influenced by the characteristics of topical field therapy.

A consensus approach to improving patient adherence and persistence with topical treatment for actinic keratosis

BACKGROUND

Topical therapy is important in the treatment of actinic keratosis, but guidance for improving adherence/persistence during topical therapy is still lacking.

OBJECTIVES

To utilize expert consensus to generate a list of recommendations to improve real-world efficacy when prescribing topical therapy for actinic keratosis.

METHODS

An expert panel of eight dermatologists was convened to generate recommendations based on facilitated discussion and consensus generation using a modified Delphi session. The recommendations were ratified with the expert panel.

RESULTS

Facilitated discussion generated 31 issues within five themes, which were prioritized using expert voting. Consensus was achieved on the importance of short and simple treatment regimens for maximizing patient compliance, physician awareness of the progression of actinic keratosis to squamous cell carcinoma, provision of appropriate patient information, and the use of effective communication strategies to educate physicians about actinic keratosis. Based on these key findings, eight recommendations were generated.

CONCLUSIONS

The recommendations will assist physicians when prescribing topical actinic keratosis therapy. Further research should focus on the types of patient outcomes that are influenced by the characteristics of topical field therapy.

Key differences identified between actinic keratosis and cutaneous squamous cell carcinoma by transcriptome profiling

Background:

Cutaneous squamous cell carcinoma (cSCC) is one of the most common malignancies in fair-skinned populations worldwide and its incidence is increasing. Despite previous observations of multiple genetic abnormalities in cSCC, the oncogenic process remains elusive. The purpose of this study was to elucidate key molecular events associated with progression from premalignant actinic keratoses (AKs) to invasive cSCC by transcriptome profiling.

Methods:

We combined laser capture microdissection with the Affymetrix HGU133 Plus 2.0 microarrays to profile 30 cSCC and 10 AKs.

Results:

We identified a core set of 196 genes that are differentially expressed between AK and cSCC, and are enriched for processes including epidermal differentiation, cell migration, cell-cycle regulation and metabolism. Gene set enrichment analysis highlighted a key role for the mitogen activated protein kinase (MAPK) pathway in cSCC compared with AK. Furthermore, the histological subtype of the tumour was shown to influence the expression profile.

Conclusion:

These data indicate that the MAPK pathway may be pivotal to the transition from AK to cSCC, thus representing a potential target for cSCC prevention. In addition, transcriptome differences identified between cSCC subtypes have important implications for future development of targeted therapies for this malignancy.

Prospective study of sentinel lymph node biopsy for conjunctival melanoma

BACKGROUND

To report our experience with sentinel lymph node biopsy for staging patients with conjunctival melanoma.

METHODS

A prospective review of patients with conjunctival melanoma who underwent sentinel lymph node biopsy at St Bartholomew's Hospital from May 2008 to May 2012. The selection criterion for sentinel node biopsy depended on the tumour thickness (≥2 mm) and location of the conjunctival melanoma. The main outcome measures were the incidence of sentinel lymph node positivity and the procedure-related complications.

RESULTS

In 4 years, 26 out of 70 patients met the selection criteria for sentinel lymph node biopsy. 4 patients declined and 22 patients consented for the procedure. Technetium-99m failed to identify a sentinel lymph node in four of the 22 patients (18%). Of the remaining 18 patients, two were found to have subclinical micrometastasis in regional lymph nodes. Median follow-up was 20 months (range 6-36 months). No false-negative events were observed. Complications of the procedure included transient blue staining of the epibulbar surface in five patients and transient facial nerve palsy in one patient.

CONCLUSIONS

Sentinel lymph node biopsy is a safe procedure with minimal complications. It should be considered for the staging of conjunctival melanomas, especially melanomas in non-limbal location or conjunctival melanomas ≥2 mm thick.