Acta Dermato-Venereologica Issue 8, 2017 97-8CompleteContent | Page 34

CORRESPONDENCE Controversies in Dermatology 997 Actinic Keratosis, a Chronic, Progressive Disease: Understanding Clinical Gaps to Optimise Patient Management Rino CERIO 1 , Thomas DIRSCHKA 2 , Brigitte DRÉNO 3 , Ignasi FIGUERAS NART 4 , John T. LEAR 5 , Giovanni PELLACANI 6 , Ketty PERIS 7 , Andrés RUIZ DE CASAS 8 (PEAK Working Group*) 1 Department of Cutaneous Medicine and Surgery, 2 nd Floor South Tower, The Royal London Hospital and QMUL, Bart’s Health NHS Trust, Whitechapel, London E1 1BB, UK, 2 CentroDerm ® clinic, Wuppertal, and Faculty of Health, University Witten-Herdecke, Witten, Germany, 3 Department of Dermato Cancerology, University of Nantes, Nantes, France, 4 Department of Dermatology, Bellvitge Hospital, Barcelona, Spain, 5 Manchester Academic Health Science Centre, MAHSC, Manchester University and Salford Royal NHS Foundation Trust, Royal Infirmary, The University of Manchester, Manchester, UK, 6 Department of Dermatology, University of Modena and Reggio Emilia, Modena, 7 Department of Dermatology, Catholic University of Rome, Rome, Italy, and 8 Dermatology Unit, Virgen Macarena University Hospital, Seville, Spain. E-mail: [email protected] Accepted Apr 27, 2017; Epub ahead of print Apr 27, 2017 Actinic keratosis (AK) is a chronic, progressive disease of the skin that has undergone long-term sun exposure. The affected areas contain visible and subclinical non- visible sun damage resulting in epidermal keratinocyte dysplasia, known by many as ‘field cancerisation’ (1), which is prone to AKs and sun-related skin cancer (2). Thus, visible AKs are clinical biomarkers for a photo-da- maged field with subclinical damage associated with the unpredictable risk of progression to invasive squamous cell carcinoma (iSCC) (3). The aim of this multiexpert opinion article is to provide a discussion succinctly highlighting the clinical gaps for optimal management of AK: the lack of a universal definition and the need for a standardised grade assessment of AK/field cancerisation that also takes into account individual risk. The prevalence of AK varies from 6–60%, depen- ding on age, phototype and other predisposing risk factors (most notably immunosuppressed status, out- door workers), and is increasing (1, 4), with a parallel increase in non-melanoma skin cancer (NMSC). AK presents a considerable socioeconomic burden, which will inevitably increase with an aging population (1, 4). To minimise this burden, AK should be recognised and treated, particularly in populations at high risk of NMSC. The goal of therapy should be to eliminate AK/ field cancerisation (visible and non-visible subclinical lesions) to minimise risk of AK recurrence and potential progression to iSCC (5), although evidence for the lat- ter is lacking. Some authors in specialised centres have shown the additional value of imaging methods in such management, particularly in visualising the evolution of subclinical lesions, which can be a challenge in current clinical practice (2). Lesion-directed therapy (e.g. cryotherapy), treats only visible AKs, so field–directed treatment is necessary to treat subclinical damage, reduce AK recurrence rates and potentially minimise the risk of iSCC development (5). Recent guidelines recognise the importance of trea- ting the entire field (5–7). However, cryotherapy alone *The Progressing Evidence in AK (PEAK) Working Group, formed to identify and address existing educational needs in AK remains the standard of care for treating AK patients with multiple lesions. This suggests that education, and growing evidence that treating the field is equally as important as treating visible AKs, will be instrumental in reducing the increasing disease burden. Shifting the treatment paradigm will require understanding the clini- cal gaps that need addressing. Firstly, there is a need for a standardised definition of AK field cancerisation in clinical, molecular and histo- pathological terms. Current guidelines define field can- cerisation based on number of AK lesions and presence of surrounding photo-damaged skin (5–7). However, there are wide discrepancies within these criteria (Table I). Moreover, experts have voiced concerns over using a definition based on AK counts, as existing evidence suggests that any AK should be considered a marker of field change (8). A clearer and unambiguous definition of field cancerisation that is standardised and reprodu- cible is required to support diagnosis and management, including treatment options and identification of ‘red flag’ signs of high-risk tumours. Physicians can only manage field cancerisation appropriately if they understand its characteristics and severity. A second clinical gap is the lack of a reproducible clinical global assessment scale for grading AK/field can- cerisation. Current guidelines assess only the presence or absence of AK/field cancerisation, without a severity grading. A global assessment scale should include a clini- cal description of the key characteristics for each grade of severity to guide effectively identification, diagnosis and treatment decisions. This clinical grading should be considered alongside modulating risk factors: • age • skin phototype • lifestyle • occupation • geographical location • history of skin cancer • immunosuppression. Through clinical grading based on disease severity and individual patient risk factors, a therapeutic algorithm This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Journal Compilation © 2017 Acta Dermato-Venereologica. doi: 10.2340/00015555-2692 Acta Derm Venereol 2017; 97: 997–998