Valutazione clinica, dermatoscopica e istologica di cheratosi attiniche non responsive a terapie

Actinic keratoses (AKs), also known as solar keratosis or keratinocytic intraepidermal neoplasia, are the most common neoplasms within the continuum of keratinocyte skin cancer. Although AKs have been historically defined as “precancerous” or “premalignant,” more recent histopathologic and molecular studies support their current classification as earliest stage of squamous cell carcinoma (SCC) in situ. Prevalence estimates of AK range between 1% and 44% in the adult population. Skin type and cumulative sunlight exposure are major risk factors for both AK and SCC. Once developed, AK may follow one of three different pathways: regression, persistence, or progression to in situ or invasive SCC. Although the actual risk of an individual AK progressing to invasive SCC is unclear, estimations vary from as low as 0.1% to as high as 20%. Various study in literature have considered the clinical and histological aspect of AK but in particular no author has ever classified clinical, dermoscopical and histological peculiar features of non-responder AK. Our project want to follow up the non-responder AK to understand if there are some characteristics than can predict this comportment and the potential evolution versus SCC. The main objective is evaluated the histological feature of AK (single or on field cancerization) that not responder at least two specific treatment including cryosurgery, Ingenol Mebutate, imiquimod, PDT, diclofenac 3% and 5% fluorouracile. In addition to the primary objective, we will consider the following items: clinical feature of non-responder AK; videodermatoscopy aspect of non-responder AK and we evaluate, if possible, the risk of an individual non responder AK progressing to invasive SCC.