Invited Speakers Abstracts
Department Dermatology, Division General Dermatology, Medical University Vienna, Vienna, Austria
Actinic keratoses (AKs) are regarded as early squamous cell carcinomas (SCCs) in situ that most commonly develop in populations with skin photo type I-II with an overall increase in the AK prevalence worldwide in recent decades. It is now widely accepted that AKs develop through a multistep process termed ‘field cancerization’ which is induced by solar exposure and culminates in the development of squamous cell carcinomas (SCCs). Because of the substantial risk of the progression of AKs to invasive SCCs and the propensity in patients to develop new lesions over time, current guidelines recommend active treatment of all AK lesions. Within the last decade the armamentarium of dermatologists for the treatment of AKs has largely expanded. A novel and attractive treatment option represents 3% diclophenac in 2.5% hyaluronic acid gel (Solaraze). Diclofenac is a widely used and well accepted NSAID used orally as well as topically to treat inflammation and pain. The combination of Diclofenac with hyaluronic acid in Solaraze leads to improved drug delivery to the skin and targets specific pathways involved in tumor development. Solaraze inhibits Cyclooxygenase (COX-2) activity and thus the production of prostaglandin E2 (PGE2). This induces a slowdown of the proliferation of malignant keratinocytes. Through the reduction of PGE2 synthesis Solaraze induces apoptosis in malignant cells, down regulates inflammation, inhibits angiogenesis and activation of the mitochondrial apoptosis pathways.
A number of placebo-controlled and open label clinical studies have demonstrated that twice daily treatment with Solaraze results in marked regression of actinic lesions, with a significant proportion of patients experiencing complete resolution of their AKs. The lesion clearance increases with the length of treatment. Best results are reported for a treatment period of 90 days followed by an observation time of 30 days. Clinical studies reveal persistent good lesion clearance of 50% for up to one year after treatment cessation and clinical improvement in up to 80%. Very recently, a clinical study in organ-transplant patients demonstrated reduction of AKs by 53% whereas lesions increased under placebo by 17%. Clearance of AKs was coupled with good tolerability in high-risk organ-transplant patients.
The overall adverse reactions reported in clinical trials with Solaraze were predominantly skin-related and mild to moderate in nature. The most frequently reported side effects were pruritus and dry skin.
With its favorable clinical efficacy and tolerability profile Solaraze is an attractive and innovative therapeutic option for the topical treatment of AKs.