Two cases of disseminated superficial actinic porokeratosis treated with daylight-mediated photodynamic therapy

Porokeratoses-A Comprehensive Review on the Genetics and Metabolomics, Imaging Methods and Management of Common Clinical Variants

Porokeratosis is a heterogeneous group of keratinising disorders characterised by the presence of particular microscopic structural changes, namely the presence of the cornoid lamella. This structure develops as a consequence of a defective isoprenoid pathway, critical for cholesterol synthesis. Commonly recognised variants include disseminated superficial actinic porokeratosis, disseminated superficial porokeratosis, porokeratosis of Mibelli, palmoplantar porokeratosis (including porokeratosis palmaris et plantaris disseminata and punctate porokeratosis), linear porokeratosis, verrucous porokeratosis (also known as genitogluteal porokeratosis), follicular porokeratosis and porokeratoma. Apart from the clinical presentation and epidemiology of each variant listed, this review aims at providing up-to-date information on the precise genetic background, introduces imaging methods facilitating the diagnosis (conventional and ultraviolet-induced fluorescence dermatoscopy, reflectance confocal microscopy and pathology), discusses their oncogenic potential and reviews the literature data on the efficacy of the treatment used, including the drugs directly targeting the isoprenoid-mevalonate pathway.

Effective treatment of disseminated superficial actinic porokeratosis with chemical peels - customary treatment for a rare disease

Background: Disseminated superficial actinic porokeratosis (DSAP) is a rare dermatologic disorder of the epidermis. Often misdiagnosed as chronic UV-damage or actinic keratoses, patients are treated for years with different therapeutic options with little success. Current treatment options include imiquimod, ingenol mebutate, cryosurgery, photodynamic therapy and topical or systemic therapy with retinoids. Since those approaches show only little success or come along with major side effects, therapeutic alternatives are strongly requested. Methods: We report a series of five female patients with history of DSAP that were successfully treated with chemical peels. Results: All patients suffered from the disease for 14.4 years on average and all were refractory to at least two therapeutic options, mostly imiquimod and topical tretinoin. Patients were treated with glycolic acid 50% and salicylic acid 25% in a two-layer-technique. After a mean of three cycles every 6 weeks a clear reduction in lesion was assessed by physicians. Patients were highly satisfied with outcome and rare occurrence of side effects as assessed by TSQM questionnaire. Conclusion: Chemical peels are safe and well tolerated treatment options for patients with refractory porokeratosis. As characteristic for chronic diseases, frequent repetition of treatment is needed in order to control disease activity.

Treatment of Porokeratosis: A Systematic Review

BACKGROUND

Porokeratosis (PK) is a rare skin disease of unknown etiology. It consists of a keratinization disorder, which may appear in several clinical forms and can undergo malignant transformation. The histopathological hallmark of PK is the cornoid lamella. While many topical, systemic, and surgical treatment modalities for PK have been described, no randomized controlled trials have been performed yet. Because of a lack of treatment standards for PK, European and international guidelines cannot be created.

OBJECTIVE

The aim of this systematic review is to outline options for treating PK.

METHODS

We performed a systematic literature search in an electronic database for published literature. A total of 88 articles fulfilling our inclusion criteria were found.

RESULTS

There were no randomized controlled trials on the treatment of PK, but mainly case reports and case series. Porokeratosis of Mibelli showed the best outcomes after treatment with imiquimod cream and linear PK responded well to topical or systemic retinoids. Topical vitamin D acid derivatives may be the best therapeutic option for disseminated PK. Surgical interventions and cryotherapy may be preferred in areas where the use of topical agents is difficult or contraindicated.

CONCLUSION

To offer patients with PK an evidence-based high-quality standardized therapy, randomized controlled trials are needed.