Evaluation of ammonium lactate in the treatment of seborrheic keratoses

Efficacy and safety of topical treatments for seborrheic keratoses: a systematic review

Seborrheic keratoses (SKs) are benign epidermal neoplasms presenting as waxy, brown to black papules and plaques. Patients often seek removal for cosmetic reasons or irritation. The objective of this systematic review is to assess the efficacy and safety of topical treatments for SKs. Studies involving any topical medication indicated for SK removal were retrieved from Embase, Scopus, PubMed, and Cochrane. The final search was conducted on November 9, 2021, and 26 reports met inclusion criteria. A quality rating scheme was utilized to assess evidence quality. Heterogeneity of treatments and outcome measures precluded meta-analysis. Topical treatments that yielded a good-to-excellent response include hydrogen peroxide, Maxacalcitol 25 µg/g, BID Tazarotene 0.1% cream, 5% potassium dobesilate cream, 1% diclofenac sodium solution, urea-based solution, and 65% and 80% trichloroacetic acid. Local skin reactions were often mild and transient. Topical hydrogen peroxide showed the greatest evidence for clinical clearance of SKs, although there are no studies to our knowledge that directly compared hydrogen peroxide to current first-line treatments (e.g. cryotherapy or shave excision). The results of this review suggest viable and safe treatment of SK with topical therapies; however, there remains demand for topical treatments that reliably equate or exceed the efficacy of current first-line therapies.Key PointsQuestion: Are safe and efficacious topical treatments for seborrheic keratoses available?Findings: Topical treatments for seborrheic keratoses yield different responses and may be associated with local skin reactions. Topical hydrogen peroxide shows the greatest evidence for clinical clearance of seborrheic keratoses and may be a viable option for patients requesting noninvasive removal. No studies to our knowledge directly compare hydrogen peroxide to current first-line treatments.Meaning: There remains demand for topical treatments that reliably equate or exceed the efficacy of current first-line therapies.

Update of pathophysiology and treatment options of seborrheic keratosis

Seborrheic keratosis (SK) is a common, benign tumor that can occur on everybody site and can be conservatively managed. Cosmetic concerns, especially when a lesion involves the facial area, are the most common reason for excision. SK shows male gender preponderance and increasing age is an independent association with the condition. Even though more prevalent in the elderly, it has also been reported in younger age groups like adolescents and young adults. Precise pathogenesis is still obscure, but ultra-violet exposure represents a predisposing factor to SK by altering the biochemical concentration and expression of factors like Glutamine deaminases, endothelin, and stem cell factor. Moreover, the accumulation of amyloid-associated protein has also been postulated. Involvement of genitalia has been associated with human papillomavirus infection. Recently, Merkel cell polyomavirus nucleic acid was also detected in SK. Several oncogenic mutations involving FGFR-3 and FOXN1 have been identified. SKs are usually classified clinically and histologically. Dermatoscopy is a noninvasive alternative diagnostic technique widely used in differentiating SK from other benign and malignant tumors. In terms of treatment, topical agents, shave dissection, cryosurgery, electrodesiccation, laser application and curettage under local anesthesia are safe methods for eradication of SKs, mostly for cosmetic purposes. Though generally safe, the latter techniques may occasionally cause post-procedure depigmentation, scarring, and recurrence. Nanosecond-pulsed electric field technology is a promising new technique with fewer side-effects.

Advances in the Etiology, Detection, and Clinical Management of Seborrheic Keratoses

Seborrheic keratoses (SKs) are ubiquitous, generally benign skin tumors that exhibit high clinical variability. While age is a known risk factor, the precise roles of UV exposure and immune abnormalities are currently unclear. The underlying mechanisms of this benign disorder are paradoxically driven by oncogenic mutations and may have profound implications for our understanding of the malignant state. Advances in molecular pathogenesis suggest that inhibition of Akt and APP, as well as existing treatments for skin cancer, may have therapeutic potential in SK. Dermoscopic criteria have also become increasingly important to the accurate detection of SK, and other noninvasive diagnostic methods, such as reflectance confocal microscopy and optical coherence tomography, are rapidly developing. Given their ability to mimic malignant tumors, SK cases are often used to train artificial intelligence-based algorithms in the computerized detection of skin disease. These technologies are becoming increasingly accurate and have the potential to significantly augment clinical practice. Current treatment options for SK cause discomfort and can lead to adverse post-treatment effects, especially in skin of color. In light of the discontinuation of ESKATA in late 2019, promising alternatives, such as nitric-zinc and trichloroacetic acid topicals, should be further developed. There is also a need for larger, head-to-head trials of emerging laser therapies to ensure that future treatment standards address diverse patient needs.

Management of skin adverse reactions in oncology

Chemo and targeted anticancer therapies present significant skin adverse reactions, which impair the patients' quality of life. Cutaneous toxicities lead to poor treatment adherence, drug cessation, and psychosocial distress. This review aims to summarize the current knowledge concerning the prevention and management of skin toxicity arising from these therapies. A systematic literature search on online databases was conducted. The categorization of the main preventive and treatment measures was performed according to the level of evidence. Management of skin adverse reactions of oncology treatments is very heterogeneous, which can be explained by the lack of sound evidence-based treatments. The most studied adverse effects are papulopustular eruption, xerosis, and hand-foot syndrome. Prevention of xerosis stands out as the strategy most supported by level II studies. With respect to treatment, the use of antibiotics in papulopustular eruption resulting from anti-epidermal growth factor receptor agents is the most evidence-based approach. In general, the number of studies published in the literature classified with a level II of evidence (52%) is similar to the ones classified as level IV (33%), making clear the need of more randomized controlled trials regarding the effectiveness of preventive and treatment measures of skin adverse reactions of chemo and targeted anticancer therapies.

Assessment of in vitro percutaneous absorption of glycolic acid through human skin sections using a flow-through diffusion cell system

The percutaneous absorption studies were performed using a flow-through diffusion cell system with skin specimens from 24 healthy women to assess the penetration of glycolic acid (GA). Percentages of GA, based on 14C-labelled activity, found in the skin after application of 4% GA at pH 2.0 or pH 3.8, after 24 h were as follows: stratum corneum (SC)= 2.65+/-1.80 versus 1.13+/-1.14 (P<0.05); viable skin (VS)= 13.46+/-7.44 versus 2.23+/-1.51 (P< 0.05) and effluent fraction (EF) = 12.22+/-9.03 versus 1.42+/-0.77 (P < 0.05), respectively. The applications of 4-60%, GA at their native pH resulted in an increased penetration of GA through the skin. For example, application of 20% GA, pH 1.9, resulted in the following values: SC = 2.69+/-2.26 (P > 0.05); VS = 4.88+/-4.05 (P > 0.05) and EF = 30.69+/-13.25 (P < 0.05). Duration of application also affected the extent of penetration of drug. For example, application of 20% GA, pH 1.9, for 6 h resulted in the following levels: SC = 1.16+/-0.80 (P < 0.05); VS = 4.07+/-1.78 (P > 0.05) and EF = 6.12+/-4.95 (P < 0.05).

IN CONCLUSION

(i) absorption of GA in human skin are pH-, strength- and time-dependent; and (ii) the in vitro method appears to provide an appropriate model to reflect in vivo absorption of GA through human skin.