Seborrheic Keratoses - The Most Common Benign Skin Tumor of Humans. Clinical presentation and an update on pathogenesis and treatment options.

Seborrheic keratoses (SK) are the most common skin tumour of humanity. The incidence of this purely benign epithelial proliferation is increasing with age and exposure to ultraviolet light. It has a remarkable variability in its clinical presentation raising some differential diagnoses. Recently, oncogenic mutations have been detected involved in the development of SK, which, however, do not bear the risk of malignant transformation. SK may also develop with the use of modern targeted drugs for the treatment of malignancies. The classical treatment options for SK are cryotherapy and curettage. Recently, topical treatment with 40% hydrogen peroxide and the nitric-zinc complex has been investigated. Ablative laser therapy is an effective treatment as well.