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observed. In addition, acanthosis at the edge of the lesions, as well as a band-like lymphocytic infiltrate in the dermis, have been described. Ultrastructural evidences of a decreased number of Odland bodies, that are involved in the normal process of desquamation, have been reported. Several differential diagnoses should be considered, including acrokeratosis verruciformis of Hopf (AVH), disseminated superficial actinic porokeratosis, hyperkeratosis follicularis et follicularis in cutem penetrans (Kyrle’s disease), stucco keratosis, and lichen planus. In our case, AVH was ruled out because the skin features started after the fifth decade of life and the palms were completely spared; in addition, the typical acantopapillomatosis was not detected pathologically. Since the characteristic cornoid lamellae were not observed, disseminated superficial actinic porokeratosis was also excluded. Kyrle’s disease was ruled out because of the absence of focal epidermal perforation and epithelial plug filled with parakeratotic horn material. A stucco keratosis was clinically ruled out since a slight bleeding was not observed after curettage of the hyperkeratotic components of the lesion. Finally, lichen planus was also excluded, because of the absence of K€ oebner phenomenon, hypergranulosis, and interface dermatitis. The therapy is challenging, and several local therapies have been proposed. Topical 5-FU and vitamin D analogs have been reported as successful therapies. Furthermore, topical steroids can be useful only in treating early lesions. Systemic retinoids can improve the clinical picture, while topical retinoids have been reported as not successful. Ablative treatments, such as CO2 laser, dermabrasion, and cryotherapy, seem to be the most effective because they remove the defective keratinocytes. However, because of the multiple number of lesions, these treatments are often unpractical.