Dorsal giant skin horn: a clinical-histological study

Abstract

Abstract: 

Introduction: The term cutaneous horn refers to a cone-shaped structure consisting of keratin, which, unlike animal horns, lacks a bony core.

They appear more frequently on the face, ears, and the back of the hands, in elderly people with keratin-producing injuries. These can be benign, premalignant or malignant. We present this case because of its infrequent location, its extreme length, and its long evolution. Furthermore, although the clinical features are especially notorious, what is significant in these injuries is that they may be a malignancy macroscopic manifestation.

Case Presentation: An 88-year-old woman arrived with a long-standing injury on her back. Surgery was performed and the cutaneous horn was removed. Macroscopy: We received a cutaneous horn of keratinous appearance measuring 30 cm and a maximum diameter of 5 cm, with a 1-cm-thick skin lozenge measuring 4 cm in diameter. Sections of the skin injury were cut and processed with the common hematoxylin/eosin staining technique.

Histologically, the baseline skin injury was a verrucous carcinoma shaped by solid nests and cords, with the formation of keratin pearls and marked hyperkeratosis. Nuclear grade and mitotic count were low. The surrounding stroma was desmoplastic with mild, diffuse inflammatory infiltrate, and no lymphatic or hematic vascular infiltration was observed. Neoplasm invaded deep into the lower third of the reticular dermis. Surgical margins were free.

Conclusion: This type of injury, no matter how harmless it may seem, must be removed with a wide margin of healthy tissue, since in many instances the underlying process that causes the hyperkeratosis is of neoplastic nature, as in this case. It should only be referred to as a cutaneous horn when the underlying injury is epidermal hyperplasia. On the other hand, we have not found bibliography with a cutaneous horn of these dimensions, resembling an animal horn.