The lesion was a cutaneous horn, or cornu cutaneum, a cohesive, keratotic, protuberant mass arising from the strateum corneum, or “horny layer.” Cutaneous horns are composed of compacted keratin, ...

Regular skin exams can identify suspicious lesions, but an accurate diagnosis requires a biopsy. During the biopsy, a doctor will inject a local anesthetic in the area of the lesion and then remove a ...