This Publication Is Searchable The Merck Manual of Diagnosis and Therapy Section 10. Dermatologic Disorders Chapter 125. A round, firm, usually flesh-colored nodule with sharply sloping borders and a characteristic central crater containing keratinous material.
Common sites are sun-exposed areas, the face, the forearm, and the dorsum of the hand.
Spontaneous involution usually starts within a few months. This lesion is sometimes difficult to differentiate clinically and histologically from squamous cell carcinoma. All rights reserved.