A. Squamous Cell Carcinoma
C. Verrucous Carcinoma
D. Cutaneous Horn
- Keratoacanthoma is a relatively common low-grade tumor that originates in the pilosebaceous glands and closely resembles squamous cell carcinoma .
- Keratoacanthoma is characterized by rapid growth over a few weeks to months, followed by spontaneous resolution over 4-6 months in most cases. Keratoacanthoma may progress rarely to invasive or metastatic carcinoma.
- Trauma, ultraviolet light, chemical carcinogens, human papillomavirus, genetic factors, and immunocompromised status have been implicated as etiologic or triggering factors.
- The prognosis for keratoacanthoma is excellent following excisional surgery. Recurrent tumors may require more aggressive therapy.
- Lesions typically are solitary and begin as firm, roundish, skin-colored or reddish papules that rapidly progress to dome-shaped nodules with a smooth shiny surface and a central crateriform ulceration or keratin plug that may project like a horn. Most keratoacanthomas occur on sun-exposed areas. The face, neck, and dorsum of the upper extremities are common sites.
- Keratoacanthomas (KAs) are composed of singularly well-differentiated squamous epithelium that show only a mild degree of pleomorphism and likely form masses of keratin that constitute the central core of keratoacanthoma.
- The primary therapy for keratoacanthoma is surgical excision of the tumor.