Abstract
BACKGROUND: To systematically review the literature on clinicopathological features of keratoacanthomas (KA) in the oral and perioral region. MATERIAL AND METHODS: The review protocol as registered under the number CRD42022323274. Electronic searches were conducted in four databases with a specific search strategy using MeSH and free terms. RESULTS: 60 studies reporting 73 cases of KA were included in this systematic review. KA affects more men with a mean age of 49.09 years old. Sun-exposed area of the lower lip was the most common anatomical location of the perioral lesions (38.35%) and the oral mucosa (9.58%) of the intra-oral ones. The most frequent clinical presentation of the perioral lesions was of an ulcerated nodule (36.23) and intra-orally of an papule (11.59) or nodule (11.59). Incisional biopsies were the commonest procedure for the diagnosis. The histological findings commonly presented a hyperplastic epithelial tissue forming a crater-like structure filled with keratin. Slightly atypia, keratin pearls and an inflammatory infiltrate in connective tissue could also be seen. Surgical excision was the treatment of choice in the majority of cases (45.71%). A low recurrence rate (6.89%) was seen in a mean follow-up time of 20.54 months. CONCLUSIONS: KA affects commonly sun-exposed areas of men in their sixth decade of life. Given the similarity of squamous cell carcinoma, it is important to study KA to help clinicians with the correct diagnosis and treatment.