Intralesional therapy for the treatment of keratoacanthoma

Keratoacanthoma (KA) is a common epidermal tumor that originates from the hair follicle of the skin. It is generally considered as a benign neoplasm, but in rare cases, it can also transform into squamous cell carcinoma. Although surgical excision with a safety margin is considered to be the gold standard treatment for most subtypes of KA, several other treatment options are also available. Intralesional therapy is one of these options, which could be cosmetically and functionally a better alternative to surgical removal, while it provides similar outcomes. It is more effective than topical treatments, yet fewer side effects may be seen than in systemic treatments. Based on the literature, the most commonly used intralesional agent is methotrexate, followed by 5-fluorouracil and interferon alpha. Regardless of the advantages, which make intralesional therapy a desirable treatment alternative, guidelines for the intralesional treatment of KA are not yet established. A histopathological confirmation before the start of treatment is still recommended to prevent any possible misdiagnosis of KA for SCC. In our present study, we set out to review the current state of the art of the intralesional treatment of KA.