By Gary M. White, MD

Keratoacanthoma Centrifugum Marginatum

Keratoacanthoma Centrifugum Marginatum (KCM) is a rare, large variant of the classic keratoacanthoma (KA).


A progressively enlarging verrucous lesion with central clearing or atrophy is characteristic. The periphery of the lesion shows typical features of KA while the center may show atrophy and dermal scarring. Diameters from 5 cm up to 30 cm have been reported. Some lesions have progressed over many years. This lesion should be contrasted with the giant KA which may be large (e.g., over 3 cm) but does not show central regression.


Spontaneous resolution has been reported to occur but this cannot be relied upon. Some sort of therapy is indicated. Curettage or simple excision may be done for smaller lesions. Otherwise Mohs surgery, followed by grafting, may be needed. Radiation therapy has been used. Intralesional bleomycin is a reasonable alternative (1 mg/ml diluted with lidocaine. 0.2 mg injected into each of 4 sites weekly for 3 weeks JAAD 1998;37;1010). IL 5-fluorouracil has also been used successfully (2 courses of intralesional 5% 5-fluorouracil injectable solution consisting of 0.6 mL divided into 3 aliquots within the tumor mass--separated by 3 weeks JAAD Case Report 2016;2;206–208). Other treatments have included topical imiquimod, etretinate, methotrexate, photodynamic therapy, and systemic erlotinib (Tarceva). For multiple KCM, oral retinoids are usually recommended, e.g., acitretin. One patient with over 30 lesions did well on acitretin (0.5–0.7 mg/kg/day) [Dermatologica Sinica 32 (2014) 25-28].


Keratoacanthoma centrifugum marginatum—A rare variant of keratoacanthoma: Case report and literature review Dermatologica Sinica 32 (2014) 25-28


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