Keratoacanthoma Centrifugum Marginatum with Atypical Scar

Abstract

Keratoacanthoma centrifugum marginatum (KCM) is a rare variant of keratoacanthoma (KA). It is characterized by a progressive peripheral expansion and central healing leaving atrophic scar. It is sometimes confused with squamous cell carcinoma (SCC) both clinically and histopathologically. We here report a case of KCM over the extensor aspect of the right forearm in a 57-year-old man with an abnormal looking scar.

Keratoacanthoma centrifugum marginatum: A diagnostic and therapeutic challenge

“… 3 Additionally, topical 5-fluorouracil, intralesional injection of methotrexate, interferon alfa, or bleomycin as well as Mohs surgery have successfully been used, but no consensus regimens have been established. 1 , 4 , 9 , 10 No KCM lesions, to our knowledge, have been successfully treated with intralesional 5-flurouracil injection until our case, with complete response and regression of the tumor.…”

“…These lesions are purported to resolve spontaneously if left untreated. 1 , 2 , 3 , 4 KAs typically occur on sun-exposed skin in men past their fifth decade of life. 1 , 2 They usually present as firm, rounded, flesh-colored to red papules with a keratin-filled central crater.…”

“… 1 , 3 These lesions are usually solitary but can be multiple. 4 Three stages characterize the growth course: initial rapid growth, maturation, and spontaneous involution, with each lasting 2 to 6 weeks. 2 , 4 Of the solitary forms, rare variants have been described to include subungual type, intraoral and mucous membrane type, giant KA, and marginated or centrifugum type (also called KCM).…”