Keratoacanthoma on facial skin : case report

Kang, Hee ln; Lee, Won Hak; Oh, Hae Soo; Kim, Dong Suk; Kim, Sang Joong

Abstract

Keratoacanthoma is a benign, self-limited epithelial lesion that closely resembles Squamous cell carcinoma(SCC). Keratoacanthoma occur primarily exposed skin in male patients over 45 years of ages. although etiology is unknown, sunlight, genetic, and human papillomavirus factor have been considered. in clinical feature, rapid enlargement occurs over 4.8 weeks, resulting ultimately in a hemispheric, firm, elevated, asymptomatic nodule that contains a central plug of keratin. When fully developed, the keratoacanthoma contains a core of keratin surrounded by a concentric collar of raised skin. Over the next 4.8 weeks, static lesion persists. Then undergoes spontaneous regression over the next 6.8weeks period by expulsion of the keratin core with resorption of the mass. In histologic feature, Keratoacanthoma consists of hyperplastic squamous epithelium growing into the underlying connective tissue. The surface is covered by a thickened layer of parakeratin with central plugging. Epithelium cell shows dysplastic features and the margins the normal adjacent epithelium is elevated. The differential diagnosis includes SCC. Keratoacanthoma present as a exophytic lesion with horny keratin occupying a depression on the top of the lesion, persists static period and undergoes rapid growth compared with SCC. Keratoacanthoma is usually treated by surgical excision or curettage of the base, spontaneous regression does not occur in every case. A 60 years old male who present facial lesion visit our hospital and surgical excision was done. Biopsy result was keratoacanthoma. We report case with review of literatures.