A Clinical and Histopathological Study of 324 Cases of Epidermal Cyst / 대한피부과학회지

ABSTRACT

BACKGROUND: Epidermal cysts are a common occurrence. But there have been few studies to determine the clinical and histopathological characteristics of epidermal cysts. OBJECTIVE: To evaluate the clinicopathological characteristics of 324 cases of epidermal cyst. METHODS: We evaluated the clinical and histopathologic features of 324 cases of epidermal cyst at the Department of Dermatology at Korea University Anam Hospital over 5 years, from January 2001 to December 2005. RESULTS: The ratio of male to female patients was 1.7 1. Age distribution ranged from 7 to 91 years old. The duration of lesions was variable with mean duration of 29.3 months. The most common site of occurrence was the face. Histopathologic changes of cystic walls were atropy, acanthosis, hypergranulosis, vacuolation and parakeratosis. We identified parakeratotic cells, red blood cells, calcifications and bacterial colonies in the cystic contents. We also found verrucous architectures in the cystic walls of 23 cases. Initially, some cases were clinically diagnosed as epidermal cysts, but histopathological findings then discovered only inflammation, granulation, pilomatrichoma or lipoma, rather than an epidermal cyst. We discovered that there was also a close relation between erythema and rupture of the cystic wall. CONCLUSION: Our clinical and histopathologic findings of the epidermal cysts were similar to previous reports. However, we did find verrucous architectures on not only the palmoplantar area, but also many other areas of the body. Quite a few cases which had initially been clinically diagnosed as epidermal cysts, turned out not to be upon histopathologic investigation.