Suspicious Papule on Lower Vermillion Border

Abstract

Molluscum contagiosum (MC) is a highly contagious, cutaneous infection caused by a double-stranded DNA poxvirus. Mollusca are characterized by a firm, dome-shaped, flesh-colored, pearly papule with a white, umbilicated center. Generally, lesions occur in clusters and range in size from 1 to 5 millimeters. Although unusual and infrequent, MC occurring in an epidermal inclusion cyst has been reported. This case involves an 83-year-old woman with a flesh-colored, slightly tender papule on the right lower vermillion border, which had been enlarging over several months. Histopathology showed prominent molluscum bodies present in the adjacent epidermis and focally lining the central epidermal cyst. The findings observed in this case support the hypothesized pathophysiological co-inoculation theory for the development of molluscum-infected epidermal inclusion cysts. This is clinically significant given the infectivity of cyst contents and the potential for direct inoculation of the cyst. Given its rarity, treatment protocols for epidermal inclusion cysts containing MC have not been established. However, management requires care to avoid viral transmission.