HPV-related Epidermal Cyst
Elsa F. Velazquez, MD
David Cassarino, MD, PhD
Key Facts
Etiology/Pathogenesis
HPV-related cysts
Verrucous cysts have been reported to be associated with HPV-20 and -34
Epidermoid cyst of the palm and sole is associated with HPV-60 and -57 (affects Japanese)
Microscopic Pathology
Verrucous epidermal cyst
Papillary and acanthotic squamous epithelium with hypergranulosis and hyperkeratosis (focal parakeratosis)
Keratohyalin granules
Koilocytic change
Epidermoid cyst of the palm and sole
Epidermis-like lining
Eosinophilic intracytoplasmic inclusions in wall
Vacuolated cells in keratin contents
 Verrucous epidermal cyst shows an acanthotic and papillated epithelial structure in the dermis. Note the separation from the epidermis  . |
 High magnification shows the acanthotic epithelium of an HPV-related verrucous epidermal cyst showing prominent keratohyaline granules  and koilocytosis  . |
TERMINOLOGY
Synonyms
Verrucous cyst, epidermoid cyst of the palm and sole
Definitions
Epidermoid cysts associated with human papillomavirus (HPV) infection
ETIOLOGY/PATHOGENESIS
Infectious Agents
Human papillomaviruses (HPV)
Verrucous cysts have been reported to be associated with HPV-20 and -34 (epidermodysplasia verruciformis strains)
Epidermoid cyst of the palm and sole mainly associated with HPV-60 and -57
Traumatic implantation of HPV-infected epidermis (or perhaps eccrine ducts) into dermis
CLINICAL ISSUES
