Epidermal inclusion cysts are caused by an implantation of the epidermal elements. Primary or
congenital epidermoid cysts are related to implantation of ectoderm at time of closure of the neural
groove, or of other epithelial lines. Secondary or acquired epidermoid cysts are usually caused by
post traumatic or iatrogenic inclusion of surface epithelium. We are reporting a case of secondary
epidermoid inclusion cyst on left nasolabial fold after fat injection, which is extremely rare.
A 57-year-old female patient presents with gradually progressive protruding palpable mass on left
nasolabial fold. The patient had history of fat injection 1 year before, and mass was found under the
previous fat injection site. There was no other history of trauma.
The mass was excised and histological examination confirmed the diagnosis of an epidermoid
cyst.
Secondary epidermoid cysts are rare and occur mainly in the fingers, palms, and soles. The cause
of secondary epidermoid cysts has been reported following trauma, radiotherapy, and after surgical
procedures such as needle biopsy. During fat injection, needle injection may cause disruption of the
epithelium and leading to the occurrence of this cyst. So. we suggest a careful procedure during fat
injection.