Congenital dermal sinus and cyst in adulthood.

Dermal sinus tracts are formed during the 26th day of gestation from the incomplete closure of cutaneous ectoderm from neural ectoderm.1-5 As remnants of incomplete neural tube closure, they are often associated with dermoid and epidermoid cysts, spinal cord tethering and spinal fluid drainage.1,2,6-8 As such, dermal sinus tracts are diagnosed during early childhood.2,8 These entities most frequently present in the lumbosacral area and less commonly in the thoracic region.2,8-10 We present a patient with a thoracic dermal sinus tract and an associated intradural dermoid cyst presenting in late adulthood.