Nevus sebaceous accompanying secondary neoplasms and unique histopathologic findings.

Nevus sebaceous (NS) is a type of classical nevus or congenital malformation that is often present at birth and commonly involves the scalp or face. The lesion usually presents as a linear, yellow, hairless, and verrucous plaque. It has been well-established that several benign and malignant tumors can develop from the NS; however, there have been no reports about ectopic fat cells in the dermis, and cornoid lamella arising from the NS. We report a case of NS on the scalp with accompanying unusual histopathologic findings.