Peripheral Neurocytoma Arising from an Ovarian Mature Cystic Teratoma in a Pediatric Patient: Case Report and Literature Review of Published Cases

A neurocytoma is a neuronally-differentiated low-grade tumor most commonly found in young or middle-aged adults. Peripheral neurocytoma arising within mature cystic ovarian teratoma is an extremely rare clinical entity with only few published reports to date. We present a case of a neurocytoma arising within a mature cystic ovarian teratoma in a 16-year- old female. Microscopic examination identified a mature cystic teratoma in addition to a 0.5cm diameter neuroepithelial tumor with neuronal differentiation. The Ki-67 proliferative index was <1%. Immunohistochemistry was positive for synaptophysin and neurofilament and negative for OLIG2 and glial fibrillary acidic protein. Based on these findings, the mass was classified as neurocytoma arising within a mature cystic teratoma.