Synchronous occurrence of multiple primary central nervous system (CNS)
tumors of different histological types is uncommon in patients without radiation history or genetic syndrome association. We herein report a sporadic case of
posterior fossa tumor with synchronous
choroid plexus papilloma (
CPP) and
ependymoma (EP) components. A 7-year-old girl with no significant past or familial medical history presented with 2 years of
migraine type
headaches. Brain magnetic resonance imaging showed a cystic mass with a mural enhancing nodule centered within the cerebellar vermis. The patient underwent gross total resection of the
tumor. Histologic examination showed a
tumor with two distinct components. The predominant component demonstrated classic morphological and immunohistochemical characteristics of
choroid plexus papilloma CPP, WHO grade I. However, there were a few discrete foci, where
tumor cells showed architectural, cytological, and immunohistochemical features characteristic of an
ependymoma, WHO grade II. In addition, there was exuberant piloid
gliosis secondary to infiltration of the
CPP component into the adjacent brain parenchyma. Followup brain imaging at 14 months after surgery showed no evidence of residual or recurrent
tumor. To the best of our knowledge, this is the first reported case of synchronous
CPP and EP in the posterior fossa.