Cerebellopontine angle invasive papillary cystadenoma of endolymphatic sac origin with temporal bone involvement

The authors report the MR, CT, and pathologic findings in a case of invasive papillary cystadenoma originating in the endolymphatic sac and involving the temporal bone. This case illustrates characteristic imaging features of this lesion. The authors emphasize awareness of this entity with its aggressive temporal bone involvement as an aid to pathologic differential diagnosis.