Imaging of atypical choroid plexus papillomas.

The authors report a rare case of benign choroid plexus papilloma arising in the cerebellopontine angle (CPA) in a 34-year-old man. Atypical features are described. This is the fourth case of MR evaluation of such tumor in available literature and the second case in the United States. Differential diagnosis is discussed. Choroid plexus papilloma should be considered among calcified, vascular, enhancing masses of CPA even in adulthood. The authors also report an unusual case of choroid plexus carcinoma.