Papillary ependymomas

In contrast to papillary ependymoma, the choroid plexus papilloma contains a layer of columnar to cuboidal epithelial cells over a basement membrane and fibrovas-cular stroma. The type IV collagen and laminin in this stroma contrast with ependymomas, which have solid parenchyma without collagen or laminin (see Tables... 

The recognition of a papillary meningioma in other than the dural locations characteristic of meningioma is difficult. Papillary meningiomas resemble papillary ependymomas, choroid plexus papillomas, and carcinomas.One should look for a high ratio of vimentin to CK and absence of GFAP to identify the meningioma. 

---