Meningioma with perivascular pseudorosettes: a morphological entity distinct from papillary meningioma?

Although papillary meningioma is a well known variant of meningiomas, many of the previously reported cases do not seem to contain structures that fulfill the classical microscopic descriptions of a papilla. The case of a 79-year-old man with a meningioma of the convexity is described. This meningioma was totally removed but recurred 36 months after surgery. The main cellular components of the tumor, some of them mimicking astrocytic cells, were arranged preferentially around vessels featuring perivascular pseudorosettes. The survey of the literature stresses a possible morphological misinterpretation of some of the mentioned papillary variants. Although both papillary variants and those with perivascular pseudorosettes seem to display a similar, not always malignant, behavior, strictly from the morphological point of view they should be separated.