CSF/brain smear cytology - Rcpa.tv

-well-defined papillary masses with central vascular cores-generally more cellular than normal, several layers of cells surrounding papillarystructures-blood vessels lack the characteristic serpiginous outline seen in normal plexus tissue-central blood vessels less prominent as compared with those in normal smears-nuclei are small, round and uniform-no fibrillary matrix-calcospherites and haemosiderin commonly presentChoroid plexus carcinoma:-presence of many mitoses is a clue (mitoses not seen in papillomas)-less organised papillary architecture-more cellular pleomorphism-proliferation of blood vessels-necrosisDiagnosis of choroid plexus carcinoma should be made withextreme caution in adults. Metastatic adenocarcinoma should beconsidered first: look for acini, goblet cells, mucin production.Neuronal and mixed neuronal-glial tumours:Ganglioglioma / gangliocytoma:-cells have a tendency to form large clusters around blood vessels-large neurons with binucleate or multinucleate forms-may contain a mixture of ganglion cells, astrocytes and perivascular lymphocytes-the pleomorphic glial component may be more conspicuous and mistaken for a highgrade astrocytomaCentral neurocytoma:-sheets of dyscohesive cells with round nuclei, granular chromatin and scantcytoplasm-background of fine fibrillary material-may have multi-branching vessels-calcospherites often seen-diagnosis is made when the intraventricular location of the lesion is known (cytologyis almost identical to that seen in oligodendroglioma)Dysembryoplastic neuroepithelial tumour (DNET):-increased numbers of oligodendroglial-like cells with round nuclei, surrounded bymucoid matrix and prominent blood vessels-floating neurons of normal morphology may be present-reactive astrocytes in the backgroundDysplastic gangliocytoma of cerebellum:-diffuse enlargement of the molecular and internal granular layers of the cerebellumby dysplastic ganglion cells-these ganglion cells have enlarged vesicular nuclei with prominent nucleoli-there are scattered granule cells which are mildly enlarged-Purkinje cells are absent or reduced in number