Squash cytomorphology of central neurocytoma: a study of five cases.

Intraoperative consultation is an important component in the surgical management of brain tumors. This study was undertaken to describe the cytomorphological features of central neurocytoma (CN) in squash smears. Squash smear of five CNs were reviewed. One to two millimeters of the biopsy material was crushed between two glass slides to make a thin film that was fixed in 95% alcohol and stained with haematoxylin and eosin (H&E). Cytological diagnoses were correlated with clinical and radiological data and finally with histopathological findings in the tumor. We had 5 cases (4 males, 1 female; age, 19-61 years; mean, 32 years). All tumors were located in the lateral ventricle. The smears were highly cellular displaying monomoprhic round tumor cells, round to oval nuclei with evenly distributed finely granular chromatin and ill-defined cytoplasmic borders within fibrillar matrix. Focal rosette formation is also noted. A capillary network was identified in between tumor cells in all the cases. One case had calcification with numerous psamomma bodies identified in the squash smear. The differential diagnosis is discussed. On squash smears, CN can be diagnosed when cytomorphological features are correlated with clinical and radiological finding.