CENTRAL NEUROCYTOMA - A CLINICOPATHOLOGICAL, IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL-STUDY OF 7 CASES

Characterised by distinctive clinicopathological features, the central neurocytoma (CN) is an uncommon and possibly under-recognised primary cerebral neuronal neoplasm. We present clinical and pathological deta ils of seven patients with CN. Histological examination revealed a gre ater diversity of morphological appearances than is typically describe d in CN. No anaplastic features were identified. Cellular areas resemb ling both oligodendroglioma and ependymoma were present in all cases, but each tumour also contained stroma rich areas with hyalinised or an eurysmal vessels. Synaptophysin was expressed by all tumours and proba bly represents the immunohistochemical marker of choice for identifyin g CN. Distinguishing ultrastructural features included rounded cell bo dies separated by numerous cell processes containing microtubules, ple omorphic neurosecretory granules and occasional synapses. Ki-67 immuno staining revealed a low cell proliferation index in each case. The dis tinction of CN from other pathological mimics can be reliably made usi ng this multiparametric approach to diagnosis. The generally benign be haviour of CN is confirmed, though there was one patient death in the follow-up period of 10-122 months. Aggressive behaviour in this case w as not associated with anaplastic histological features.