The natural history of a recurrent central neurocytoma-like tumor.

The central neurocytoma was first recognized as a distinct entity in 1982. The original description was of a low grade, intraventricular neoplasm composed of uniform cells showing neuronal differentiation, and having a very favorable prognosis after surgery. Subsequently rare cases have been described showing malignant histological features but retaining the morphological characteristics that justify inclusion in this category. The behavior of such cases has yet to be determined. We report a case of a longstanding intraventricular tumor showing neuronal differentiation in which repeated recurrences following surgery have revealed evidence of increasing nuclear pleomorphism, mitotic activity and glial differentiation. We suggest that this tumor broadens further the clinical and pathological spectrum of central neurocytoma.