Department of Pathology, Duke University Medical Center, Durham, North Carolina.
Department of Neurosurgery, Yale University, New Haven, Connecticut.
J Neuropathol Exp Neurol. 2019 Sep 1;78(9):780-787. doi: 10.1093/jnen/nlz060.
Infratentorial glioneuronal neoplasms are overall quite rare and are more commonly low-grade with surgical excision usually being curative. Multiple distinct histologic entities have been described including rosette-forming glioneuronal tumor, papillary glioneuronal tumor, neurocytoma, dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos disease), cerebellar liponeurocytoma, and ganglioglioma. While each of these entities has distinct findings, in some instances a tumor may demonstrate overlapping histologic features with mixed components. Herein, we report 2 unusual adult cases of a fourth ventricular glioneuronal tumor with features of ganglioglioma and neurocytoma, with one coming from a surgical resection and one found incidentally at autopsy. To the best of our knowledge, this specific histologic combination has not previously been described. As such, the clinical significance is unknown although in both cases the neoplasms were circumscribed and appeared to be low grade. The presence of the gangliogliomatous component was of particular interest since these are extremely rare occurrences in the fourth ventricle and we provide a comprehensive review of infratentorial gangliogliomas.
小脑幕下神经胶质神经元肿瘤总体上较为罕见，多为低级别肿瘤，手术切除通常可达到治愈效果。已经描述了多种不同的组织学实体，包括菊形团形成性神经胶质神经元肿瘤、乳头状神经胶质神经元肿瘤、神经细胞瘤、小脑发育不良性神经节细胞瘤（Lhermitte-Duclos 病）、小脑脂肪神经细胞瘤和神经节胶质瘤。虽然这些实体具有不同的特征，但在某些情况下，肿瘤可能具有混合成分的重叠组织学特征。在此，我们报告了 2 例罕见的成人第四脑室神经胶质神经元肿瘤病例，其特征为神经节胶质瘤和神经细胞瘤，其中 1 例来自手术切除，1 例偶然尸检发现。据我们所知，这种特定的组织学组合以前尚未描述过。因此，尽管这两种情况下肿瘤都是局限性的且似乎为低级别，但肿瘤的临床意义尚不清楚。神经节胶质瘤成分的存在特别有趣，因为这些在第四脑室中极为罕见，我们提供了对小脑幕下神经节胶质瘤的全面回顾。
