Ceppa Eugene P, Bouffet Eric, Griebel Robert, Robinson Chris, Tihan Tarik
Department of Pathology, University of California, Neuropathology Unit, 513 Parnassus Avenue, HSW 408 Box 0511, San Francisco, CA 94143-0511, USA.
J Neurooncol. 2007 Jan;81(2):191-6. doi: 10.1007/s11060-006-9216-z. Epub 2006 Jul 19.
Pilomyxoid astrocytoma (PMA) is a rare glioma that shares histopathological similarities with pilocytic astrocytoma (PA). Yet, typical examples of both can be distinguished on clinical and histological grounds. The reported aggressive behavior of PMA provides a rationale for distinguishing this entity from typical PA. We report a 6(1/2) -year-old girl who had suffered poor weight gain, irritability and progressively worsening abnormal eye movements since approximately 2 months of age. Radiographic studies at 6 months of age (age at initial presentation) revealed a large hypothalamic lesion occupying proximal portions of the optic nerves, chiasm and right posterior optic tract. The first biopsy obtained after two chemotherapy regimens was consistent with a diagnosis of PMA. The patient suffered multiple recurrences, and underwent three subsequent surgical procedures. The last two surgical specimens revealed a tumor with histopathological features of PA. She is alive with residual disease 6 years after initial presentation. While earlier studies focused on the similarities between PA and PMA, considering the latter as the "infantile" form of the former, subsequent work outlined their histological and clinical differences. Some even suggested a different cell type, such as the tanycytic cell as the origin for PMA. This report provides evidence in favor of the earlier argument that there is a close relationship between PA and PMA, and presents a rare "maturation" phenomenon, at least from a morphological perspective. More systematic review of such cases will provide a better answer for the origin of PMA, and its relation to PA.
毛黏液样星形细胞瘤（PMA）是一种罕见的胶质瘤，在组织病理学上与毛细胞型星形细胞瘤（PA）相似。然而，两者的典型病例在临床和组织学上是可以区分的。PMA具有侵袭性的报道为将该实体与典型PA区分开来提供了理论依据。我们报告了一名6岁半的女孩，自大约2个月大以来体重增长不佳、易怒且异常眼动逐渐加重。6个月大时（首次就诊年龄）的影像学检查显示下丘脑有一个大的病变，占据了视神经近端、视交叉和右侧视束。在两种化疗方案后进行的首次活检结果符合PMA的诊断。该患者多次复发，并接受了三次后续手术。最后两次手术标本显示肿瘤具有PA的组织病理学特征。初次就诊6年后，她仍存活但有残留病灶。虽然早期研究关注PA和PMA之间的相似性，将后者视为前者的“婴儿型”，但随后的研究概述了它们在组织学和临床方面的差异。一些人甚至提出了不同的细胞类型，比如伸长细胞作为PMA的起源。本报告为早期关于PA和PMA之间存在密切关系的观点提供了证据，并呈现了一种罕见的“成熟”现象，至少从形态学角度来看是这样。对这类病例进行更系统的回顾将为PMA的起源及其与PA的关系提供更好的答案。
