Brat D J, Hirose Y, Cohen K J, Feuerstein B G, Burger P C
Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA.
Brain Pathol. 2000 Jul;10(3):342-52. doi: 10.1111/j.1750-3639.2000.tb00266.x.
Astroblastomas are uncommon brain tumors whose classification and histogenesis have been debated. Precise criteria for diagnosis have been described only recently, but have not found wide acceptance. We report the clinical, radiographic, and histopathologic features of 20 astroblastomas, and the chromosomal alterations in seven cases as detected by comparative genomic hybridization (CGH). The tumors occurred both in children and young adults (average age, 14 years), most often as well circumscribed, peripheral, cerebral hemispheric masses. Radiographically, the lesions were contrast-enhancing and solid, often with a cystic component. All were characterized histologically by astroblastic pseudorosettes, and most displayed prominent perivascular hyalinization, regional hyaline changes, and pushing borders in regard to adjacent brain. Tumor cells were strongly immunoreactive for S-100 protein, GFAP, and vimentin. Staining for EMA was focal. Ten of 20 astroblastomas were classified as "well differentiated" and 10 were classified as "malignant," largely on the basis of hypercellular zones with increased mitotic indices, vascular proliferation, and necrosis with pseudopalisading. All 10 well differentiated lesions and 8 of 10 malignant lesions were completely resected. None of the well differentiated astroblastomas recurred within the limited follow-up period. Three malignant astroblastomas recurred, including two incompletely resected tumors, and one that had been totally resected. One patient died of disease following recurrence. The most frequent chromosomal alterations detected by CGH were gains of chromosome arm 20q (4/7 tumors) and chromosome 19 (3/7). The combination of these gains occurred in three, including two well differentiated and one malignant astroblastoma. Other alterations noted in two tumors each were losses on 9q, 10, and X. These chromosomal alterations are not typical of ependymoma or infiltrating astrocytic neoplasms, and suggest that astroblastomas may have a characteristic cytogenetic profile in addition to their distinctive clinical, radiographic, and histopathologic features.
成星形细胞瘤是一种罕见的脑肿瘤，其分类和组织发生一直存在争议。直到最近才描述了精确的诊断标准，但尚未得到广泛认可。我们报告了20例成星形细胞瘤的临床、影像学和组织病理学特征，以及通过比较基因组杂交（CGH）检测的7例病例的染色体改变。这些肿瘤发生于儿童和年轻人（平均年龄14岁），大多为边界清楚的外周性大脑半球肿块。影像学上，病变呈强化实性，常伴有囊性成分。所有病例在组织学上均以成星形细胞假菊形团为特征，大多数表现为明显的血管周围玻璃样变、局部玻璃样改变以及与相邻脑组织的推移边界。肿瘤细胞对S-100蛋白、GFAP和波形蛋白呈强免疫反应性。EMA染色呈局灶性。20例成星形细胞瘤中，10例被分类为“高分化”型，10例被分类为“恶性”型，主要依据是有丝分裂指数增加的高细胞区、血管增生以及伴有假栅栏状的坏死。所有10例高分化病变和10例恶性病变中的8例均被完整切除。在有限的随访期内，所有高分化成星形细胞瘤均未复发。3例恶性成星形细胞瘤复发，包括2例未完整切除的肿瘤和1例已完全切除的肿瘤。1例患者复发后死于疾病。通过CGH检测到的最常见染色体改变是20q染色体臂增加（4/7肿瘤）和19号染色体增加（3/7）。这两种增加同时出现的情况有3例，包括2例高分化和成1例恶性成星形细胞瘤。另外在2例肿瘤中各观察到的改变是9q、10号染色体和X染色体缺失。这些染色体改变并非室管膜瘤或浸润性星形细胞肿瘤的典型特征，提示成星形细胞瘤除了具有独特的临床、影像学和组织病理学特征外，可能还具有特征性的细胞遗传学图谱。
