Nagasaka Toru, Gunji Masaharu, Hosokai Noboru, Hayashi Kumiko, Ikeda Hiroshi, Ito Masafumi, Inao Suguru
Department of Neurosurgery, Japanese Red Cross Nagoya First Hospital, Nagoya, 453-8511, Japan.
Brain Tumor Pathol. 2007;24(1):1-5. doi: 10.1007/s10014-006-0209-6. Epub 2007 May 25.
Glioblastoma is the most malignant and frequent of the glial tumors. A minor fraction of glioblastoma may contain areas showing oligodendroglioma-like tumor cell differentiation. Several authors have described such tumors as glioblastoma with oligodendroglial component (GBMO). GBMO may represent the ultimate level of malignancy in the oligodendroglial lineage. The oligodendroglial component and combined loss of chromosomal arm 1p and 19q in glioblastoma indicate increased survival. In our study, we analyzed 1p and 19q status in a series of 12 glioblastoma and 8 oligodendroglial tumors using fluorescence in situ hybridization (FISH) on paraffin-embedded tissues. In each case, hybridization status was classified as deletion, imbalance, polysomy, amplification, or normal pattern. Other genetic alterations such as CDKN2A (p16), RB, and EGFR were also assessed. On histological review, 2 of 12 glioblastoma (16.7%) were classified as GBMO. Chromosome 1p/19q deletion was detected in 3 of 12 glioblastomas (25%). In contrast, all 8 oligodendroglial tumors showed 1p/19q deletion. All GBMO had 19q deletion with imbalance, whereas 1 of 10 ordinary glioblastoma (10%) demonstrated 19q deletion with imbalance. All but 1 ordinary glioblastoma (90%) showed CDKN2A (p16) deletion, but no GBMO displayed this alteration. Our results indicate that GBMO may be a distinct subtype of glioblastoma harboring a characteristic molecular profile. FISH on paraffin-embedded specimens is a useful method for subclassification of glioblastoma.
胶质母细胞瘤是最恶性且最常见的神经胶质瘤。一小部分胶质母细胞瘤可能包含显示少突胶质细胞瘤样肿瘤细胞分化的区域。几位作者将此类肿瘤描述为具有少突胶质细胞成分的胶质母细胞瘤（GBMO）。GBMO可能代表少突胶质细胞谱系中的最终恶性程度。胶质母细胞瘤中的少突胶质细胞成分以及染色体臂1p和19q的联合缺失表明生存期延长。在我们的研究中，我们使用石蜡包埋组织的荧光原位杂交（FISH）分析了一系列12例胶质母细胞瘤和8例少突胶质细胞瘤的1p和19q状态。在每种情况下，杂交状态被分类为缺失、不平衡、多体性、扩增或正常模式。还评估了其他基因改变，如CDKN2A（p16）、RB和EGFR。经组织学检查，12例胶质母细胞瘤中有2例（16.7%）被分类为GBMO。12例胶质母细胞瘤中有3例（25%）检测到染色体1p/19q缺失。相比之下，所有8例少突胶质细胞瘤均显示1p/19q缺失。所有GBMO均有19q缺失伴不平衡，而10例普通胶质母细胞瘤中有1例（10%）显示19q缺失伴不平衡。除1例普通胶质母细胞瘤外，所有其他普通胶质母细胞瘤（90%）均显示CDKN2A（p16）缺失，但没有GBMO显示这种改变。我们的结果表明，GBMO可能是具有特征性分子谱的胶质母细胞瘤的一种独特亚型。石蜡包埋标本的FISH是胶质母细胞瘤亚分类的一种有用方法。
