Miettinen M M, el-Rifai W, Sarlomo-Rikala M, Andersson L C, Knuutila S
Department of Soft Tissue Pathology, Armed Forces Institute of Pathology, Washington, D.C. 20306-6000, USA.
Mod Pathol. 1997 Dec;10(12):1194-200.
Solitary fibrous tumor (SFT) presenting in the pleura and other soft tissue sites and hemangiopericytoma (HPC) presenting at various soft tissue sites are mesenchymal tumors that share many histologic and immunohistochemical features. This raises the questions of whether these tumors are related and whether they belong within the spectrum of a single biologic entity. The behavior of both SFTs and HPCs is difficult to predict histologically. The genetic background of both SFTs and HPCs is poorly known, but it could be helpful in the evaluation of malignancy and could give clues to their possible relationship. In this study, we analyzed 15 SFTs and 11 HPCs by comparative genomic hybridization (CGH), a powerful molecular cytogenetic tool that can be applied to DNA extracted from formaldehyde-fixed and paraffin-embedded tissue. All of these tumors were immunohistochemically similar and showed reactivity for CD34-antigen but not for keratins, desmin, or muscle actins. Only 1 SFT smaller than 10 cm showed DNA copy number changes (a single loss in chromosome 13), but 7 of 8 SFTs larger than 10 cm (including all 4 tumors with more than 4 mitoses per 10 high power fields) showed changes, mostly chromosomal gains in 5q 7, 8, 12, and 18. Four cases showed losses, two of them in chromosome 13 and two others in 20q. These findings suggest that CGH might be useful in the evaluation of malignant transformation in SFT. The most common change, gain of the entire chromosome 8, seen in two cases as the only change, suggests trisomy 8 and parallels a similar finding previously described in other fibrous tumors, such as subsets of desmoid fibromatosis and infantile fibrosarcoma. In contrast, HPCs, including large and mitotically active tumors, showed no DNA copy number changes on CGH. This suggests that HPC is genetically different from SFT.
发生于胸膜和其他软组织部位的孤立性纤维性肿瘤（SFT）以及发生于各种软组织部位的血管外皮细胞瘤（HPC）是具有许多组织学和免疫组化特征的间叶性肿瘤。这就引发了这些肿瘤是否相关以及它们是否属于单一生物学实体范畴的问题。SFT和HPC的组织学行为都难以预测。SFT和HPC的基因背景了解甚少，但这可能有助于评估恶性程度，并可为它们可能的关系提供线索。在本研究中，我们通过比较基因组杂交（CGH）分析了15例SFT和11例HPC，CGH是一种强大的分子细胞遗传学工具，可应用于从甲醛固定、石蜡包埋组织中提取的DNA。所有这些肿瘤在免疫组化上相似，对CD34抗原呈阳性反应，但对角蛋白、结蛋白或肌动蛋白呈阴性反应。只有1例小于10 cm的SFT显示DNA拷贝数改变（13号染色体单一缺失），但8例大于10 cm的SFT中有7例（包括所有每10个高倍视野有超过4个有丝分裂的4个肿瘤）显示改变，主要是5q、7、8、12和18号染色体的获得。4例显示缺失，其中2例在13号染色体，另2例在20q。这些发现表明CGH可能有助于评估SFT的恶性转化。最常见的改变，即整个8号染色体的获得，在2例中作为唯一改变出现，提示8号染色体三体，并与先前在其他纤维性肿瘤（如硬纤维瘤病和婴儿纤维肉瘤的亚型）中描述的类似发现相似。相比之下，HPC，包括大的且有丝分裂活跃的肿瘤，在CGH上未显示DNA拷贝数改变。这表明HPC在基因上与SFT不同。
