Division of Thoracic Oncology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777, Japan.
Eur J Radiol. 2012 Sep;81(9):2423-9. doi: 10.1016/j.ejrad.2011.09.017. Epub 2011 Nov 4.
The usefulness of 2-[(18)F]-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography (PET) has been investigated in thymic epithelial tumors. However, little is known about PET imaging of (18)F-FDG in primary non-thymic mediastinal neoplasms. The aim of this study is to explore the clinicopathological significance of (18)F-FDG PET in primary mediastinal (non-thymic) neoplasms.
Twenty-one patients with mediastinal neoplasms who underwent (18)F-FDG PET before treatment were included in this study. Tumor sections were stained by immunohistochemistry for glucose transporter 1 (Glut1); glucose transporter 3 (Glut3); hypoxia-inducible factor-1 alpha (HIF-1α); hexokinase I; vascular endothelial growth factor (VEGF); microvessels (CD34); epidermal growth factor receptor (EGFR); Akt/mTOR signaling pathway (p-Akt and p-mTOR); cell cycle control (p53).
Seventeen of 21 patients were imaged on PET system using (18)F-FDG, but 4 patients with a histology of cyst showed nothing abnormal in PET scans. The histology of the resected tumors was as follows: 6 schwannoma, 3 teratoma, 4 cyst, 3 sarcoma, 1 undifferentiated carcinoma, 1 seminoma, 1 mediastinal goiter, 1 ganglioneuroma, and 1 Hodgkin lymphoma. (18)F-FDG uptake was significantly correlated with Glut1, HIF-1α, EGFR, p-Akt and p-S6K. These biomarkers were highly expressed in schwannoma, teratoma and high grade malignancies, whereas all patients with cyst and ganglioneuroma had no positive expression of these biomarkers. High uptake of (18)F-FDG was significant associated with Glut1, VEGF, EGFR, p-Akt, p-S6K and tumor maximal size.
The amount of (18)F-FDG uptake in primary mediastinal non-thymic neoplasms is determined by the presence of glucose metabolism (Glut1), hypoxia (HIF-1α) and upstream components of HIF-1α (EGFR, p-Akt and p-S6K).
2-[(18)F]-氟-2-脱氧-D-葡萄糖（(18)F-FDG）正电子发射断层扫描（PET）在胸腺癌中的应用已得到研究。然而，关于原发性非胸内纵隔肿瘤的(18)F-FDG PET 成像知之甚少。本研究旨在探讨(18)F-FDG PET 在原发性纵隔（非胸内）肿瘤中的临床病理意义。
本研究纳入 21 例接受治疗前(18)F-FDG PET 检查的纵隔肿瘤患者。肿瘤切片用免疫组织化学法染色，检测葡萄糖转运蛋白 1（Glut1）、葡萄糖转运蛋白 3（Glut3）、缺氧诱导因子-1α（HIF-1α）、己糖激酶 I、血管内皮生长因子（VEGF）、微血管（CD34）、表皮生长因子受体（EGFR）、Akt/mTOR 信号通路（p-Akt 和 p-mTOR）、细胞周期调控（p53）。
21 例患者中有 17 例在 PET 系统上用(18)F-FDG 成像，但 4 例组织学为囊肿的患者 PET 扫描未见异常。切除肿瘤的组织学如下：6 例神经鞘瘤、3 例畸胎瘤、4 例囊肿、3 例肉瘤、1 例未分化癌、1 例精原细胞瘤、1 例纵隔甲状腺肿、1 例神经节细胞瘤和 1 例霍奇金淋巴瘤。(18)F-FDG 摄取与 Glut1、HIF-1α、EGFR、p-Akt 和 p-S6K 显著相关。这些生物标志物在神经鞘瘤、畸胎瘤和高级别恶性肿瘤中高度表达，而所有囊肿和神经节细胞瘤患者均无这些标志物的阳性表达。(18)F-FDG 摄取量与 Glut1、VEGF、EGFR、p-Akt、p-S6K 和肿瘤最大直径显著相关。
原发性纵隔非胸内肿瘤(18)F-FDG 摄取量取决于葡萄糖代谢（Glut1）、缺氧（HIF-1α）和 HIF-1α 的上游成分（EGFR、p-Akt 和 p-S6K）的存在。
