Gagel Bernd, Reinartz Patrick, Dimartino Ercole, Zimny Michael, Pinkawa Michael, Maneschi Payam, Stanzel Sven, Hamacher Kurt, Coenen Heinz H, Westhofen Michael, Büll Ulrich, Eble Michael J
Department of Radiotherapy, University of Aachen, Aachen, Germany.
Strahlenther Onkol. 2004 Oct;180(10):616-22. doi: 10.1007/s00066-004-1229-y.
The aim of the present study was to validate ([(18)F] fluoromisonidazole (FMISO) and [(18)F]-2-fluoro-2'-deoxyglucose (FDG) positron emission tomography (PET) for determination of radiotherapeutically relevant hypoxia by the gold standard for measuring tissue oxygenation in human tumors, the computerized polarographic needle electrode system (pO(2) histography).
Up to now, a total of 16 patients with a metastatic neck lymph node from a primary squamous carcinoma of the head and neck underwent pO(2) and PET measurements. Tumor tissue pO(2) was measured with polarographic needle electrodes using a pO(2) histograph (Eppendorf). Under CT control, the needle electrode was placed in the tumor without general or local anesthesia. To assess the biological and clinical relevance of oxygenation measurement, the relative frequency of pO(2) readings, with values < or = 2.5, < or = 5.0, and < or = 10.0 mmHg, as well as mean and median pO(2) were recorded. All PET studies were carried out using an ECAT EXACT 922/47 scanner with an axial field of view of 16.2 cm. FMISO PET consisted of one static scan of the relevant region, performed 120 min after intravenous administration. The acquisition and reconstruction parameters were as follows: 15-min emission scanning and 4-min transmission scanning with (68)Ge rod sources. FDG PET of the lymph node metastasis was performed 68 +/- 11 min after intravenous administration, applying the whole-body tool with 8-min emission scanning and 4-min transmission scanning per bed position.
In order to detect possible relations between the different relevant polarographically measured parameters of tumor hypoxia and FMISO PET data-based oxygenation values, the Pearson correlation coefficient was calculated. Average (r > 0.5) to high correlation (r > 0.7) was found between tumor-to-muscle ratio of FMISO after 2 h and parameters of hypoxic fraction (pO(2) readings with values <or = 2.5, < or = 5.0, and < or = 10.0 mmHg as well as mean and median). No correlations could be shown between FDG PET parameters and polarographically determined tumor oxygenation status.
Summarizing the FMISO uptake represents a global value for macroscopic tumor parts. As a noninvasive measurement this method seems highly feasible to evaluate the state of oxygenation in subjacent tumors.
本研究的目的是通过测量人体肿瘤组织氧合的金标准——计算机化极谱针电极系统（pO₂组织成像），验证[¹⁸F]氟米索硝唑（FMISO）和[¹⁸F]-2-氟-2'-脱氧葡萄糖（FDG）正电子发射断层扫描（PET）用于确定放射治疗相关缺氧情况的有效性。
截至目前，共有16例头颈部原发性鳞状细胞癌颈部转移淋巴结患者接受了pO₂和PET测量。使用pO₂组织成像仪（Eppendorf）通过极谱针电极测量肿瘤组织的pO₂。在CT引导下，无需全身或局部麻醉，将针电极置于肿瘤内。为评估氧合测量的生物学和临床相关性，记录pO₂读数相对频率（值≤2.5、≤5.0和≤10.0 mmHg）以及平均和中位数pO₂。所有PET研究均使用ECAT EXACT 922/47扫描仪进行，轴向视野为16.2 cm。FMISO PET包括在静脉注射后120分钟对相关区域进行一次静态扫描。采集和重建参数如下：15分钟发射扫描和4分钟使用⁶⁸Ge棒源进行的透射扫描。静脉注射后68±11分钟对淋巴结转移灶进行FDG PET检查，应用全身工具，每个床位进行8分钟发射扫描和4分钟透射扫描。
为检测肿瘤缺氧的不同相关极谱测量参数与基于FMISO PET数据的氧合值之间的可能关系，计算了Pearson相关系数。发现2小时后FMISO的肿瘤与肌肉比值与缺氧分数参数（pO₂读数≤2.5、≤5.0和≤10.0 mmHg以及平均值和中位数）之间存在平均（r＞0.5）至高（r＞0.7）相关性。未发现FDG PET参数与极谱确定的肿瘤氧合状态之间存在相关性。
综上所述，FMISO摄取代表了宏观肿瘤部分的一个整体值。作为一种非侵入性测量方法，该方法似乎非常可行，可用于评估深部肿瘤的氧合状态。
