Department of Radiation Oncology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
PLoS One. 2013 Nov 12;8(11):e75159. doi: 10.1371/journal.pone.0075159. eCollection 2013.
To determine the optimal standardized uptake value (SUV) of (18)F-fluorodeoxyglucose ((18)F-FDG) for positron emission tomography (PET) imaging, at which the PET-defined gross tumor volume (GTVPET) best matches with the pathological volume (GTVPATH) in the cervical cancer.
Ten patients with the cervical cancer who underwent surgery were enrolled in this study. The excised specimens were processed for whole-mount serial sections and H-E staining. The tumor borders were outlined in sections under a microscope, histopathological images were scanned and the GTVPATH calculated. The GTVPET was delineated automatically by using various percentages relative to the maximal SUV and absolute SUV. The optimal threshold SUV was further obtained as the value at which the GTVPET best matched with the GTVPATH.
An average of 85 ± 10% shrinkage of tissue was observed after the formalin fixation. The GTVPATH was 13.38 ± 2.80 cm(3) on average. The optimal threshold on percentile SUV and absolute SUV were 40.50% ± 3.16% and 7.45 ± 1.10, respectively. The correlation analysis showed that the optimal percentile SUV threshold was inversely correlated with GTVPATH (p<0.05) and tumor diameter (p<0.05). The absolute SUV was also positively correlated with SUVmax (p<0.05).
The pathological volume could provide the more accurate tumor volume. The optimal SUV of FDG for PET imaging by use of GTVPATH as standard for cervical cancer target volume delineation was thus determined in this study, and more cases are being evaluated to substantiate this conclusion.
确定正电子发射断层扫描（PET）成像中（18）F-氟代脱氧葡萄糖（（18）F-FDG）的最佳标准化摄取值（SUV），在此 SUV 值下，PET 定义的大体肿瘤体积（GTVPET）与宫颈癌的病理体积（GTVPATH）最佳匹配。
本研究纳入了 10 名接受手术治疗的宫颈癌患者。切除的标本进行全距连续切片和 H-E 染色。在显微镜下对切片中的肿瘤边界进行勾画，扫描组织病理学图像并计算 GTVPATH。通过使用与最大 SUV 和绝对 SUV 相关的各种百分比自动勾画 GTVPET。进一步获得最佳阈值 SUV，作为 GTVPET 与 GTVPATH 最佳匹配的 SUV 值。
福尔马林固定后组织平均收缩 85±10%。GTVPATH 平均为 13.38±2.80cm3。百分比 SUV 和绝对 SUV 的最佳阈值分别为 40.50%±3.16%和 7.45±1.10。相关性分析表明，最佳百分比 SUV 阈值与 GTVPATH（p<0.05）和肿瘤直径（p<0.05）呈负相关。绝对 SUV 与 SUVmax 也呈正相关（p<0.05）。
病理体积可以提供更准确的肿瘤体积。本研究确定了基于 GTVPATH 作为宫颈癌靶区勾画标准的 FDG PET 成像最佳 SUV，正在评估更多病例以证实这一结论。
