Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
J Gastroenterol. 2012 Feb;47(2):127-35. doi: 10.1007/s00535-011-0473-z. Epub 2011 Oct 8.
The purpose of this study was to analyze the detectability of colorectal neoplasia with fluorine-18-2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT).
Data for a total of 492 patients who had undergone both PET/CT and colonoscopy were analyzed. After the findings of PET/CT and colonoscopy were determined independently, the results were compared in each of the six colonic sites examined in all patients. The efficacy of PET/CT was determined using colonoscopic examination as the gold standard.
In all, 270 colorectal lesions 5 mm or more in size, including 70 pathologically confirmed malignant lesions, were found in 172 patients by colonoscopy. The sensitivity and specificity of PET/CT for detecting any of the colorectal lesions were 36 and 98%, respectively. For detecting lesions 11 mm or larger, the sensitivity was increased to 85%, with the specificity remaining consistent (97%). Moreover, the sensitivity for tumors 21 mm or larger was 96% (48/50). Tumors with malignant or high-grade pathology were likely to be positive with PET/CT. A size of 10 mm or smaller [odds ratio (OR) 44.14, 95% confidence interval (95% CI) 11.44-221.67] and flat morphology (OR 7.78, 95% CI 1.79-36.25) were significant factors that were associated with false-negative cases on PET/CT.
The sensitivity of PET/CT for detecting colorectal lesions is acceptable, showing size- and pathology-dependence, suggesting, for the most part, that clinically relevant lesions are detectable with PET/CT. However, when considering PET/CT for screening purposes caution must be exercised because there are cases of false-negative results.
本研究旨在分析氟-18-2-氟-2-脱氧-D-葡萄糖正电子发射断层扫描/计算机断层扫描（FDG-PET/CT）对结直肠肿瘤的检测能力。
共分析了 492 例同时接受 PET/CT 和结肠镜检查的患者的数据。在独立确定 PET/CT 和结肠镜检查的结果后，在所有患者检查的六个结肠部位中的每一个部位对结果进行了比较。以结肠镜检查为金标准确定 PET/CT 的疗效。
共在 172 例患者中通过结肠镜检查发现 270 个大小为 5 毫米或以上的结直肠病变，包括 70 个经病理证实的恶性病变。PET/CT 检测所有结直肠病变的敏感性和特异性分别为 36%和 98%。对于检测 11 毫米或更大的病变，敏感性增加至 85%，特异性保持不变（97%）。此外，21 毫米或更大的肿瘤的敏感性为 96%（48/50）。具有恶性或高级别病理的肿瘤很可能在 PET/CT 上呈阳性。10 毫米或更小的大小[比值比（OR）44.14，95%置信区间（95%CI）11.44-221.67]和平坦形态（OR 7.78，95%CI 1.79-36.25）是与 PET/CT 假阴性病例相关的重要因素。
PET/CT 检测结直肠病变的敏感性可以接受，表现出大小和病理依赖性，提示在大多数情况下，PET/CT 可检测到具有临床意义的病变。然而，在考虑将 PET/CT 用于筛查目的时必须谨慎，因为存在假阴性结果的情况。
