Colorectal Surgical Unit, Northern General Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, South Yorkshire, UK.
Colorectal Dis. 2012 Feb;14(2):e56-63. doi: 10.1111/j.1463-1318.2011.02760.x.
(18)Fluorodeoxyglucose ((18)FDG) positron emission tomography/computed tomography (PET/CT) is an established part of staging in a wide variety of malignancies. Incidental abnormal uptake of (18)FDG of unknown significance is frequently encountered. Therefore, we investigated patients with abnormal colonic uptake of (18)FDG, determined by PET/CT images, using colonoscopy.
The radiology reports of all patients referred to a tertiary referral centre for a PET/CT scan were reviewed retrospectively. Patients with abnormal colonic uptake of (18)FDG were identified and the PET/CT findings were correlated with colonoscopic findings.
Of 555 consecutive patients identified over a 26-month period, 53 had abnormal colonic uptake of (18)FDG, as determined by PET/CT images. Twenty-nine were not investigated following discussion in a specialist multidisciplinary (MDT) meeting, according to local protocol. Twenty out of 24 patients investigated by endoscopy had a colonic lesion correlating to the site identified on the PET/CT image: 16 patients had tubulovillous adenomas (nine of which were > 10 mm), two had invasive adenocarcinomas, two had diverticular disease and one had collagenous colitis; no colonic lesion was detected in three. These findings were incidental and not related to the primary diagnosis for which the scan was being performed. Accordingly, a positive predictive value of 83% is associated with the finding of abnormal uptake of (18)FDG on PET/CT images.
Incidental abnormal colonic uptake of (18)FDG, determined by a PET/CT scan requires definitive colonic investigation in patients suitable for further treatment because significant colonic pathology is frequently identified. The benefit of this approach should be discussed in specialist MDT meetings and tailored to each patient; however, national guidelines for management are required.
（18）氟脱氧葡萄糖（（18）FDG）正电子发射断层扫描/计算机断层扫描（PET/CT）是广泛各种恶性肿瘤分期的既定组成部分。经常遇到无法确定意义的（18）FDG 摄取异常。因此，我们通过 PET/CT 图像研究了因异常摄取（18）FDG 而被转诊至三级转诊中心的患者，并进行了结肠镜检查。
回顾性审查了在 26 个月期间转诊至三级转诊中心进行 PET/CT 扫描的所有患者的放射学报告。确定了（18）FDG 摄取异常的患者，并将 PET/CT 结果与结肠镜检查结果相关联。
在 555 例连续患者中，有 53 例（18）FDG 摄取异常，根据 PET/CT 图像确定。根据当地协议，在一次多学科专家（MDT）会议上讨论后，有 29 例未进行调查。对 24 例接受内镜检查的患者进行了研究，发现与 PET/CT 图像上识别的部位相对应的结肠病变：16 例患者有管状绒毛状腺瘤（其中 9 例大于 10 毫米），2 例患者有侵袭性腺癌，2 例患者有憩室疾病，1 例患者有胶原性结肠炎；3 例患者未发现结肠病变。这些发现是偶然的，与进行扫描的主要诊断无关。因此，（18）FDG 在 PET/CT 图像上摄取异常的阳性预测值为 83%。
因 PET/CT 扫描而确定的偶然异常的（18）FDG 摄取需要对适合进一步治疗的患者进行明确的结肠检查，因为经常发现重要的结肠病理学。这种方法的益处应在专家 MDT 会议上进行讨论，并针对每个患者进行调整；但是，需要制定国家管理指南。
