Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.
Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Rigshospitalet and University of Copenhagen, Copenhagen, Denmark.
J Nucl Med. 2017 Jul;58(7):1058-1064. doi: 10.2967/jnumed.116.175380. Epub 2017 Jan 12.
A fast-track pathway has been established in Denmark to investigate patients with serious nonspecific symptoms and signs of cancer (NSSC), who are not eligible to enter an organ-specific cancer program. The prevalence of cancer in this cohort is approximately 20%. The optimal screening strategy in patients with NSSC remains unknown. The aim of the study was to investigate whether F-FDG PET/CT was superior to CT as an initial imaging modality in patients with NSSC. In a randomized prospective trial, the imaging modalities were compared with regard to diagnostic performance. Two hundred patients were randomized 1:1 to whole-body F-FDG PET/CT or CT of the thorax and abdomen as the imaging modality. A tentative diagnosis was established after first-line imaging. The final referral diagnosis was adjudicated by the physician, when sufficient data were available. One hundred ninety-seven patients were available for analysis because 3 patients withdrew consent before scanning. Thirty-nine (20%) patients were diagnosed with cancer, 10 (5%) with an infection, 15 (8%) with an autoimmune disease, and 76 (39%) with other diseases. In the remaining 57 patients (28%), no specific disease was found. F-FDG PET/CT had a higher specificity (96% vs. 85%; = 0.028) and a higher accuracy (94% vs. 82%; = 0.017) than CT. However, there were no statistically significant differences in sensitivity (83% vs. 70%) or negative predictive values (96% vs. 92%). No difference in days to final referral diagnosis according to randomization group could be shown (7.2 vs. 7.6 d). However, for the subgroups in which the imaging modality showed a suggestion of malignancy, there was a significant delay to final diagnosis in the CT group compared with the F-FDG PET/CT group (11.6 vs. 5.7 d; = 0.02). Compared with CT, we found a higher diagnostic specificity and accuracy of F-FDG PET/CT for detecting cancer in patients with NSSC. F-FDG PET/CT should therefore be considered as first-line imaging in this group of patients.
丹麦建立了一条快速通道，用于调查患有严重非特异性癌症症状和体征（NSSC）且不符合特定器官癌症计划资格的患者。该队列中癌症的患病率约为 20%。NSSC 患者的最佳筛查策略仍不清楚。本研究旨在探讨 F-FDG PET/CT 是否优于 CT 作为 NSSC 患者的初始影像学检查方法。在一项随机前瞻性试验中，比较了两种影像学检查方法的诊断性能。200 名患者按 1:1 比例随机分为全身 F-FDG PET/CT 或胸部和腹部 CT 作为影像学检查方法。一线成像后建立暂定诊断。当有足够的数据时，由医生裁决最终转诊诊断。由于 3 名患者在扫描前撤回同意，因此有 197 名患者可进行分析。39 名（20%）患者被诊断为癌症，10 名（5%）患者为感染，15 名（8%）患者为自身免疫性疾病，76 名（39%）患者为其他疾病。在其余 57 名（28%）患者中，未发现特定疾病。与 CT 相比，F-FDG PET/CT 的特异性（96%对 85%； = 0.028）和准确性（94%对 82%； = 0.017）更高。然而，在敏感性（83%对 70%）或阴性预测值（96%对 92%）方面没有统计学差异。根据随机分组，无法显示最终转诊诊断的天数有差异（7.2 对 7.6 d）。然而，对于影像学检查提示恶性肿瘤的亚组，与 F-FDG PET/CT 组相比，CT 组的最终诊断明显延迟（11.6 对 5.7 d； = 0.02）。与 CT 相比，我们发现 F-FDG PET/CT 对 NSSC 患者癌症的诊断特异性和准确性更高。因此，F-FDG PET/CT 应作为该组患者的一线影像学检查方法。
