Abstract：
OBJECTIVE: The aim of this multicenter prospective study was to compare the sensitivity of 18F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) with that of 67Ga single photon emission computed tomography (SPECT) for the identification of the site of greatest importance for the final diagnosis of the cause of fever of unknown origin (FUO).
METHODS: The study participants consisted of patients with an axillary temperature ≥ 38.0 °C on ≥ 2 occasions within 1 week, with repeated episodes for ≥ 2 weeks prior to providing consent, and whose final diagnosis after undergoing specific examinations, including a chest-to-abdomen CT scan, was uncertain. All the patients underwent FDG-PET/CT imaging first, followed by 67Ga-SPECT imaging within 3 days. The results of the FDG-PET/CT and 67Ga-SPECT examinations were reviewed by the central image interpretation committee (CIIC), which was blinded to all other clinical information. The sensitivities of FDG-PET/CT and 67Ga-SPECT were then evaluated with regard to identifying the site of greatest importance for a final diagnosis of the cause of the fever as decided by the patient\'s attending physician. The clinical impacts (four grades) of FDG-PET/CT and 67Ga-SPECT on the final diagnosis were evaluated.
RESULTS: A total of 149 subjects were enrolled in this study between October 2014 and September 2017. No adverse events were identified among the enrolled subjects. Twenty-one subjects were excluded from the study because of deviations from the study protocol. Among the 128 remaining subjects, a final diagnosis of the disease leading to the appearance of FUO was made for 92 (71.9%) subjects. The final diagnoses in these 92 cases were classified into four groups: noninfectious inflammatory disease (52 cases); infectious disease (31 cases), malignancy (six cases); and other (three cases). These 92 subjects were eligible for inclusion in the study\'s analysis, but one case did not meet the PET/CT image acquisition criteria; thus, PET/CT results were analyzed for 91 cases. According to the patient-based assessments, the sensitivity of FDG-PET/CT (45%, 95% CI 33.1-58.2%) was significantly higher than that for 67Ga-SPECT (25%, 95% CI 15.5-37.5%) (P = 0.0029). The clinical impact of FDG-PET/CT (91%) was also significantly higher than that for 67Ga-SPECT (57%, P < 0.001).
CONCLUSIONS: FDG-PET/CT showed a superior sensitivity to 67Ga-SPECT for the identification of the site of greatest importance for the final diagnosis of the cause of FUO.
METHODS: The study participants consisted of patients with an axillary temperature ≥ 38.0 °C on ≥ 2 occasions within 1 week, with repeated episodes for ≥ 2 weeks prior to providing consent, and whose final diagnosis after undergoing specific examinations, including a chest-to-abdomen CT scan, was uncertain. All the patients underwent FDG-PET/CT imaging first, followed by 67Ga-SPECT imaging within 3 days. The results of the FDG-PET/CT and 67Ga-SPECT examinations were reviewed by the central image interpretation committee (CIIC), which was blinded to all other clinical information. The sensitivities of FDG-PET/CT and 67Ga-SPECT were then evaluated with regard to identifying the site of greatest importance for a final diagnosis of the cause of the fever as decided by the patient\'s attending physician. The clinical impacts (four grades) of FDG-PET/CT and 67Ga-SPECT on the final diagnosis were evaluated.
RESULTS: A total of 149 subjects were enrolled in this study between October 2014 and September 2017. No adverse events were identified among the enrolled subjects. Twenty-one subjects were excluded from the study because of deviations from the study protocol. Among the 128 remaining subjects, a final diagnosis of the disease leading to the appearance of FUO was made for 92 (71.9%) subjects. The final diagnoses in these 92 cases were classified into four groups: noninfectious inflammatory disease (52 cases); infectious disease (31 cases), malignancy (six cases); and other (three cases). These 92 subjects were eligible for inclusion in the study\'s analysis, but one case did not meet the PET/CT image acquisition criteria; thus, PET/CT results were analyzed for 91 cases. According to the patient-based assessments, the sensitivity of FDG-PET/CT (45%, 95% CI 33.1-58.2%) was significantly higher than that for 67Ga-SPECT (25%, 95% CI 15.5-37.5%) (P = 0.0029). The clinical impact of FDG-PET/CT (91%) was also significantly higher than that for 67Ga-SPECT (57%, P < 0.001).
CONCLUSIONS: FDG-PET/CT showed a superior sensitivity to 67Ga-SPECT for the identification of the site of greatest importance for the final diagnosis of the cause of FUO.
摘要：
目的：这项多中心前瞻性研究的目的是比较18F-氟脱氧葡萄糖（FDG）-正电子发射断层扫描/计算机断层扫描（PET/CT）与67Ga单光子发射计算机断层扫描（SPECT）的敏感性，以确定对最终诊断不明原因发热（FUO）的最重要部位。
方法：研究参与者包括1周内腋窝温度≥38.0°C的患者，在提供同意前反复发作≥2周，经过特殊检查后的最终诊断，包括胸部到腹部的CT扫描,不确定。所有患者均先行FDG-PET/CT显像,随后在3天内进行67Ga-SPECT成像。中央影像解读委员会(CIIC)对FDG-PET/CT和67Ga-SPECT检查结果进行了评审,对所有其他临床信息都是不知情的。然后评估FDG-PET/CT和67Ga-SPECT的敏感性，以确定对患者主治医师决定的发热原因的最终诊断最重要的部位。评估FDG-PET/CT和67Ga-SPECT对最终诊断的临床影响（四个等级）。
结果：2014年10月至2017年9月，本研究共纳入149名受试者。在登记的受试者中没有发现不良事件。由于与研究方案的偏差,21名受试者被排除在研究之外。在剩下的128个科目中，对92名(71.9%)受试者进行了导致FUO出现的疾病的最终诊断.92例患者的最终诊断分为四组：非感染性炎症性疾病（52例）；感染性疾病（31例），恶性肿瘤（6例）；和其他（3例）。这92名受试者有资格纳入研究分析，但有一例不符合PET/CT图像采集标准；因此，分析91例PET/CT检查结果。根据基于患者的评估，FDG-PET/CT的敏感性（45%，95%CI33.1-58.2%)显著高于67Ga-SPECT(25%，95%CI15.5-37.5%）（P=0.0029）。FDG-PET/CT的临床影响（91％）也显着高于67Ga-SPECT（57％，P<0.001)。
结论：FDG-PET/CT在鉴定对最终诊断FUO病因最重要的部位方面比67Ga-SPECT具有更高的敏感性。
方法：研究参与者包括1周内腋窝温度≥38.0°C的患者，在提供同意前反复发作≥2周，经过特殊检查后的最终诊断，包括胸部到腹部的CT扫描,不确定。所有患者均先行FDG-PET/CT显像,随后在3天内进行67Ga-SPECT成像。中央影像解读委员会(CIIC)对FDG-PET/CT和67Ga-SPECT检查结果进行了评审,对所有其他临床信息都是不知情的。然后评估FDG-PET/CT和67Ga-SPECT的敏感性，以确定对患者主治医师决定的发热原因的最终诊断最重要的部位。评估FDG-PET/CT和67Ga-SPECT对最终诊断的临床影响（四个等级）。
结果：2014年10月至2017年9月，本研究共纳入149名受试者。在登记的受试者中没有发现不良事件。由于与研究方案的偏差,21名受试者被排除在研究之外。在剩下的128个科目中，对92名(71.9%)受试者进行了导致FUO出现的疾病的最终诊断.92例患者的最终诊断分为四组：非感染性炎症性疾病（52例）；感染性疾病（31例），恶性肿瘤（6例）；和其他（3例）。这92名受试者有资格纳入研究分析，但有一例不符合PET/CT图像采集标准；因此，分析91例PET/CT检查结果。根据基于患者的评估，FDG-PET/CT的敏感性（45%，95%CI33.1-58.2%)显著高于67Ga-SPECT(25%，95%CI15.5-37.5%）（P=0.0029）。FDG-PET/CT的临床影响（91％）也显着高于67Ga-SPECT（57％，P<0.001)。
结论：FDG-PET/CT在鉴定对最终诊断FUO病因最重要的部位方面比67Ga-SPECT具有更高的敏感性。
