胃癌PET-CT显像的临床应用

目的：评价^18F-脱氧葡萄糖（FDG）PET-CT显像在胃癌诊断中的价值。方法：26例临床可疑胃癌及胃癌术后吻合口复发患者（男20例，女6例，年龄48～82岁）行全身^18F-FDG PET-CT扫描。患者于左手臂静脉注入^18F-FDG前行胃肠道喝水低张准备，患者行^18F-FDG PET-CT扫描前再次喝水充盈胃肠道。图像有2位核医学医师及2位影像学医师共同阅片。结果与病理结果及临床随访结果相对照。结果：^18F-FDG PET-CT扫描可同时得到PET、CT及PET-CT图像。PET图像发现病灶19例，PET-CT图像发现病灶20例，病理结果及临床随访结果证实原发性胃癌16例，胃癌术后吻合口复发3例，胃癌术后改变3例，胃炎4例。PET图像诊断胃癌及胃癌术后吻合口复发的灵敏性为89％，特异性为71％，准确性为85％，阳性预测值为89％，阴性预测值为71％；PET-CT图像诊断胃癌及胃癌术后吻合口复发的灵敏性为100％，特异性为86％，准确性为96％，阳性预测值为95％，阴性预测值为100％。结论：PET-CT在诊断胃癌及胃癌吻合口复发方面优越于PET图像。     

18F-FDG符合线路显像与异机CT图像融合诊断非小细胞肺癌复发转移的价值

目的 评价18F-脱氧葡萄糖(FDG)符合线路显像与异机CT图像融合诊断非小细胞肺癌(NSCLC)术后放化疗后复发转移的价值.方法 对可疑复发转移的40例NSCLC患者行18F-FDG符合线路显像,并于显像前后1周内行CT扫描.用三维(3D)图像融合软件进行图像融合.结果 在18F-FDG符合线路显像与CT扫描相同的范围内,40例患者共检出病灶58处,其中恶性52处,良性6处.融合图像诊断NSCLC复发转移的灵敏度、特异性、准确性、阳性预测值、阴性预测值、阳性似然比及阴性似然比分别为94.23%(49/52),5/6,93.10%(54/58),98.00%(49/50),5/8,5.65及0.07.图像融合灵敏度、准确性明显高于CT.单纯18F-FDG符合线路显像诊断效能与图像融合无差别,但与CT图像融合可明显提高对病灶的定位诊断(提高44.83%).结论 18F-FDG符合线路与CT图像融合诊断NSCLC术后放化疗后复发转移灵敏度高,定位准确,值得推广应用.     

~(18)F-FDGPET-CT在诊断卵巢癌术后腹膜后淋巴结转移中的价值

目的:评价18F-FDG PET-CT在卵巢癌术后腹膜后淋巴结转移中的诊断价值。方法:回顾性分析20例卵巢癌术后可疑腹膜后淋巴结转移患者的临床和影像资料,以病理及随访结果为标准,对照分析18 F-FDG PET-CT与常规影像学检查对腹膜后淋巴结转移的诊断结果。结果:腹膜后淋巴结转移灶在18F-FDG PET-CT上主要表现为病灶部分或全部呈放射性浓聚。PET-CT检查的敏感度、特异度、准确度、阳性预测值和阴性预测值分别为77.8%、77.8%、77.8%、91.3%、53.8%,常规影像学检查的敏感度、特异度、准确度、阳性预测值和阴性预测值分别为63.0%、33.3%、55.6%、73.9%、23.1%;二者比较,准确度差异具有统计学意义(P=0.046)。结论:18F-FDG PET-CT能准确诊断卵巢癌术后腹膜后淋巴结转移,具有重要的临床应用价值。     

18F-FDG PET-CT在卵巢癌术后监测中的应用

目的:探讨18氟-脱氧葡萄糖(18F-FDG)正电子发射计算机体层摄影(PET-CT)在卵巢癌术后监测中的应用价值。方法:16例卵巢癌患者经肿瘤细胞减灭术和术后化疗或放疗,临床完全缓解6个月以上。行18F-FDG PET-CT检查,结果与手术病理结果对照。结果:18F-FDG PET-CT发现了9例患者,有复发或转移,共发现病灶直径0.3~3.2cm 23处病灶。手术病理证实9例(56%)无假阳性,无假阴性,诊断准确率100%;诊断复发或转移灶的敏感性、特异性、准确率、阳性预测值和阴性预测值分别为78%、78%、78%、90%和58%。PET-CT显示与术中所见病灶的大小、部位均一致。结论:18F-FDGPET-CT在卵巢癌的术后监测中有很高的诊断价值。     

18F-FDG PET/CT在可疑神经系统副肿瘤综合征中的应用价值

目的 探讨18F-脱氧葡萄糖(FDG)PET/CT显像探测临床可疑神经系统副肿瘤综合征(PNS)患者潜在肿瘤病灶的应用价值.方法 回顾性分析20例可疑PNS患者18F-FDG PET/CT显像资料,对所有患者行随访病理检查或临床最终诊断,并将结果与PET/CT显像和随访结果进行比较.结果 20例中PET/CT显像发现可疑恶性病变或既往肿瘤复发和(或)转移者9例,阴性11例.9例阳性者中3例为假阳性.PET/CT显像对PNS恶性肿瘤检出的灵敏度、特异性、准确性、阳性预测值和阴性预测值分别为6/6,78.57%(11/14),85.00%(17/20),6/9和100.00%(11/11).6例真阳性中4例治疗方案得以修正,经抗肿瘤和免疫疗法后神经异常症状得到改善.结论 18F-FDG PET/CT显像在可疑PNS中的应用有积极意义,有助于发现恶性肿瘤,也能对肿瘤分期提供帮助.     

18F-FDG PET/CT在可疑神经系统副肿瘤综合征中的应用价值

目的 探讨18F-脱氧葡萄糖（FDG）PET/CT显像探测临床可疑神经系统副肿瘤综合征（PNS）患者潜在肿瘤病灶的应用价值.方法 回顾性分析20例可疑PNS患者18F-FDG PET/CT显像资料,对所有患者行随访病理检查或临床最终诊断,并将结果与PET/CT显像和随访结果进行比较.结果 20例中PET/CT显像发现可疑恶性病变或既往肿瘤复发和（或）转移者9例,阴性11例.9例阳性者中3例为假阳性.PET/CT显像对PNS恶性肿瘤检出的灵敏度、特异性、准确性、阳性预测值和阴性预测值分别为6/6,78.57%（11/14）,85.00%（17/20）,6/9和100.00%（11/11）.6例真阳性中4例治疗方案得以修正,经抗肿瘤和免疫疗法后神经异常症状得到改善.结论 18F-FDG PET/CT显像在可疑PNS中的应用有积极意义,有助于发现恶性肿瘤,也能对肿瘤分期提供帮助.     

18F-FDG PET/CT在可疑神经系统副肿瘤综合征中的应用价值

目的 探讨18F-脱氧葡萄糖(FDG)PET/CT显像探测临床可疑神经系统副肿瘤综合征(PNS)患者潜在肿瘤病灶的应用价值.方法 回顾性分析20例可疑PNS患者18F-FDG PET/CT显像资料,对所有患者行随访病理检查或临床最终诊断,并将结果与PET/CT显像和随访结果进行比较.结果 20例中PET/CT显像发现可疑恶性病变或既往肿瘤复发和(或)转移者9例,阴性11例.9例阳性者中3例为假阳性.PET/CT显像对PNS恶性肿瘤检出的灵敏度、特异性、准确性、阳性预测值和阴性预测值分别为6/6,78.57%(11/14),85.00%(17/20),6/9和100.00%(11/11).6例真阳性中4例治疗方案得以修正,经抗肿瘤和免疫疗法后神经异常症状得到改善.结论 18F-FDG PET/CT显像在可疑PNS中的应用有积极意义,有助于发现恶性肿瘤,也能对肿瘤分期提供帮助.     

18F-FDG符合线路SPECT显像联合CT、B超、MRI在结直肠癌术后复发及转移中的诊断价值

目的探讨18F-FDG 符合线路 SPECT 显像联合传统显像(CT、B 超、MRI)在结直肠癌术后复发及转移中的诊断价值.资料与方法107例结直肠癌术后患者行18F-FDG 符合线路 SPECT 显像,并联合 CT、B 超、MRI 诊断结直肠癌术后复发及转移.结果107例患者最终确定复发及转移共29例.18F-FDG 符合线路 SPECT 显像与传统显像诊断均为阳性的15例患者中,传统显像检出病灶20个,符合线路 SPECT 显像检出病灶26个.传统显像检出3个符合线路 SPECT 显像未发现的转移病灶,而符合线路 SPECT 显像检出9个传统显像未发现的病灶.18F-FDG 符合线路 SPECT 显像诊断结直肠癌术后复发及转移的灵敏度、特异性和准确率分别为79.3%、89.7%和86.9%;传统显像的诊断效能分别为62.1%、88.5%和81.3%;二者联合的诊断效能分别为89.7%、92.3%和91.6%.二者联合诊断结直肠癌术后复发及转移的灵敏度和准确率明显优于传统显像(P <0.05).结论18F-FDG 符合线路 SPECT 显像联合 CT、B 超、MRI 在监测结直肠癌术后复发及转移中具有重要临床价值.     

18F-FDG PET/CT显像在宫颈癌术后复发和转移中的应用价值

目的 探讨18F-FDG PET/CT显像在宫颈癌术后复发和转移中的应用价值.方法 搜集临床可疑宫颈癌术后复发和转移患者65例,年龄23～77岁,平均48.7岁.所有宫颈癌患者均经手术病理确诊并行根治性治疗,其中鳞癌47例,腺癌12例,腺鳞癌4例,透明细胞癌1例,小细胞癌1例.患者均行18F-FDG PET/CT全身显像检查,采用目测法和半定量法判断结果,并与组织病理或临床随访结果比较其诊断的准确性,以及评价其诊断的真实性和可靠性.结果 65例患者经组织病理或临床随访证实50例复发和转移.18F-FDG PET/CT显像诊断肿瘤局部复发18例,肿瘤转移33例,复发和转移病灶的SUVmax 2.91 ～ 16.70,平均SUVmax 9.81,18F-FDG PET/CT显像诊断宫颈癌术后复发和转移的灵敏度为98.00％,特异性为86.67％,准确性为95.38％,阳性预测值为96.08％,阴性预测值为92.86％;18F-FDG PET/CT显像诊断结果与组织病理或临床随访结果比较差异无统计学意义(经x2检验,P＞0.05);二者结果的吻合度有统计学意义且吻合度较强(系数k=0.867,P=0.000).结论 18F-FDG PET/CT显像能够准确、直观地显示宫颈癌术后复发和转移,且真实性和可靠性好;同时18F-FDG PET/CT全身显像检查是肿瘤远处转移探测最有效的方法,可较全面评估患者病情,对协助临床确定个体化治疗方案具有重要价值.     

18F-FDG PET-CT在探测卵巢癌术后复发与转移中的应用价值

目的 探讨18F-FDG PET-CT在探测和诊断卵巢癌术后复发、转移中的应用价值.方法 回顾性分析65例卵巢癌术后患者的全身PET-CT结果.临床随访时间为3～ 57个月.确诊卵巢癌是否复发或转移的依据为手术病理学检查、多种影像学检查和临床随访.结果 65例患者中,55例有肿瘤复发、转移,10例无肿瘤复发.65例卵巢癌患者中,PET-CT图像共显示阳性灶180个,最后经手术病理或临床随访确诊为复发和转移的病灶为165个,另15个病灶为淋巴结反应性增生;18F-FDG PET-CT真阳性51例、假阳性1例、假阴性4例、真阴性9例,18F-FDG PET-CT对卵巢癌患者检出的灵敏度、特异度、准确率、阳性预测值和阴性预测值分别为92.7％ (51/55)、90.0％(9/10)、93.8％(61/65)、98.1％(51/52)、69.2％(9/13).糖类抗原125 (CA125)水平与18F-FDG PET结果有较高的相关性,47例患者的CA125升高,其中,44例患者PET-CT阳性,PET-CT阳性率为93.6％.结论 PET-CT全身显像在检测卵巢癌术后复发和转移病灶方面具有较高的灵敏度和准确率,能够使卵巢癌术后再次分期更准确、更全面.同时,CA125升高时,PET-CT全身检查在发现隐匿及远处转移病灶方面具有明显优势,可为临床进一步诊治提供依据.     

Whole-Body FDG-PET in Patients with Recurrent Colorectal Carcinoma. A Comparative Study with CT

Purpose: To assess the clinical accuracy of whole-body 2-[F-18]-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) in the diagnosis of recurrent colorectal carcinoma in comparison to conventional computed tomography (CT).Materials and methods: Forty patients with suspected recurrent colorectal carcinoma based on either progressive serial carcinoemrbyonic antigen (CEA) serum elevation or positive/equivocal CT findings underwent whole-body FDG-PET. PET results were compared with those of CT and correlated to the final histopathological and clinical findings.Results: A final diagnosis was obtained at 93 sites in 35 patients by histology and in 5 patients by clinical follow up of at least 6 months. Of the 93 sites, 53 were determined to be malignant and 40 benign. FDG-PET evaluated on a 5-point scale (0-4) showed a positive and negative predictive value in the range of 96-98% and 83-93% respectively as the threshold for positivity was moved from 0 through 3. By comparison, CT, also evaluated on a 5-point scale showed a positive and negative predictive value in the range of 75-88% and 67-71% respectively. The area under the fitted receiver operating characteristic curve for PET: A(PET) = 0.96 +/- 0.02 was significantly greater (P < 0.001) than that observed for CT: A(CT) = 0.77 +/- 0.06. The distribution of maximum standardized uptake value (SUVmax) showed that all negative lesions have SUVmax below 5.0 whereas 75% of positive lesions were above 5.0 pointing to the fact that disease positivity is more likely in lesions with high SUV values.Conclusion: The results of this study confirm that whole-body FDG-PET is more accurate than conventional CT in the staging of patients with suspected recurrent colorectal carcinoma.     

Clinical Impact of 18F-FDG-PET in the Suspicion of Recurrent Ovarian Carcinoma Based on Elevated Tumor Marker Serum Levels

Purpose: To retrospectively evaluate the contribution of 18F-fluorodeoxy-glucose-positron emission tomography (FDG-PET) to the diagnosis and clinical management of patients who were suspected of recurrent ovarian carcinoma, based on elevated tumor markers levels with normal or equivocal computed tomography (CT) or nuclear magnetic resonance (NMR).Procedures: 20 patients with these characteristics underwent FDG-PET. PET findings were confirmed in 14, in 7 by surgery, and in the other 7 by clinical course.Results: Recurrence was confirmed in 12 patients, all with FDG-PET positive. In other 2, recurrence was rule out and in 1, FDG-PET was negative. FDG-PET accuracy was 93% with 4 surgeries avoided and guided other 6.Conclusions: FDG-PET is an useful technique for detecting recurrent ovarian carcinoma suspected by elevated tumor markers levels and normal or equivocal results in the morphologic imaging techniques and has an important clinical impact on the management of these patients.     

The impact of FDG-PET on the management algorithm for recurrent colorectal cancer.

Positron emission tomography (PET) has been successfully used to image colorectal cancer (CRC). This study evaluated the accuracy of 2-[(18)F]-fluoro-2-deoxy- D-glucose (FDG) PET for the detection and staging of recurrent CRC and the consequent impact on clinical management. Forty-two patients previously treated for CRC were investigated for suspected recurrence and, if recurrence was confirmed, the extent of disease was evaluated. All patients underwent whole-body FDG-PET and computed tomography (CT) scan and results were compared to assess sensitivity, specificity and diagnostic accuracy for each modality. We then assessed the FDG-PET directed alteration in clinical management from that planned on the basis of spiral CT results. FDG-PET was more sensitive (93%) than CT (73%) for detection of recurrence (specificity 58% and 75%, respectively). FDG-PET yielded a correct diagnosis in 35 (83%) out of 42 patients, while CT did so in 31 patients (74%). FDG-PET was more accurate than CT for staging local recurrence (sensitivity 100%, specificity 86% with FDG-PET vs 75% and 100%, respectively, with CT) and CRC liver metastases (sensitivity 100% vs 45%; specificity 100% for both). Overall, PET upstaged 8 out of 30 patients (27%) and altered patient management in 16 (38%) cases. This study confirms that FDG-PET is more sensitive than CT for the detection and staging of recurrent CRC. The results also indicate that FDG-PET is an accurate means of selecting appropriate patients for operative treatment. When applied to routine clinical practice, patient management is altered.     

PET/CT using 18F-FDG in suspected lung cancer recurrence: diagnostic value and impact on patient management.

The goal of this study was to assess the value of hybrid imaging using a combined PET/CT device with 18F-FDG in the diagnosis and clinical management of suspected recurrent lung cancer. METHODS: Forty-two patients with non-small cell lung cancer (NSCLC) with suspected recurrence due to new clinical, biochemical, and radiologic findings were prospectively evaluated. PET/CT results were compared with PET interpreted with side-by-side CT data. A final diagnosis of recurrence was confirmed by histologic tissue sampling during surgery or biopsy or by further clinical and radiologic work-up. The impact of PET/CT on patient management was assessed. RESULTS: Twenty-four of 27 positive PET/CT studies (89%) were proven to have recurrent disease. Fourteen of 15 negative PET/CT studies (93%) had no evidence of disease. The sensitivity, specificity, and positive and negative predictive values of PET/CT for diagnosis of recurrence were 96%, 82%, 89%, and 93% compared with 96%, 53%, 75%, and 90%, respectively, for PET. PET/CT changed the PET lesion classification in 22 patients (52%), by determining the precise localization of sites of increased 18F-FDG uptake. PET/CT changed the management of 12 patients (29%) by eliminating previously planned diagnostic procedures (5 patients), by initiating a previously unplanned treatment option (4 patients), or by inducing a change in the planned therapeutic approach (3 patients). CONCLUSION: In patients with a suspected recurrence of NSCLC, PET/CT provides a better anatomic localization of suspicious lesions compared with PET interpreted with side-by-side CT data. This improved diagnostic performance of PET/CT has a further impact on the clinical management and treatment planning of the patients.     

Role of (18)F-FDG dual-head gamma-camera coincidence imaging in recurrent or metastatic colorectal carcinoma.

(18)F-FDG PET has been shown to be of high diagnostic accuracy for the evaluation of recurrent colorectal cancer. However, the limited availability of PET scanners precludes (18)F-FDG assessment of many patients for whom the study is indicated. An alternative is the SPECT system in coincidence mode. The aim of this study was to determine the role of dual-head camera (18)F-FDG coincidence imaging (DHC (18)F-FDG) in patients with recurrent colorectal cancer. METHODS: Sixty-seven DHC (18)F-FDG studies were performed on 62 patients with suspected recurrent colorectal cancer. Reports of contemporary CT were available for the purpose of correlation for 61 of the studies. The final diagnosis of the imaging findings was based on histology or clinical and imaging follow-up of at least 6 mo. RESULTS: In lesion-based analysis, 103 tumor sites were suspected on DHC (18)F-FDG, CT, or colonoscopy. Ninety-three of them were found to be true tumor sites. For DHC (18)F-FDG, the sensitivity was 88%, specificity was 80%, positive predictive value (PPV) was 98%, negative predictive value (NPV) was 42%, and accuracy was 87%. For CT, the sensitivity was 63%, specificity was 10%, PPV was 85%, NPV was 3%, and accuracy was 57%. In patient-based analysis, DHC (18)F-FDG differentiated patients with recurrent cancer from disease-free patients with a sensitivity of 91%, specificity of 73%, PPV of 94%, NPV of 62%, and accuracy of 88%. DHC (18)F-FDG detected tumor sites in 12 (67%) of 18 patients with elevated carcinoembryonic antigen and negative CT findings. CONCLUSION: DHC (18)F-FDG is an adequate readily available technique for assessment of recurrent colorectal cancer and has a diagnostic accuracy better than that of CT.     

FDG-PET improves the staging and selection of patients with recurrent colorectal cancer

Whole-body fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) has proved effective in the diagnosis and staging of recurrent colorectal cancer. In this study, we analysed how PET affects the management of patients with recurrent colorectal cancer by permitting more accurate selection of candidates for curative resection. The data of 79 patients with known or suspected recurrent colorectal cancer were analysed. Conventional imaging modalities (CIM) and PET results were compared with regard to their accuracy in determining the extent and the resectability of tumour recurrence. Recurrence was demonstrated in 68 of the 79 patients. The data indicate that PET was superior to CIM for detection of recurrence at all sites except the liver. Based on the CIM+PET staging, surgery with curative intent was proposed in 39 patients and was indeed achieved in 31 of them (80%). PET was more accurate than CIM alone in predicting the resectability or non-resectability of the recurrence (82% vs 68%, P=0.02). It is concluded that whole-body FDG-PET is highly sensitive for both the diagnosis and the staging of patients with recurrent colorectal cancer. Its use in conjunction with conventional imaging procedures results in a more accurate selection of patients for surgical treatment with curative intent.     

Early diagnosis of recurrent breast cancer with FDG-PET in patients with progressive elevation of serum tumor markers.

BACKGROUND: The aim of this work is to assess the diagnostic value of positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG), in the early detection of tumour recurrence in already treated breast cancer patients in apparent complete remission and with a progressive elevation of tumour markers CEA and/or CA 15.3 without any other clinical or instrumental signs of relapses. METHODS: The author studied 45 women (mean age 58+/-12, range 35-80 years) with histological diagnosis of breast cancer who underwent a tumour marker-guided whole body FDG-PET. All patients were in remission, without any other clinical or instrumental signs of relapses, except for the progressive elevation of CA 15.3 and/or CEA, tested during the follow-up. FDG-PET results were controlled by pathology when histological sampling was possible, by other conventional imaging modalities (US, X-rays, CT, MRI) and/or by clinical follow-up up to 12 months at least. RESULTS: FDG-PET findings were evaluated in 38 patients: 27 resulted positive. Among these 27 PET positive patients 24 were true positive and 3 false positive. Tumour marker guided FDG-PET was also able to discover 3 unknown neoplasms not visualized by other modalities. PET revealed 54 sites of intense focal FDG uptake. The anatomical distribution of these sites was 19 skeleton, 18 lymph node basins, 5 liver, 5 pelvic region, 1 lung, 1 pericardium, 1 pleura, 1 contralateral breast, 2 peritoneum and 1 thyroid bed. Forty-eight of these 54 sites of FDG accumulation were confirmed to be metastases. FDG-PET resulted negative in 11 patients and only in 2 of them the other diagnostic modalities were able to discover metastatic lesions; we had 9 true negative and 2 false positive RESULTS. On the basis of our investigation the performances of tumour marker guided FDG-PET per patient are as follows: sensitivity 92% (24/26), specificity 75% (9/12), positive predictive value 89% (24/27), negative predictive value 82% (9/11), accuracy 87% (33/38). CONCLUSIONS: This study demonstrated the clinical utility of tumour marker-guided PET in the follow-up of breast cancer patients. This diagnostic approach allowed to modify the clinical management in those patients in whom a tumor relapse or unexpected primary neoplasm was discovered.     

Stellenwert der PET/CT zur Bildgebung des kolorektalen Karzinoms

CLINICAL/METHODICAL ISSUE: Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) has emerged as a very useful imaging modality in the management of colorectal carcinoma. Data from the literature regarding the role of PET/CT in the initial diagnosis, staging, radiotherapy planning, response monitoring and surveillance of colorectal carcinoma is presented. Future directions and economic aspects are discussed. STANDARD RADIOLOGICAL METHODS: Computed tomography (CT), magnetic resonance imaging (MRI) and FDG-PET for colorectal cancer and endorectal ultrasound for rectal cancer. METHODICAL INNOVATIONS: Combined FDG-PET/CT. PERFORMANCE: While other imaging modalities allow superior visualization of the extent and invasion depth of the primary tumor, PET/CT is most sensitive for the detection of distant metastases of colorectal cancer. ACHIEVEMENTS: We recommend a targeted use of PET/CT in cases of unclear M staging, prior to metastasectomy and in suspected cases of residual or recurrent colorectal carcinoma with equivocal conventional imaging. The role of PET/CT in radiotherapy planning and response monitoring needs to be determined. Currently there is no evidence to support the routine use of PET/CT for colorectal screening, staging or surveillance. PRACTICAL RECOMMENDATIONS: To optimally exploit the synergy between morphologic and functional information, FDG-PET should generally be performed as an integrated FDG-PET/CT with a contrast-enhanced CT component in colorectal carcinoma.     

18F-FDG PET/CT全身显像在原发灶不明转移癌中的临床应用

目的 探讨18F-脱氧葡萄糖(FDG)PET/CT全身显像在原发灶不明转移癌(CUP)诊断中的临床应用价值.方法 回顾性分析2006年1月至2007年6月2589例18F-FDG PET/CT显像患者中169例CUP患者的显像结果,通过分析病历记录、病理检查结果及临床随访确定最终原发灶诊断结果.结果 169例CUP患者中19例失访,150例有完整资料.70例成功探测到原发灶,总检出率为46.7%(70/150),其中52例得到病理检查证实,18例为临床诊断;肺癌38例,占54.3%,鼻咽癌8例,占11.4%,消化系统肿瘤13例,占18.6%,其他肿瘤11例,占15.7%.3例临床怀疑转移瘤,18F-FDG PET/CT未见明显恶性征象,经随访证实为良性病变.6例PET/CT诊断错误.15例患者没有确诊.56例未探测到原发灶,其中3例在随访过程中得到确诊,分别为鼻咽癌、膀胱癌、食管癌各1例.结论 18F-FDG PET/CT全身显像对诊断CUP具有重要临床价值.     

The utility of FDG-PET/CT as an effective tool for detecting recurrent colorectal cancer regardless of serum CEA levels

Purpose

Tumor recurrence of colorectal cancers (CRC) is generally followed up by analyses of the serum carcinoembryonic antigen (CEA) levels. However, recent evidence suggests that tumor recurrence can also be visualized by 18F-fluoro-deoxyglucose emission tomography/computed tomography (FDG-PET/CT) in patients with normal CEA levels. We retrospectively evaluated the diagnostic performance of FDG-PET/CT in patients with suspected recurrence of CRC by comparing PET/CT performance in patients with normal CEA levels with PET/CT performance in patients with elevated CEA levels.

Methods

A total of 235 patients with CRC who had been treated with surgery and/or chemotherapy/radiotherapy underwent PET/CT for the detection of tumor recurrence. The patients [96 females and 139 males; age (mean?±?SD) 59.9?±?12.6?years; range 18?C85] were divided into 2 groups based on whether their CEA levels were normal (<5?ng/ml) (Group 1, n?=?118) or elevated (>5?ng/ml) (Group 2, n?=?117). All of the patients had suspected recurrence based on raised CEA levels, clinical symptoms, and/or tumor detection using other imaging modalities.

Results

Of the 235 patients, 172 (73.1?%) had disease recurrence confirmed by a pathological examination (either biopsy or surgical exploration) or clinical follow-up studies. The FDG-PET/CT study yielded a true positive in detecting recurrence in 169 (71.9?%) patients, a true negative in 53 (22.5?%) patients, a false negative in 3 (1.2?%) patients and a false positive in 10 (4.2?%) patients. CRC recurrence was detected in 64.4?% (76/118) and 88?% (103/117) patients in Group 1 and Group 2 with FDG-PET/CT, respectively. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of the FDG-PET/CT study for establishing recurrence were 100, 84, 89.4, 100 and 93.2?%, respectively, for Group 1; by contrast, these parameters were 97.1, 84.6, 98, 78.5 and 95.7?%, respectively, for Group 2. The number of patients with hepatic and extra-hepatic metastases, such as lung and abdominal lymph node metastasis, detected with FDG-PET/CT was significantly different in Group 1 than in Group 2; however, the number of patients with local recurrence and peritoneal implants detected with FDG-PET/CT was not different between the two groups.

Conclusions

FDG-PET/CT can accurately detect tumor recurrence in patients with suspected recurrent CRC, even for patients with normal CEA levels.