符合线路显像在大肠癌术后复发转移中的临床应用

目的：探讨符合线路显像在大肠癌术后复发转移中的临床应用价值。方法：对31例临床怀疑复发转移的大肠癌术后患者行^18F-脱氧葡萄糖(FDG)符合线路显像，计算其诊断准确性、灵敏度、特异性、阳性预测值、阴性预测值及其95％可信区间，并与B超、CT、MRI的诊断结果相比较。结果:31例大肠癌术后患者中显像阳性19例，假阴性2例，无假阳性。其诊断准确性、灵敏度、特异性、阳性预测值、阴性预测值分别为93．5％，90．5％，100％，100％，83．3％；其95％可信区间为78％～99％，70％-99％，69％-100％，82％-100％，69％-100％。符合线路显像的诊断准确性明显高于B超和CT，灵敏度和阴性预测值明显高于B超；95％可信区间分析结果示符合线路显像高于B超、CT和MRI。结论:^18F-FDG符合线路显像对大肠癌术后复发转移的诊断有较高的临床应用价值。     

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.     

18F-FDGSPECT/CT显像在鼻咽癌治疗后EBV-DNA升高患者中的应用

目的:探讨18F-FDG SPECT/CT显像在检测鼻咽癌治疗后血清EBV-DNA升高患者,肿瘤复发和(或)转移病灶的价值.方法:鼻咽癌治疗后血清EBV-DNA升高患者45例,皆行全身18F-FDG SPECT/CT显像.所有图像经图像融合后,进行18F-FDG显像图像和CT图像帧对帧对比分析.肿瘤复发和(或)转移病灶根据病理检查结果、多种影像学诊断及临床随访而确诊.随访时间均＞6个月.采用SPSS 11.5软件进行统计学处理,进行x2检验.结果:45例患者中,明确诊断肿瘤复发和(或)转移者35例,单纯CT诊断肿瘤复发和(或)转移28例,其灵敏度为80.0％ (28/35);符合线路18F-FDG CT同机融合显像诊断肿瘤复发和(或)转移32例,灵敏度提高至91.4％ (32/35).结论:18F-FDG SPECT/CT在检测鼻咽癌治疗后EBV-DNA升高患者肿瘤复发和(或)转移病灶中有较好的应用价值.但角化型鼻咽癌可能出现假阴性.     

~(18)F-FDG符合线路显像在喉癌中的应用价值

目的:探讨18F-FDG符合线路显像在喉癌中的应用价值。方法:30例经病理证实的喉癌患者术前行18F-FDG双探头符合线路显像及CT检查。其中28例行手术治疗,以术后病理检查结果作为"金标准",比较18F-FDG符合线路显像及CT检查在原发肿瘤、淋巴结及远处转移(TNM)中的价值。结果:18F-FDG与CT探测淋巴结病变的灵敏度为75.00%和62.50%,特异性78.26%和43.48%,准确性76.36%和54.55%,阴性预测值69.23%和45.45%,阳性预测值82.76%和60.61%,其中特异性、准确性差异有统计学意义(P0.05)1。8F-FDG符合线路显像发现2例有远处转移,改变了治疗方案。结论:18F-FDG符合线路显像在喉癌术前分期和治疗方案的制定中具有较好的临床应用价值。     

肺部病变18F-FDGSPECT符合线路显像

目的:探讨18F-FDG SPECT符合线路显像对肺部病变的定性诊断价值。材料和方法:用双探头SPECT符合线路对肺部病变患者进行18F-FDG肿瘤代谢显像,分析检查结果并与CT进行比较。结果:48例肺部病变患者18F-FDG显像诊断结果为真阳性37例,真阴性7例,假阳性3例和假阴性1例。其诊断的准确率、灵敏度和特异性分别为91.7％,97.4％和70％。诊断准确率显著高于CT检查。结论:18F-FDG SPECT符合线路显像对肺部病变具有较高的定性诊断价值。     

18F-FDG符合线路显像诊断骨转移瘤的价值及与99Tcm-MDP骨显像的比较

目的 评价^18F-脱氧葡萄糖(FDG)符合线路显像在骨转移瘤诊断中的价值，并与^99Tc^m-亚甲基二膦酸盐(MDP)骨显像进行比较。方法因怀疑恶性肿瘤或骨转移而行^18F-FDG符合线路显像者55例，41例于^18F-FDG检查前后4周内进行了^99Tc^m-MDP全身骨显像。其中30例骨转移瘤患者，15例无骨转移瘤，10例^18F-FDG显像示可疑肿瘤直接骨侵犯(单独进行分析)。结果 ^18F-FDG符合线路显像和骨显像对骨转移瘤的灵敏度、特异性、阳性预测值、阴性预测值、诊断准确性分别为100％，93％，97％，100％，98％和95％，50％，75％，86％，77％，前者特异性、阳性预测值、诊断准确性显著高于骨显像(P=0．024，0．035，0．007)；^18F-FDG显像发现30例骨转移瘤患者中的20例有骨外原发或转移肿瘤。10例^18F-FDG显像示可疑肿瘤直接骨侵犯患者中，4例被证实有骨受累，6例无骨受累，而骨显像对骨受累情况均作出了正确判断。结论 ^18F-FDG符合线路显像对骨转移瘤的诊断有较高的灵敏度和特异性，并能发现骨外原发或转移性肿瘤；^99Tc^m-MDP骨显像对骨转移瘤也有较高的灵敏度，但特异性较差。     

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符合线路显像对食管癌术后复发转移的诊断价值

目的 探讨^18F-脱氧葡萄糖（FDG）符合线路显像对食管癌术后复发转移的诊断价值。方法 对29例临床怀疑复发转移的食管鳞状细胞癌术后患者行^18F-FDG符合线路显像，计算其诊断复发转移灶的灵敏度、特异性和准确性，并与CT诊断结果比较。结果 29例患者中符合线路显像真阳性19例，真阴性6例，假阳性、假阴性各2例，其诊断食管癌术后复发转移的灵敏度、特异性和准确性分别为90．5％（19／21例）、75．0％（6／8例）和86．2％（25／29例）；而CT诊断的灵敏度、特异性和准确性分别为71．4％（15／21例）、87．5％（7／8例）和75．9％（22／29例）。在符合线路显像与CT检查均阳性的13例患者中，CT检出病灶20个；而符合线路显像检出27个，比CT多检出的病灶包括食管癌复发，锁骨上、纵隔和肺门淋巴结及骨转移。结论 ^18F-FDG符合线路显像对食管癌术后复发转移的诊断具有较高的临床价值，尤其在临床疑有复发转移而常规影像学检查阴性时有重要意义。     

18-FDG PET/CT在肝癌治疗后AFP升高患者中的应用

目的 探讨18F-脱氧葡萄糖(FDG)PET/CT检测肝癌治疗后甲胎蛋白(AFP)升高患者肿瘤复发和(或)转移病灶的价值.方法 原发性肝细胞癌治疗后血清AFP升高患者123例,皆行全身18F-FDG PET/CT显像.所有图像经图像融合后,进行PET/CT融合图像、PET图像和CT图像帧对帧对比分析.肿瘤复发和(或)转移病灶根据病理检查结果、多种影像学诊断及临床随访而确诊.随访时间均>6个月.采用SPSS 11.5软件进行统计学处理,进行X2检验.结果 123例患者中,明确诊断肿瘤复发和(或)转移者111例.18F-FDG PET显像诊断肿瘤复发和(或)转移78例,其灵敏度为70.3%(78/111);18F.FDG PET/CT显像诊断肿瘤复发和(或)转移97例,灵敏度提高至87.4%(97/111,χ2=9.744,P=0.002).18F.FDG PET/CT诊断肝癌复发和转移的特异性、准确性、阳性预测值和阴性预测值分别为83.3%(10/12)、87.0%(107/123)、98.0%(97/99)和41.7%(10/24).9例高分化肝细胞癌患者均确诊为肿瘤复发和(或)转移,18F-FDG PET/CT显像诊断其肿瘤复发和(或)转移5例,灵敏度(5/9)明显低于总体灵敏度(87.4%;χ2=6.616,P=0.01).结论 18F-FDG PET/CT显像在检测原发性肝癌治疗后AFP升高患者肿瘤复发和(或)转移病灶中有较好的应用价值,但高分化肝细胞癌可能出现假阴性.     

^18F-FDG PET／CT在鼻咽癌临床分期和疗效监测中的应用

目的探讨^18F-FDGPET／CT显像在鼻咽癌首次分期、再分期及疗效监测中的临床应用价值。方法通过分析86例鼻咽癌患者^18F-FDGPET／CT扫描结果,结合其他临床资料和随访结果,计算^18F-FDGPET／CT显像的准确性、特异性、灵敏度、阳性预测值与阴性预测值,并与CT、MRI进行比较。结果^18F-FDGPET／CT与CT、MRI诊断鼻咽癌的准确率、敏感性、特异性、阳性预测值与阴性预测值的差异均有统计学意义（P〈0．05）。依据^18F-FDGPET／CT结果,改变了4例首次分期、14例再分期的临床诊断和22例患者的治疗方案。结论与CT、MRI相比,^18F-FDGPET／CT显像对鼻咽癌的临床分期及疗效监测具有更重要价值。     

F-18 fluorodeoxyglucose positron-emission tomography in the diagnosis of tumor recurrence and metastases in the follow-up of patients with breast carcinoma: a comparison to conventional imaging

AIM: To evaluate the role of F-18-fluorodeoxyglucose positron-emission tomography (F-18 FDG PET) in the follow-up of breast carcinoma in case of clinical suspicion of local recurrence or distant metastases and/or tumor marker increase in correlation to conventional imaging. MATERIAL AND METHODS: Retrospective analysis of the results of F-18 FDG PET (ECAT ART(R), Siemens CTI MS) of 62 patients (age 58.5 +/- 12.8) with surgically resected breast carcinoma (time interval after surgery, 86 +/- 82 months, mean follow-up 24 +/- 12.6 months). Patient- and lesion-based comparison with conventional imaging (CI) including mammography (MG), ultrasonography (US), computerized tomography (CT), magnetic resonance imaging (MRI), radiography (XR) and bone scintigraphy (BS). Furthermore, we evaluated the influence on tumor stage and therapeutic strategy. A visual qualitative evaluation of lesions was performed. RESULTS: On a patient base, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy for detecting local recurrence or distant metastases were calculated to be 97%, 82%, 87%, 96% and 90% compared with 84%, 60%, 73%, 75% and 74% with CI. On a lesion base, significantly more lymph node (84 vs. 23, P < 0.05) and fewer bone metastases (61 vs. 97, P < 0.05) could be detected by using F-18 FDG PET compared with CI. Sclerotic bone lesions were predominantly detected by BS. On the other hand, there were several patients with more FDG positive bone lesions and also mixed FDG positive/Tc-99m methylenediphosphonate (MDP) negative and FDG negative/Tc-99m MDP positive metastases. In case of normal tumor markers, sensitivity, specificity, PPV, NPV and accuracy for detecting local recurrence or distant metastases were calculated to be 100%, 85.0%, 78.6%, 100% and 90.3% for FDG PET and 80%, 50%, 50%, 80% and 61.5% for CI. An upstaging could be observed in 9.7% (6/62) and downstaging in 12.9% (8/62), leading to a change in therapeutic regimen in 13 patients (21%). CONCLUSIONS: F-18 FDG PET demonstrates apparent advantages in the diagnosis of metastases in patients with breast carcinoma, compared with conventional imaging on a patient base. On a lesion base, significantly more lymph node and less bone metastases can be detected by using F-18 FDG PET compared with conventional imaging, including bone scintigraphy. In patients with clinical suspicion but negative tumor marker profile, too, F-18 FDG PET seems to be a reliable imaging tool for detection of tumor recurrence or metastases. Considering the high predictive value of F-18 FDG PET, tumor stage and therapeutic strategy will be reconsidered in several patients.     

Value of 2-[18F]-fluoro-2-deoxy-D-glucose imaging with dual-head gamma camera in coincidence mode: comparison with computed tomography/magnetic resonance imaging in patients with suspected recurrent head and neck cancers

OBJECTIVE: The aim of the present study was to assess the value of dual-head gamma-camera (DHGC) imaging in the coincidence mode using 2-[18F]-fluoro-2-deoxy-D-glucose in differentiating recurrent tumor from posttreatment changes in previously treated head and neck cancer. METHODS: This was a single-center prospective study performed with the approval of our Institutional Review Board. Twenty-nine patients with suspected recurrent head and neck cancers were prospectively enrolled in this study. Dual-head gamma-camera imaging in the coincidence mode followed computed tomography (CT; n = 24)/magnetic resonance imaging (MRI; n = 5) within a period of 1 week (mean = 3.5 days) in all patients. Thirteen patients had definite pathologic confirmation of recurrence by undergoing a biopsy. Sixteen patients, however, did not have a definite pathologic confirmation and were followed clinically. The mean duration of follow-up for the subgroup of patients who were followed clinically was 22.8 months (range: 4-48 months). Sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) for CT/MRI and DHGC imaging in the coincidence mode were calculated. RESULTS: The sensitivity, specificity, PPV, NPV, and accuracy of CT/MRI in the detection of recurrent cancer were 76.5%, 58.3%, 72.2%, 63.6%, and 69%, respectively. In contrast, the sensitivity (100%), NPV (100%), and accuracy (82.8%) of DHGC imaging in the coincidence mode were superior to that of CT/MRI. Dual-head gamma-camera imaging in the coincidence mode had a specificity (58.3%) and PPV (77.3%) comparable to those of CT/MRI. CONCLUSION: Our data suggest that modified positron emission tomography with DHGC imaging in the coincidence mode is a useful tool in the assessment of recurrent head and neck cancer.     

自体干细胞移植前后18F-FDG符合线路显像对非霍奇金淋巴瘤预后的评估价值

目的 探讨非霍奇金淋巴瘤(NHL)患者在自体干细胞移植(ASCT)前后行18F-脱氧葡萄糖(FDG)符合线路显像对于预测患者无进展生存期(PFS)的价值,并将结果 与CT检查进行对比分析.方法 29例经病理检查证实的NHL患者在ASCT前后均进行18F-FDG符合线路显像与CT检查,ASCT后随访时间均>1年.分别计算18F-FDG符合线路显像与CT检查的阳性预测值(PPV)、阴性预测值(NPV)和准确性,采用X2检验比较两者的结果 ,并采用Kaplan-Meier生存分析法行PFS分析.结果 ASCT前,18F-FDG显像的PPV、NPV和准确性分别为85.7%(12/14)、73.3%(11/15)和79.3%(23/29),高于CT检查的55.6%(10/18),45.5%(5/11)和51.7%(15/29);而在ASCT后,18F-FDG显像的PPV、NPV和准确性分别为92.3%(12/13)、75.0%(12/16)和82.8%(24/29),也分别高于CT检查的62.5%(10/16),53.8%(7/13)和58.6%(17/29);18?F-FDG显像和CT两者评价准确性差异有统计学意义(X2值分别为4.884和4.077,P均<0.05).ASCT前后18F-FDG显像阴性与阳性病例的PFS差异也有统计学意义(X2值分别为15.839和20.219,P均<0.005),而同期CT检查的阴性与阳性病例PFS差异无统计学意义(X2=2.468,P=0.116).ASCT前后,18F-FDG显像阴性和阳性患者的1年无进展生存率分别为86.7%(13/15)、87.5%(14/16)和28.6%(4/14)、23.1%(3/13).结论 ASCT前后18F-FDG符合线路显像均具有预测NHL预后的价值,且均优于CT检查.     

F-18 FDG PET/CT evaluation of osseous and soft tissue sarcomas

INTRODUCTION: Osseous and soft tissue sarcomas (OSTS) represent a histologic heterogeneous group of malignant tumors. Most of the current clinical data on the role of F-18 FDG PET in sarcomas come from patients studied with dedicated PET and less frequently with hardware fusion PET/CT. Therefore, we were prompted to review our experience with F-18 FDG PET/CT in OSTS. METHODS: This is a retrospective study (January 2003-December 2005) of 44 patients with histologic diagnoses of OSTS who had F-18 FDG PET/CT at our institution. The group included 22 men and 22 women with an age range of 2 of 84 years (average, 37 +/- 20.2 years). The administered doses of F-18 FDG range 4.1 to 19.5 mCi (average, 14.3 +/- 3 mCi). Reinterpretation of the imaging studies for accuracy and data analysis from medical records was performed. RESULTS: The sensitivity and specificity of combined F-18 FDG PET/CT were 100% (95% confidence interval [CI] = 75.7-100) and 93.3% (95% CI = 78.7-98.1) for the primary OSTS, and 80% (95% CI = 58.4-91.9) and 86.4% (95% CI = 66.7-95.2) for metastases. When interpreted separately, CT outperformed PET for pulmonary metastases detection: CT was 76.5% sensitive and 88% specific, whereas PET was only 57.1% sensitive but 96.4% specific. For detection of other metastases, CT was 82.3% sensitive and 76% specific, with PET demonstrating 78.6% sensitivity and 92.8% specificity. CONCLUSION: Relatively similar results (except better specificity for PET and PET/CT) were noted when examining the rate of metastases detection, excluding pulmonary lesions. However, CT had a better detection rate for pulmonary metastases when compared with PET alone. A negative PET scan in the presence of suspicious CT findings in the chest cannot reliably exclude pulmonary metastases from OSTS.     

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.     

Diagnostic values of F-18 FDG PET or PET/CT,CT, and US for Preoperative Lymph Node Staging in Thyroid Cancer: A Network Meta-Analysis

ObjectiveThis study compared the diagnostic performance of three different imaging modalities for preoperative lymph node (LN) staging in thyroid cancer patients, using a network meta-analysis (NMA).MethodsPubMed and Embase were searched to identify studies evaluating the performance of F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET or PET/CT), computed tomography (CT), and ultrasonography (US) for preoperative LN staging in thyroid cancer patients. The NMA included both patient- and lesion-based analyses. The surface under the cumulative ranking curve (SUCRA) values was used to decide on the most effective diagnostic method.ResultsA total of 3,571 patients from 19 direct comparison studies using three different imaging modalities for preoperative LN staging in thyroid cancer patients were included. US showed the highest SUCRA values for positive predictive values (PPV), negative predictive values (NPV), and accuracy in detection of all cervical LN metastasis. F-18 FDG PET or PET/CT and US showed the highest SUCRA values for PPV and sensitivity, respectively, for central LN, and the highest SUCRA value of specificity and sensitivity, respectively, for lateral LN.ConclusionThe results from this NMA indicate that F-18 FDG PET or PET/CT, CT, and US have complementary diagnostic roles for preoperative staging in thyroid cancer patients.Advances in knowledgeUsing NMA, we comprehensively compared the different diagnostic values and limitations of F-18 FDG PET or PET/CT, CT, and US for the preoperative LN staging in thyroid cancer patients.     

Improving liver lesion characterisation using retrospective fusion of FDG PET/CT and MRI

AimTo compare retrospectively fused FDG PET/CT and MRI (PET/MRI) to FDG PET/CT and MRI for characterisation of indeterminate focal liver lesions as malignant or benign in patients with a known primary malignancy.Materials and methodA retrospective review of 70 patients (30 females, 40 males; mean age 56 ± 14 years) with 150 indeterminate lesions after FDG PET/CT and MRI (mean scan time interval 21 ± 11 days). HERMES® software was used to fuse PET/CT and MRI scans which were reviewed by 2 readers using the Likert score (scale 1–5) to characterise lesions as benign (1–3) or malignant (4–5). Final diagnosis was determined by histopathology or follow up imaging. Results for fused PET/MRI were compared to PET/CT and MRI alone.ResultsFor detection, MRI and fused PET/MRI detected all the lesions while PET/CT detected 89.4%. Characterisation of liver lesions as malignant on PET/CT alone yielded sensitivity, specificity, accuracy, PPV and NPV of 55.6%, 83.3%, 66.7%, 83.3%, 55.6% respectively and 67.6%, 92.1%, 80%, 89.3%, 74.5% for MRI, respectively. The sensitivity, specificity, accuracy, PPV and NPV for characterising lesions as malignant increased to 91.9%, 97.4%, 94.7%, 97.1%, 92.5% with PET/MRI fusion. The sensitivity, specificity, accuracy, PPV and NPV of fused PET/MRI for characterising lesions as malignant remained superior to PET/CT and MRI.ConclusionRetrospective fusion of PET with MRI has improved characterisation of indeterminate focal liver lesions compared to MRI or FDG PET/CT alone.     

The diagnostic role of radionuclide imaging in evaluation of patients with nonhypersecreting adrenal masses.

The aim of this study was to evaluate the role of radionuclide imaging in the characterization of nonhypersecreting adrenal masses. METHODS: A total of 54 patients (19 men, 35 women; mean age, 50 +/- 16 y) with nonhypersecreting unilateral adrenal tumors that had been originally detected on CT or MRI underwent adrenal scintigraphy using different radiotracers. None of the patients showed specific symptoms of adrenal hypersecretion. Screening tests for excess cortical and medullary products showed normal adrenal hormone levels. Radionuclide studies (n = 73) included (131)I-norcholesterol (n = 24), (131)I-metaiodobenzylguanidine (MIBG) (n = 23), and (18)F-FDG PET (n = 26) scans. RESULTS: Histology after surgery (n = 31) or adrenal biopsy (n = 23) was obtained. Adrenal lesions were represented by 19 adenomas, 4 cysts, 1 myelolipoma, 1 neurinoma, 2 ganglioneuromas, 5 pheochromocytomas, 4 pseudotumors, 6 carcinomas, 2 sarcomas, and 10 metastases (size range, 1.5- to 5-cm diameter; mean, 4.9 +/- 3.1 cm). For norcholesterol imaging, diagnostic sensitivity, specificity, and accuracy were 100%, 71%, and 92%, respectively; the positive predictive value (PPV) of the norcholesterol scan to characterize an adrenal mass as an adenoma was 89%, whereas the corresponding negative predictive value (NPV) to rule out this type of tumor was 100%. For MIBG imaging, diagnostic sensitivity, specificity, and accuracy were 100%, 94%, and 96%, respectively; the PPV of the MIBG scan to characterize an adrenal mass as a medullary chromaffin tissue tumor was 83%, whereas the corresponding NPV to rule out this type of tumor was 100%. For FDG PET, diagnostic sensitivity, specificity, and accuracy were 100%, 100%, and 100%, respectively; the PPV of FDG PET to characterize an adrenal mass as a malignant tumor was 100%, whereas the corresponding NPV to rule it out was 100%. Furthermore, in 7 patients with malignant adrenal tumors, FDG whole-body scanning revealed extra-adrenal tumor sites (n = 29), allowing an accurate diagnosis of the disease's stage using a single-imaging technique. CONCLUSION: In patients with nonhypersecreting adrenal masses, radionuclide adrenal imaging, using specific radiopharmaceuticals such as norcholesterol, MIBG, and FDG, may provide significant functional information for tissue characterization. Norcholesterol and MIBG scans are able to detect benign tumors such as adenoma and pheochromocytoma, respectively. Conversely, FDG PET allows for recognition of malignant adrenal lesions. Therefore, adrenal scintigraphy is recommended for tumor diagnosis and, hence, for appropriate treatment planning, particularly when CT or MRI findings are inconclusive for lesion characterization.