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.     

Metastases from non-small cell lung cancer: mediastinal staging in the 1990s--meta-analytic comparison of PET and CT.

PURPOSE: To meta-analytically compare 2-[fluorine 18]fluoro-2-deoxy-D-glucose positron emission tomography (PET) and computed tomography (CT) for the demonstration of mediastinal nodal metastases in patients with non-small cell lung cancer. MATERIALS AND METHODS: English-language reports on the diagnostic performance of PET (14 studies, 514 patients) and/or CT (29 studies, 2,226 patients) for demonstration of mediastinal nodal metastases from NSCLC were selected by using the MEDLINE database. In eligible studies, an objective diagnostic standard was used, data were presented to allow recalculation of contingency tables, and established diagnostic criteria were used for abnormal test results. Summary receiver operating characteristic (ROC) curves were calculated. RESULTS: Pooled point estimates of diagnostic performance and summary ROC curves indicated that PET was significantly more accurate than CT for demonstration of nodal metastases (P < .001). Mean sensitivity and specificity (+/- 95% CI) were 0.79 +/- 0.03 and 0.91 +/- 0.02, respectively, for PET and 0.60 +/- 0.02 and 0.77 +/- 0.02, respectively, for CT. The log odds ratios were 1.79 (95% CI: 1.49, 2.09) for CT and 3.77 (95% CI: 2.77, 4.77) for PET (P < .001). Subgroup analyses did not alter findings. CONCLUSION: PET is superior to CT for mediastinal staging of non-small cell lung cancer, independent of performance index or clinical context of PET imaging.     

Detection of liver metastases from pancreatic cancer using FDG PET.

We evaluated the potential of the glucose analog [18F]fluorodeoxyglucose (FDG) as a PET tracer for the hepatic staging in 168 patients designated for resective pancreatic surgery. METHODS: Metastatic liver disease was confirmed or excluded during surgery or with CT follow-up for at least 6 mo. Proven metastases were then retrospectively identified on preoperative CT (gold standard). Hepatic PET scans of all patients were interpreted blindly. Any focal FDG uptake was considered malignant. Both proven hepatic metastases and suspicious hepatic PET lesions were then compared, lesion by lesion, with CT. Standardized uptake values (SUV) and tumor-to-liver ratios (T/L) were determined for the most intense lesion of each patient. RESULTS: Sensitivity of FDG PET was 68% (15 of 22 patients). The lesion detection rate was 97% (28 of 29 metastases) for lesions >1 cm and 43% (16 of 37 metastases) for lesions < or = 1 cm. Specificity was 95% (138 of 146 patients). Six of eight patients with false-positive results had marked intrahepatic cholestasis (versus 3 of 15 patients with true-positive lesions), one had an infrahepatic abscess and one had a right basal pulmonary metastasis. The SUV and T/L were 4.6+/-1.4 and 2.3+/-1.1, respectively, for malignant lesions and 4.1+/-1.5 and 1.9+/-0.3, respectively, for false-positive lesions and therefore are of limited value. CONCLUSION: FDG PET provides reliable hepatic staging for lesions >1 cm. False-positive results are associated with the presence of marked intrahepatic cholestasis. For lesions < or = 1 cm, FDG PET can define malignancy in 43% of suspicious CT lesions in the absence of dilated bile ducts.     

Impact of FDG PET for staging of Ewing sarcomas and primitive neuroectodermal tumours

AIM: High-grade Ewing sarcomas and Primitive neuroectodermal tumours (PNET) make up the tumours of the Ewing family. Our purpose was to evaluate the value of [18F]fluorodeoxyglucose positron emission tomography (FDG PET) in patients with Ewing tumours. PATIENTS AND METHODS: Twenty-four patients who had PET because of a suspected Ewing tumour during a 5-year period were included in this retrospective study. The images of 33 whole-body FDG PET investigations performed in primary or secondary diagnostics were analysed visually and semi-quantitatively by using standardized uptake values (SUVs). In 14 cases, PET was compared to bone scintigraphy regarding bone lesions. The final diagnosis was based on histology, imaging and follow-up. RESULTS: Histologically, the primary lesions were 10 Ewing sarcoma, 13 PNET and one osteomyelitis. The sensitivity and specificity of an examination-based analysis (presence of Ewing tumour and/or its metastases) were 96 and 78%, respectively. Altogether, 163 focal lesions were evaluated. Sensitivity and specificity regarding individual lesions were 73 and 78%. This lower sensitivity is mainly due to small lesions. In true-positive cases, the mean SUV was 4.54+/-2.79, and the SUVs in two false-positive cases were 4.66 and 1.60. True-positive and false-positive cases could not be differentiated definitively based on SUVs because of overlap and low values in true-positive lesions. In four cases, PET depicted 70 while bone scintigraphy depicted only eight bone metastases. CONCLUSION: An FDG PET investigation is a valuable method in the case of Ewing tumours. PET is superior to bone scintigraphy in the detection of bone metastases of Ewing tumours. For the depiction of small lesions, mainly represented by pulmonary metastases, PET is less sensitive than helical computed tomography. Determination of the role of whole-body FDG PET in diagnostic algorithm needs further investigation.     

Detection of hepatic metastases from cancers of the gastrointestinal tract by using noninvasive imaging methods (US,CT, MR imaging,PET): a meta-analysis

PURPOSE: To perform a meta-analysis to compare current noninvasive imaging methods (ultrasonography [US], computed tomography [CT], magnetic resonance [MR] imaging, and (18)F fluorodeoxyglucose [FDG] positron emission tomography [PET]) in the detection of hepatic metastases from colorectal, gastric, and esophageal cancers. MATERIALS AND METHODS: A MEDLINE literature search and review of article bibliographies and our institutional charts of patients with colorectal cancer identified data with histopathologic correlation or at least 6 months of patient follow-up. Two authors independently abstracted data sets and excluded data without contingency tables or data published more than once. Summary-weighted estimates of sensitivity were obtained and stratified according to specificity of less than 85% or 85% and higher. A covariate analysis was used to evaluate the influence of patient- or study-related factors on sensitivity. RESULTS: Among 111 data sets, nine US (509 patients), 25 CT (1,747 patients), 11 MR imaging (401 patients), and nine PET (423 patients) data sets met the inclusion criteria. In studies with a specificity higher than 85%, the mean weighted sensitivity was 55% (95% CI: 41, 68) for US, 72% (95% CI: 63, 80) for CT, 76% (95% CI: 57, 91) for MR imaging, and 90% (95% CI: 80, 97) for FDG PET. Results of pairwise comparison between imaging modalities demonstrated a greater sensitivity of FDG PET than US (P =.001), CT (P =.017), and MR imaging (P =.055). CONCLUSION: At equivalent specificity, FDG PET is the most sensitive noninvasive imaging modality for the diagnosis of hepatic metastases from colorectal, gastric, and esophageal cancers.     

FDG PET is superior to CT in the prediction of viable tumour in post-chemotherapy seminoma residuals

AIM: In advanced seminoma the management of residuals after completion of chemotherapy is controversial. Some centres routinely perform surgery for lesions > or =3 cm diameter, others recommend surgery solely if the residual fail to shrink or show even growth. This study prospectively investigates whether FDG PET can improve the prediction of viable tumour in post-chemotherapy seminoma residuals. MATERIALS AND METHODS: After an expansion of a previous study population, 54 patients from eight centres with metastatic seminoma and a CT-documented mass after chemotherapy were included in the study. Six patients were excluded from evaluation because of protocol violations. After PET, the patients underwent either surgery or were followed clinically. On follow-up the lesions were considered to be non-viable when there was unequivocal shrinking, or when the lesion remained morphologically stable for at least 24 months. Any lesion growth was assumed to be malignant. PET results were compared to CT discrimination (< or > or =3 cm) of the residual masses. RESULTS: Fifty-two PET scans were evaluable. After adequate chemotherapy, there were 74 CT-documented residual masses ranging in size from 1 to 11 cm (median, 2.2 cm). Their dignities were confirmed histologically in 13 lesions, or by follow-up CT in 61 lesions. Four of forty-seven lesions <3 cm and 11/27 lesions > or =3 cm were viable. PET was true positive in one lesion <3 cm and in 11 lesions > or =3 cm, false negative in three lesions <3 cm, and true negative in 59 lesions (43 lesions <3 cm). No PET scan was false positive. In detecting viability the sensitivity and specificity was 73% (95% CI, 44-88), and 73% (59-83), respectively, for CT (< or > or =3 cm); and 80% (51-95), and 100% (93-100), respectively, for PET (specificity, P < 0.001). CONCLUSION: In post-chemotherapy seminoma residuals, a positive PET is highly predictive for the presence of viable tumour. The specificity of PET is significantly higher than that of CT when using a > or =3 cm cut-off. A negative PET scan is excellent for the exclusion of disease in lesions > or =3 cm, with a somewhat higher sensitivity than CT (n.s.). PET can contribute to the management of residual seminoma lesions, especially in terms of avoiding unnecessary additional treatment for patients with lesions > or =3 cm.     

Diagnostic evaluation of separately acquired PET and CT images by nuclear medicine physicians and radiologists in cancer patients

The aim of our study was to analyze how many oncology patients might benefit from a) integrated positron emission tomography - multidetector computed tomography (PET/MDCT) and additionally b) clinically relevant information provided by either the CT scan or PET scan. A total of 285 consecutive patients 164 male and 121 female, age range 17-84 years, 153 lung cancer, 112 lymphoma, 20 miscellaneous, referred for PET and separate CT scan, were included. The CT scan was performed after the intravenous injection of a soluble contrast media. Patients were retrospectively classified into six Groups: Group I: No pathological uptake on the PET scan, Group II: Suspected lesions were correctly identified by the PET scan alone, Group III: Side-by-side evaluation of PET and CT appeared sufficient to assess the localization of lesions, Group IV: Side-by-side reading was not sufficient and integrated PET/CT was considered beneficial. Additionally all patients with a CT scan with additional clinical relevant information (not visualized by the PET scan) were classified in Group V. Group VI was set for lesions detected by PET alone (not visualized by the CT scan). The CT scan was used as the gold standard to confirm or disprove PET lesion localization. Our results showed: A number of 77 patients, (Group I: 77/285, 27%) had no pathologic fluorine-18-fluorodeoxyglucose (18F-FDG)-uptake. Lesions were correctly localized by either conventional PET alone (Group II: 76/285, 27%) or side-by-side evaluation of PET and CT scans (Group III: 44/285, 15%). Integrated PET/CT or software fusion, was considered beneficial in 31% (88/285) of the patients with pathological 18F-FDG-uptake (Group IV). Additionally to the above, in 15% of all patients clinically relevant information, referring to disseminated small pulmonary lesions, abdominal aortic aneurysms >5 cm, thrombi or pulmonary emboli, was also provided by the CT scan (Group V). Also, in 7% of all patients, unsuspected pathological lesions, mainly bone metastases, were correctly detected by PET alone (Group VI). In conclusion, in 54% of all oncologic patients, PET alone was diagnostic. In 46% of all patients side-by-side reading (15%) or integrated PET/CT images (31%) were considered beneficial for more accurate anatomical localization of the lesions. Additionally, the CT scan added clinically relevant information in 15% of all patients and the PET scan showed unsuspected metastases in 7% of all studied patients. Therefore, integrated reading of PET and MDCT images by nuclear physicians and radiologists may gain quality in the staging of oncology patients.     

Clinical value of FDG PET or PET/CT in urinary bladder cancer: a systemic review and meta-analysis

Aim

The purpose of the current study was to conduct a systemic review and meta-analysis of the published literature to evaluate the diagnostic accuracy of FDG PET or PET/CT in urinary bladder cancer.

Materials and methods

The authors conducted a systematic MEDLINE search of articles published between January 2000 and December 2010. Two reviewers independently assessed the methodological quality of each study. We conducted a meta-analysis of pooled sensitivity and specificity in detecting primary and metastatic lesions of bladder cancer.

Results

Six studies met the inclusion criteria. The pooled sensitivity and specificity of PET/CT for primary lesion detection of bladder cancer were 0.90 (95% CI: 0.70–0.99) and 1.00 (95% CI: 0.74–1.00), respectively. The pooled sensitivity and specificity of FDG PET or PET/CT for staging or restaging (metastatic lesions) of bladder cancer were 0.82 (95% CI: 0.72–0.89) and 0.89 (95% CI: 0.81–0.95), respectively.

Conclusion

The diagnostic accuracy of FDG PET or PET/CT is good in metastatic lesions of urinary bladder cancer. Due to the small number of patients and limited number of studies analyzed, the diagnostic capability of FDG PET or PET/CT in detection of primary bladder wall lesions could not be assessed.     

High-risk melanoma: accuracy of FDG PET/CT with added CT morphologic information for detection of metastases

PURPOSE: To prospectively determine the accuracy of positron emission tomography (PET)/computed tomography (CT) with added CT morphologic information for depiction of metastases in patients with high-risk melanoma and negative findings for metastases at PET, by using histologic findings or additional imaging and/or follow-up findings as reference standard. MATERIALS AND METHODS: Institutional review board approval was obtained. Informed consent was obtained from patients. One hundred twenty-four consecutive high-risk melanoma patients (65 female, 59 male; mean age, 54.4 years; range, 15-82 years) were included. Fluorine 18 fluorodeoxyglucose (FDG) PET/CT was performed. First, PET/CT scans were evaluated for presence of metastases with increased FDG uptake; CT anatomic location was determined. Lesions were considered metastases if there was focal uptake higher than that of background tissue. Second, coregistered CT images of combined PET/CT scans were evaluated for presence of lesions without FDG uptake. Findings were compared with reference standard findings to determine the accuracy of each evaluation. McNemar test was used to assess statistical differences in accuracy. RESULTS: In 53 of 124 patients, metastases were found. In 46 of 53 patients with metastases, lesions had increased FDG uptake. In seven patients with metastatic disease, metastases did not have increased FDG uptake (maximum standard uptake value [SUV], <1.5; n = 5) or had faint FDG uptake (maximum SUV, 2.5 and 2.9; n = 2)-findings that were inconclusive with PET alone. These lesions were interpreted as metastases only with coregistered CT images. Lesions missed with PET were located in the lungs, iliac lymph nodes, subcutis, and psoas muscle. Sensitivity, specificity, and accuracy, respectively, of PET/CT for depiction of metastases were 85%, 96%, and 91%, and those of PET/CT with dedicated CT interpretation were 98%, 94%, and 96% (P = .016). CONCLUSION: Dedicated analysis of coregistered CT images significantly improves the accuracy of integrated PET/CT for depiction of metastases in patients with high-risk melanoma.     

The clinical value of 18F-FDG PET/CT in the evaluation of bone metastases undetermined origin

PurposeTo evaluate the clinical value of ¹⁸F-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) in detection of primary lesions of bone metastases.MethodsThe PET/CT scans of 77 patients with bone metastases undetermined origin were retrospectively reviewed. The results of clinical information were collected.ResultsForty-four suspected primary tumors were found on the PET/CT images in 77 patients of bone metastases, including 40 patients with the primary tumor confirmed, and 4 patients false-positive. In 37 patients, no primary lesions were detected, including one patient false-negative (signet-ring cell carcinoma). The sensitivity, specificity, and accuracy was 97.6%, 88.9%,and 93.5% respectively. The primary lesions of 51.9% patients could be diagnosed by PET/CT.ConclusionPET/CT is helpful in detecting the primary lesions of bone metastases.     

18F-FDG PET/CT与PET/MRI在结直肠癌肝转移诊断中的比较分析

目的:比较 18F-氟脱氧葡萄糖（FDG） PET/CT与PET/MRI显像对结直肠癌肝转移的诊断价值。 方法:回顾性分析2018年9月至2019年9月于宁波明州医院行全身 18F-FDG PET/CT显像及上腹部 18F-FDG PET/MRI显像,并疑似有结直肠癌肝转移...     

PET/CT与增强CT检测乳腺癌及其腋淋巴结转移的对照研究

目的探讨^18F-脱氧葡萄糖（FDG）PET／CT显像与螺旋CT增强扫描检测乳腺癌及其腋淋巴结转移的临床价值。方法27例乳腺肿块患者于同日行^18F—FDG PET／CT显像与CT增强扫描。患者俯卧于乳腺专用泡沫垫上接受检查，前者图像由3位核医学科医师采用目测法结合半定量法进行诊断，后者图像由3位影像科医师分析诊断；最后与病理检查结果对照。结果27例患者PET／CT与增强CT均发现31个乳腺肿块，病理检查证实其中21个为乳腺癌，10个为良性病变；发现腋淋巴结91个，共有66个转移（1例有双侧腋淋巴结转移）；PET／CT显像检测乳腺癌原发灶的灵敏度为80．95％，特异性为90％，阳性预测值为94．44％；检测淋巴结转移的灵敏度为89．39％，特异性为88％，阳性预测值为95．16％。增强CT检测乳腺癌原发灶的灵敏度为90．48％，特异性为60％，阳性预测值为82．61％；检测淋巴结转移的灵敏度为86．36％，特异性为52％，阳性预测值为82．61％。^18F—FDG PET／CT和增强CT对腋淋巴结状态的诊断与病理检查结果的列联系数分别为0．64和0．37；两者对乳腺癌及其腋淋巴结转移的诊断特异性差异有显著性（P〈0．05）；对直径〈2cm的病灶，^18F—FDG PET／CT诊断准确性明显高于增强CT（P〈0．05）。结论^18F—FDG PET／CT对诊断乳腺癌及其腋淋巴结转移的特异性均高于增强CT。     

Additional value of integrated PET-CT in the detection and characterization of lung metastases: correlation with CT alone and PET alone

The purpose was evaluating retrospectively the additional value of integrated positron emission tomography (PET) and computed tomography (CT) in the detection of pulmonary metastases in comparison with CT and PET alone. Fifty-six lung nodules, divided into three groups according their size, detected in 24 consecutive patients with a known primary tumor were retrospectively evaluated with integrated PET-CT, CT and PET. The nature of these nodules was determined by either histopathology or a follow-up of at least 6 months. The CT and PET images of the integrated PET-CT were evaluated separately by a radiologist and a nuclear medicine physician, the integrated PET-CT images were evaluated by a chest radiologist and nuclear medicine physician in consensus. The investigators were asked to search lung nodules and to determine whether these nodules were metastases or not. Sensitivity and accuracy for CT, PET and integrated PET-CT for characterization of all pulmonary nodules were, respectively: 100%, 90%, 100% and 57%, 55%, 55%. There was no significant difference in the characterization of pulmonary nodules between integrated PET-CT and CT alone (P=1.000) and PET alone (P=0.1306). An accurate evaluation is only possible for lesions larger than 1 cm.     

基于PET/CT、HRCT特征的评分系统鉴别诊断孤立性肺部病变的临床研究

目的 探讨基于PET/CT、HRCT影像学特征的评分系统对孤立性肺部良恶性病变的诊断价值。方法 回顾性分析行PET/CT检查的孤立性占位性肺病变112例,其中良性病变44例,恶性病变68例。对孤立性肺病变的12项PET/CT及HRCT影像特征进行评估,初步建立量化分级系统,采用受试者工作特征（ROC）曲线分析良恶性病变的最佳诊断评分临界值。结果 PET/CT及HRCT预测孤立性肺部病变的指标包括年龄≥60岁（2分）、病灶大小≥1.0 cm（2分）、密度不均匀（2分）、边界清楚（1分）、SUV_max≥2.5（2分）、ΔSUV_max≥1.0（2分）、滞留指数≥15%（2分）、分叶征（3分）、毛刺征（3分）、胸膜牵拉征（3分）、空泡征（3分）。根据各项指标建立评分系统,随着评分增加,恶性率逐渐增高,通过ROC曲线得出12分为区分良、恶性病变的最佳临界点,灵敏度为92.6%,特异度为81.8%。结论 基于PET/CT、HRCT影像学特征的量化分级系统有助于鉴别孤立性肺部良恶性病变。     

Positron-emission tomography and computed tomography of cystic pancreatic masses

AIM: To investigate the sensitivity and specificity of computed tomography (CT), positron-emission tomography (PET), and both methods in combination, for determining whether cystic pancreatic tumours are malignant. MATERIALS AND METHODS: We retrospectively identified all patients with cystic pancreatic tumours who underwent separate PET and contrast-enhanced CT examinations within a 1-month interval. Tumours were classified as benign or malignant on CT (two radiologists, independently), PET [a reported standardized uptake value (SUV) of 2.5 was taken as the cut-off between benign and malignant], and with PET and CT images together (two radiologists, in consensus). Readers were blinded to pathological and other radiological findings. Mean patient age and lesion size were compared between benign and malignant groups using Student's t-test. For CT findings, odds ratios (OR) and confidence intervals (CI) were calculated using multivariate logistic regression models. For CT, PET, and the combined images, sensitivities and specificities were calculated, and compared between groups using Fisher's exact test. RESULTS: Thirty patients were identified. The best CT predictor of malignancy was size; mean diameter was 2.3 cm (benign) and 4.1 cm (malignant) (p<0.01); OR was 2.80 (95% CI, 1.26-6.20). Sensitivities of CT, PET and combined PET/CT images were 67-71, 57, and 86%, respectively. PET/CT was more sensitive than PET (p<0.01) or CT (p<0.01) alone. Specificities of CT, PET, and combined PET/CT images were 87-90, 65, and 91%, respectively. PET/CT was more specific than PET (p<0.01) but not CT (p>0.05). CONCLUSION: The sensitivity and specificity of combined PET and CT images is comparable with or superior to either CT or PET alone in determining malignancy in cystic pancreatic lesions.     

Sensitivity of PET/MR images in liver metastases from colorectal carcinoma

Our aim was to evaluate the sensitivity of positron emission tomography/magnetic resonance image (PET/MRI) in the detection of liver metastases in patients from colorectal cancer as compared with computed tomography (CT), magnetic resonance imaging (MRI), PET and PET/CT images. From April 2008 to April 2010, twenty-four patients (mean age 56.5±10.5 years) with liver metastases from colorectal cancer diagnosed by pathology were retrospectively studied as above. All image data were respectively collected and fused. PET/CT and PET/MRI fusion images were successfully performed with a PET-MR-CT robot transmission-fusion imaging system. Pathologic findings and clinical follows-up were performed as referenced standards. Images were reviewed independently by at least three experts. We found a total number of 121 metastatic lesions and 35 of them, with a maximum diameter less than 1cm. According to a per-lesion analysis, the sensitivity on liver metastases was 64.5%, 80.2% and 54.5% on CT, MRI and PET, respectively. Based on reconstruction imaging analysis, PET/CT and PET/MRI showed sensitivities of 84.2% and 98.3%. Sensitivity comparison of PET/MRI had superior sensitivity of 98.08%. Paired data analysis (McNemar) resulted a type I error which equated to 0.05. There was a statistically significant difference between CT and MRI or PET for the detection of patients with liver metastatic lesions (P<0.05). However, PET/MRI can efficiently detect more metastatic lesions than PET/CT (P<0.05) among those with diameter <1cm. In conclusion, PET/MRI was a quite efficient diagnostic modality compared to conventional imaging modalities and should be considered the procedure of choice in the detection of liver metastatic lesions from colorectal cancer.     

Diagnostic test accuracies of F-18 FDG PET/CT for prediction of microvascular invasion of hepatocellular carcinoma: A meta-analysis

PurposeThe aim of the current meta-analysis was to evaluate diagnostic accuracies of preoperative F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) or positron emission tomography/computed tomography (PET/CT) for prediction of microvascular invasion (MVI) in hepatocellular carcinoma (HCC) patients.MethodsThe scientific database such as PubMed, Cochrane, and Embase database were searched for studies evaluating diagnostic accuracies of preoperative F-18 FDG PET or PET/CT for prediction of MVI in HCC patients up to November 30, 2020.ResultsFourteen eligible studies (1276 patients) were enrolled. The pooled sensitivity for F-18 FDG PET or PET/CT was 0.67 (95% CI; 0.57–0.76) with heterogeneity and a pooled specificity of 0.80 (95% CI; 0.74–0.85) with heterogeneity. Likelihood ratio (LR) syntheses gave an overall positive likelihood ratio (LR+) of 3.3 (95% CI; 2.5–4.5) and negative likelihood ratio (LR−) of 0.41 (95% CI; 0.31–0.55). The pooled diagnostic odds ratio (DOR) was 8 (95% CI; 5–14). Summary receiver operating characteristic (ROC) curve indicates that the area under the curve was 0.81 (95% CI; 0.78–0.84).ConclusionThe current meta-analysis showed a low sensitivity and moderate specificity of F-18 FDG PET or PET/CT for the prediction of MVI in HCC patients. F-18 FDG PET or PET/CT might not be useful for the preoperative prediction of MVI in HCC patients and should not be used to exclude MVI. Therefore, cautious application and interpretation should be paid to the F-18 FDG PET or PET/CT for the prediction of MVI in HCC patients preoperatively.     

Noninvasive assessment of Crohn's disease intestinal lesions with (18)F-FDG PET/CT.

Pilot studies have shown good sensitivity and specificity for (18)F-FDG PET in detecting gastrointestinal lesions of Crohn's disease. The combination of (18)F-FDG PET with CT may further improve the localization and characterization of lesions with increased (18)F-FDG uptake. Our aim was to assess the use of (18)F-FDG PET/CT in evaluating the activity and location of Crohn's disease along the gastrointestinal tract. METHODS: After giving informed consent, 22 patients with Crohn's disease were prospectively studied. They underwent (18)F-FDG PET/CT, followed by ileocolonoscopy within 1 wk (mean, 2 d). The Crohn's disease activity index (CDAI) was calculated, and serum C-reactive protein (CRP) and fecal calprotectin were measured before endoscopy. The Crohn's disease endoscopy index of severity (CDEIS) was calculated during endoscopy. The global CDEIS score and endoscopic subscores for various ileocolonic segments were used for analysis. RESULTS: Globally, 95 intestinal and colonic segments in 22 patients were analyzed. (18)F-FDG PET/CT detected 35 of 48 endoscopically affected segments (sensitivity for the detection of endoscopic lesions, 72.9%). The sensitivity of (18)F-FDG PET/CT for the detection of severe endoscopic lesions (deep ulcers and strictures) was 100% (14/14). The global PET/CT score significantly correlated with CDEIS (r = 0.51; 95% confidence interval [CI], 0.09-0.77; P = 0.017), CDAI (r = 0.58; 95% CI, 0.17-0.80; P = 0.005), and CRP (r = 0.56; 95% CI, 0.19-0.81; P = 0.007). CONCLUSION: (18)F-FDG PET/CT was globally well correlated to the clinical, endoscopic, and biologic activity of Crohn's disease. Above all, this technique had a good sensitivity for the detection of intestinal and colonic segments with moderate to severe mucosal lesions. The potential impact of this promising tool on the global management of patients with Crohn's disease should be further evaluated in prospective studies.     

18F-FDG PET/CT在宫颈癌诊断中的应用

目的 探讨18F-脱氧葡萄糖(FDG) PET/CT在宫颈癌诊断及其复发、转移灶探测中的应用价值.方法 88例患者行腹部或全身18F-FDG PET/CT显像,其中初诊者30例(宫颈良性病变11例,宫颈癌19例),宫颈癌治疗后58例.病灶根据病理检查、多种影像诊断技术及临床随访确诊,随访时间均为6个月～3年.结果 30例初诊者中,PET/CT诊断宫颈癌的灵敏度、特异性和准确性分别为17/19,10/11和27/30(90.0%).58例治疗后患者中,11例存在肿瘤复发或残余,PET/CT诊断肿瘤复发、残余的灵敏度、特异性和准确性分别为10/11,47/47(100.0%)和57/58(98.3%).41例有肿瘤转移,PET/CT诊断转移灶的灵敏度、特异性和准确性分别为92.7%,88.9%和90.9%;转移灶以盆腹腔淋巴结为主,39.0%有盆腔淋巴结转移,27.3%有腹膜后淋巴结转移,所有淋巴结转移患者中PET/CT发现26.8%病灶直径＜1.0cm.28.6%(22/77)的患者PET/CT发现腹腔外远处转移灶.18例输尿管梗阻患者中,16例PET/CT发现为肿瘤侵犯压迫所致.结论 18F-FDG PET/CT显像在宫颈癌的诊断及其复发、转移灶探测中有良好的应用价值,尤其是对远处转移灶和小淋巴结转移灶的检测,可使临床分期更准确.     

18F-FDG PET or PET/CT for detection of metastatic lymph nodes in patients with endometrial cancer: A systematic review and meta-analysis

The present study assessed the diagnostic performances of 18F-FDG PET or PET/CT in detecting pelvic and/or paraaortic lymph node metastasis in patients with endometrial cancer. METHODS: Through a search of MEDLINE (January 1998 to March 2011), an overall weighted average for sensitivity and specificity as well as pooled estimates of positive and negative likelihood ratios were calculated. A summary receiver-operating-characteristics (sROC) curve was constructed and the area under the sROC curve (AUC) was calculated. I-square was calculated to explore heterogeneity. RESULTS: The present study included 243 patients from seven studies. Results indicated a lack of significant heterogeneity for sensitivity and specificity (I(2)<50% and p>0.05). The overall pooled estimates for sensitivity and specificity of FDG-PET or PET/CT scans in the detection of pelvic and/or paraaortic metastasis were 63.0% (95% CI, 48.7-75.7%) and 94.7% (95% CI, 90.4-97.4%), respectively. The positive likelihood ratio was 10.465 (95% CI, 5.646-19.396) and the negative likelihood ratio 0.399 (95% CI, 0.284-0.560). The AUC was 0.9533. The overall diagnostic accuracy (Q* index) was 89.5%. Conclusion The high positive likelihood value confirms the reliability of a positive FDG-PET or PET/CT to detect pelvic and/or paraaortic lymph nodes metastasis in patients with untreated endometrial cancer. FDG-PET or PET/CT may prove beneficial to surgeons when selecting appropriate patients on whom to perform lymphadenectomy.