Diagnostic Performance of DWI With Multiple Parameters for Assessment and Characterization of Pulmonary Lesions: A Meta-Analysis.

OBJECTIVE: The objective of our study was to evaluate the diagnostic performance of DWI using a 5-point rank scale, lesion-to-spinal cord signal intensity ratio, which we refer to as "LSR," and apparent diffusion coefficient (ADC) for the characterization of pulmonary lesions. MATERIALS AND METHODS: After a literature search in several databases, two investigators independently selected studies, assessed methodologic quality, and extracted data. On a per-lesion basis, we pooled and compared the three parameters for malignant and benign lesions. Also, we determined pooled sensitivity and specificity with individual 95% CIs. RESULTS: In total, 31 articles involving 2368 lesions were included. The mean scores of malignant and benign lesions on the 5-point scale were 3.83 (95% CI, 3.71-3.96) and 2.36 (95% CI, 2.18-2.54), respectively. The mean LSRs of malignant and benign lesions were 1.15 (95% CI, 1.07-1.24) and 0.71 (95% CI, 0.62-0.79). The mean ADC values of malignant and benign lesions were 1.23 (95% CI, 1.21-1.24) and 1.72 (95% CI, 1.68-1.77). All three parameters differed significantly between malignant and benign lesions (p < 0.05). On the basis of these parameters, the pooled sensitivity and specificity were 0.88 (95% CI, 0.84-0.91) and 0.75 (95% CI, 0.68-0.80) for the 5-point scale, 0.80 (95% CI, 0.75-0.85) and 0.85 (95% CI, 0.76-0.92) for LSR, and 0.84 (95% CI, 0.82-0.86) and 0.84 (95% CI, 0.81-0.87) for ADC. CONCLUSION: Three DWI parameters-a visual parameter (score on a 5-point scale), semiquantitative parameter (LSR), and quantitative parameter (ADC)-can help to distinguish malignant from benign pulmonary lesions.

Physiological uptake of 18F-FDG in the vertebral bone marrow in healthy adults on PET/CT imaging.

BACKGROUND: 18F-fluorodeoxyglucose *Equal contributors. positron emission tomography/computed tomography (18F-FDG PET/CT) has proven to be a valuable imaging modality for the assessment of bone marrow condition. PURPOSE: To investigate the physiological uptake of 18F-FDG in the vertebral bone marrow in healthy adults on PET/CT imaging, and correlate the appearance with clinical factors including gender, body mass index, and age. MATERIAL AND METHODS: A total of 64 healthy individuals underwent PET/CT scan, and for each vertebral body, the mean and maximum standardized uptake value (SUVmean and SUVmax) were determined in the central slice of vertebral body on the transversal fused PET/CT image. For each individual, the FDG uptake of the four regions was obtained by averaging the SUVmean and SUVmax of the vertebrae in individual regions. RESULTS: The FDG uptake from thoracic to sacral vertebrae showed an upward trend first, then a downward trend, while that of cervical vertebrae was relatively stable. The SUVmax and SUVmean values of bone marrow in the old group (age ≥ 50 years) were significantly lower than those in the young group (age < 50 years) in all regions of the spine ( P < 0.05). FDG uptake of the whole spine showed significant negative correlation with age, and the strongest correlation was observed in lumbar spine (SUVmean: r = -0.364, P < 0.05; SUVmax: r = -0.344, P < 0.05). CONCLUSION: FDG uptake showed a tendency to increase first then decrease from thoracic to sacral vertebrae while the tendency was not obvious in cervical vertebrae. In addition, the glycolytic metabolism of all the four regions decreased with advancing age.

Correlations of 18F-FDG and 18F-FLT uptake on PET with Ki-67 expression in patients with lung cancer: a meta-analysis.

Background Positron emission tomography (PET) imaging using the radiotracers 18F-fluorodeoxyglucose (FDG) or 18F-fluorothymidine (FLT) has been proposed as imaging biomarkers of cell proliferation. Purpose To explore the correlations of FDG and FLT uptake with the Ki-67 labeling index in patients with lung cancer. Material and Methods Major databases were systematically searched for all relevant literature published in English. The correlation coefficient (rho) and its 95% confidence interval (CI) of individual studies were meta-analyzed using a random-effects model. The sources of heterogeneity were explored by subgroup analyses. Results Twenty-seven articles involving 1213 patients were included in this meta-analysis, comprising 22 studies for FDG uptake/Ki-67 expression correlation and eight for FLT uptake/Ki-67 expression correlation. The pooled rho values for 18F-FDG/Ki-67 correlation and 18F-FLT/Ki-67 correlation were 0.45 (95% CI, 0.41-0.50) and 0.65 (95% CI, 0.56-0.73), respectively, which indicated a moderate correlation for the former and a significant one for the latter. Although the subgroup analyses based on study design, scanner, sample method, and Ki-67 labeling method did not significantly explain the heterogeneity, these factors were potential sources of heterogeneity. In lung cancer, the pooled SUVmax of FDG uptake was significantly higher than that of FLT uptake (7.59 versus 3.86, P < 0.05). In addition, compared to FDG, FLT showed higher specificity yet lower sensitivity for the diagnosis of pulmonary lesions. Conclusion Both 18F-FDG and 18F-FLT correlate significantly with the Ki-67 labeling index in pulmonary lesions, and the latter, with a stronger correlation, may be more reliable for assessing tumor cell proliferation in lung cancer.

Is postablation whole-body 131 I scintigraphy still necessary in intermediate-risk papillary thyroid cancer patients with pre-ablation stimulated thyroglobulin <1 ng/mL?

OBJECTIVE: Postablation whole-body scintigraphy, which is performed 5-7 days after administration of ablation activity of radioactive iodine-131 (131 I) in patients with thyroid cancer, is considered a routine procedure for remnant ablation and a useful tool for disease staging. However, the relationship of pre-ablation stimulated thyroglobulin (s-Tg) levels with postablation scintigraphic findings has not been evaluated. The current study was designed to determine the diagnostic value of postablation 131 I scintigraphy during initial staging and risk stratification in intermediate-risk papillary thyroid cancer (PTC) patients with pre-ablation s-Tg < 1 ng/ml at the time of ablation. DESIGN: From January 2013 to July 2015, consecutive PTC patients at intermediate-risk of recurrence according to American Thyroid Association criteria were prospectively recruited. Patients had to have pre-ablation s-Tg < 1 ng/ml in the absence of anti-Tg antibody at the time of ablation. Systematic pre-ablation neck ultrasonography was performed for each patient. Postablation whole-body planar scintigraphy was obtained 5 days after administration of ablation activity of 131 I. Single photon emission computed tomography/low-dose computed tomography was added for patients whose planar findings were inconclusive. RESULTS: Among 756 patients ablated, 240 (31·7%) patients were eligible for the analysis. Pre-ablation neck ultrasonography revealed lymph node metastases in eight of the 240 patients. Postablation scintigraphy showed ectopic neck uptake corresponding to the lymph nodes seen by ultrasonography in four patients and revealed neck lymph node metastases in another two patients whose ultrasonography findings were negative. None of the 240 patients showed distant metastasis on postablation scintigraphy. Neither staging nor initial risk stratification was altered by postablation scintigraphy in the included patients with pre-ablation s-Tg < 1 ng/ml. CONCLUSIONS: As postablation whole-body scintigraphy played a minimal role in improving staging or initial risk stratification in intermediate-risk PTC patients with pre-ablation s-Tg < 1 ng/ml, we propose that postablation scintigraphy may be omitted in this group of patients. Multi-institutional larger studies are necessary to draw definitive conclusions.

Performance of DWI in the Nodal Characterization and Assessment of Lung Cancer: A Meta-Analysis.

OBJECTIVE: The purpose of this study is to assess the diagnostic performance of DWI in the N stage assessment of patients with lung cancer. MATERIALS AND METHODS: The PubMed, EMBASE, Cochrane Library, Web of Science, and EBSCO English-language databases and two Chinese-language databases were searched for eligible studies. On the basis of the data extracted from included studies, we determined the pooled sensitivity and specificity, calculated the positive and negative likelihood ratios, and constructed summary ROC curves. In addition, we also performed threshold effect analysis, metaregression analysis, subgroup analysis, and publication bias analysis to explain the source of heterogeneity. RESULTS: A total of 18 articles involving 1116 patients met the inclusion criteria. On a per-patient basis, the pooled sensitivity and specificity estimates of DWI were 0.68 (95% CI, 0.63-0.73) and 0.92 (95% CI, 0.90-0.94), respectively. On a per-lesion basis, the corresponding estimates were 0.72 (95% CI, 0.69-0.75) for sensitivity and 0.96 (95% CI, 0.95-0.96) for specificity. Only the analysis method (quantitative vs qualitative) affected the diagnostic accuracy on the basis of subgroup and metaregression analysis. CONCLUSION: Current evidence suggests that DWI is beneficial in the nodal assessment of patients with lung cancer, and it is necessary to conduct high-quality prospective studies regarding the use of DWI in detecting metastatic lymph nodes of lung cancer to determine its true value.

Thyroid cancer: radiation safety precautions in 131I therapy based on actual biokinetic measurements.

PURPOSE: To formulate radiation precautions for patients with thyroid cancer who are undergoing thyroid hormone withdrawal-induced hypothyroidism and iodine 131 ((131)I) therapy through actual biokinetic measurements. MATERIALS AND METHODS: Informed consent and institutional review board approval were obtained. From October 2008 to December 2011, consecutive patients with differentiated thyroid cancer who had been prepared for (131)I ablation treatment or (131)I treatment for metastatic disease during follow-up were prospectively recruited. Calculations based on deduced whole-body retention and measured iodine biokinetics in thyroidal tissue were derived to determine the thyroidal and extrathyroidal compartment uptake fractions and effective half-lives. Precaution times necessary to avoid close contact with family members and the general public were derived from these parameters and regulatory dose limits. RESULTS: Seventy-seven patients (36 with ablation treatments, 41 with follow-up treatments) were eligible for the analysis. Actual dose rates from patients after therapeutic (131)I administration were greatly lower than those described in the American Thyroid Association (ATA) and Nuclear Regulatory Commission (NRC) models: The mean initial dose rate at 0.3 m for patients with ablation treatment was only 28% (0.183/0.655 µSv/h/MBq) ± 2.9 (standard deviation) (range, 12.1%-38.3%) and 36% (0.183/0.511 µSv/h/MBq) ± 3.7 (range, 15.5%-49.1%) of that described in the NRC and ATA models, respectively; the equivalent values for patients with follow-up treatment were only 30% (0.195/0.655 µSv/h/MBq) ± 3.5 (range, 12.5%-45.3%) and 38% (0.195/0.511 µSv/h/MBq) ± 4.5 (range, 16.0%-58.1%), respectively. The actual mean effective (131)I half-life in the thyroid remnant tissue was greatly lower than that described in the ATA and NRC models: 47.6 versus 175.2 hours. CONCLUSION: On the basis of the current dose limits, typically administered activities of 3.7 GBq to a patient with ablation treatment or 7.4 GBq to a patient with follow-up treatment required 3 days of sleeping apart for keeping the doses to pregnant women and children below 1 mSv. No precautions were required for non-cosleeping nonpregnant adult family members.

[The diagnostic value of 99mTc-MDP bone scan and computed tomography for bone metastases of breast cancer: a systematic review].

According to the inclusion and exclusion criteria, we searched for relevant original articles in some big Chinese and English databases. The qualities of the studies were evaluated with QUADAS quality assessment tool. A software program, Meta-disc, was used to obtain the pooled estimates and heterogeneity test for sensitivity, specificity, SROC curve, and so on. Finally the 17 article were included. On a per-patient basis, the pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (LR+), negative likelihood ratio (LR-), diagnostic odds ratio (DOR), Q*, SROC area under curve for 99mTc-MDP bone scan and computed tomography (CT) were 0. 87 and 0.99, 0.81 and 0.98, 3.88 and 13.86, 0.2 and 0.03, 27.73 and 612.17, 0.8418 and 0.9732, 0.9097 and 0.9952, respectively. On a per-focus basis, the pooled SEN, SPE, LR+, LR-, DOR, Q*, SROC area under curve for 99mTc-MDP bone scan was 0.86, 0.97, 13.32, 0.16, 102.4, 0.8944, 0.9528, respectively. For CT, only 1 article were included. This paper demonstrate: whether 99mTc-MDP or CT both have high diagnostic efficiency for bone metastase of breast cancer.

[Application progress of 18F-FDG positron emission tomograph in differentiated thyroid cancer].

Positron emission tomography (PET) is a highly sensitive and low invasive technology for cancer biological imaging. Integrated PET/computed tomography (PET/CT) cameras combine functional and anatomical information in a synergistic manner that improves diagnostic interpretation. The role of 18F FDG PET/CT in differentiated thyroid cancer (DTC) is well established, particularly in patients presenting with elevated thyroglobulin (Tg) levels and negative radioactive iodine scan. This review presents the evidence supporting the use of 18F FDG PET/CT throughout the diagnosis and management of thyroid cancer, and provides suggestions for its clinical uses.

FDG PET/CT may replace bone marrow biopsy for the evaluation of bone marrow involvement in selected mature T- and natural killer-cell lymphomas: A meta-analysis.

PURPOSE: To systematically determine the role of FDG PET/CT for the diagnosis of bone marrow involvement in mature T- and natural killer (NK)-cell lymphomas. METHODS: The PubMed, Embase and Cochrane Library databases were searched to identify eligible studies. Data extraction and quality assessment were independently conducted. Then, pooled diagnostic performance with the 95 % confidence interval (CI) was calculated and further analyzed based on different interpretation criteria, tumor type and stage. RESULTS: Fifteen studies were eventually included for quantitative analysis. Overall, the methodological quality of included studies was acceptable. For detecting bone marrow involvement, FDG PET/CT achieved a poor sensitivity of 0.62 (95 % CI, 0.48-0.71) and a reasonable specificity of 0.92 (95 % CI, 0.87-0.96). Similar performance was observed for the specific type of extranodal NK/T-cell lymphoma (ENKTCL). In early-stage patients revealed by PET/CT, extremely small proportion (2/777) showed positive bone marrow biopsy, especially for the specific type of ENKTCL, whereas in advanced-stage patients, the specificity of FDG PET/CT dropped to 0.77 (95 % CI, 0.72-0.82). Regarding the interpretation, both diffuse and focal increased uptake patterns as positivity may result in increased sensitivity but decreased specificity compared with focal pattern alone as positivity. CONCLUSIONS: FDG PET/CT demonstrated excellent negative predictive value for detecting marrow involvement in early-stage patients with mature T- and NK-cell lymphomas, especially the ENKTCL. Conversely, FDG PET/CT showed poor performance for the diagnosis of bone marrow involvement in advanced-stage patients.

[Advancement of studies on second mitochondrial activator of caspase].

Smac is a mitochondrial protein that interacts with inhibitor of apoptosis proteins (IAPs). Upon apoptotic stimuli, the Smac is released into the cytoplasm to inhibit the capase-binding activity of IAPs. The low expression of Smac in tissues has been reported existing in various cancers. Smac plays key roles in prognosis and chemoradiotherapy resistance of malignant tumor besides neoplasm genesis and growth. Furthermore, Smac may be a molecular therapeutic target in cancer patients. Overexpression of Smac by transfecting extrinsic Smac gene or Smac mimetic into tumor cell can improve their sensitivity to radiotherapy and chemotherapy, which has great significance to the treatment of tumor. Our review will focus on the roles of Smac in structure, pro-apoptotic mechanism, tissue distribution and cancer treatment.

[Development of a predicting model to estimate the probability of malignancy of solitary pulmonary nodules].

OBJECTIVE: To evaluate the role of (18)F-FDG PET/CT in characterizating solitary pulmonary nodule (SPN) and bone lesions. METHODS: 105 patients with a SPN smaller than 30 mm in axial diameter were recruited for this study. PET/CT images were obtained 60 min after intravenous injection of (18)F-FDG. Logistic regression analysis was performed to identify clinical predictors of SPN malignancy including age, sex, smoking history, malignant history, family history, symptoms, size, location, CT appearances, (18)F-FDG uptake, and to develop a clinical prediction model to estimate the probability of malignancy in the patients with SPN. The model fit was evaluated and the area under curve (AUC) of receiver operating characteristic (ROC) was used to evaluate the power of the model. RESULTS: The logistic regression analysis indicated that male, a positive smoking history, older age, larger nodule diameter, nodule with specula and nodule with high (18)F-FDG uptake were more likely to have malignant SPN. The clinical prediction model is described by the following equation: Logit(P) = -8.722 + 2.448 (gender) + 2.023(smoking) + 0. 851(age) + 1.057 (diameter) + 2.432 (spiculation) + 1.502 (FDG uptake). The AUC of the model was 0.892 (95% confidence interval 0.817 - 0.941). The prediction model had high accuracy in predicting malignant SPN, with 90.2%, 84.1 % and 87.6% sensitivity, specificity and accuracy respectively when the cut off value was set at 0.67. CONCLUSION: The prediction model is valid in predicting the probability of malignant SPN.

[Clinical application of recombinant human thyroid-stimulating hormone in management of differentiated thyroid carcinoma].

Traditionally, during the follow-up and in order to receive 131 I therapy, patients with differentiated thyroid carcinoma (DTC) have to withdraw from using thyroid hormone. The hypothyroidism induced by hormone withdrawal can negatively affect the quality-of-life (QOL) of DTC patients. Without the hormone withdrawal, recombinant human thyroid-stimulating hormone-aided management of DTC patients can effectively obviate the consequences of hypothyroidism. This review will focus on the clinical application of recombinant human thyroid-stimulating hormone (rhTSH) in the management of DTC patients.

[Research on comparison of thyroglobulin autoantibody interference in measurement of thyroglobulin between electrochemiluminescent assay and radioimmunoassay].

This paper is aimed to evaluatethe thyroglobulin autoantibody (TgAb) interference in measurement of thyroglobulin (Tg) between electrochemiluminescent assay (ECLIA) and radioimmunoassay (RIA). Tg and TgAb of 84 sera, including 22 Graves' hyperthyroidism(GD), 24 Hashimoto thyroiditis (HT) and 38 differentiated thyroid carcinomas (DTC), were measured by RIA and ECLIA, respectively. Recovery tests were carried out in 3 groups. The sera samples of the first group were added 3 different amount of Tg calibrator; the sera samples of the second group were diluted 5 times, then 100 ng/ml Tg calibrator was added; the sera samples of the third group were divided into different subgroups depending on TgAb concentration with adding 100 ng/ml Tg calibrator,Tg and TgAb were measured in each dilution by ECLIA and RIA. Recovery rate was calculated. The Tg and TgAb values measured by ECLIA were correlated with that measured by RIA (r = 0.676, P = 0.000; r = 0.677, P = 0.000, respectively). When TgAb concentration increased, the Tg values decreased by ECLIA and increased by RIA. The TgAb values were decreased when sera were diluted, and the Tg values also reduced by RIA and increased by ECLIA. The added different amount of Tg calibrator had not significant influence on Tg recovery rates. When TgAb concentration increased, recovery rates of Tg were decreased by ECLIA and increased by RIA. When sera were diluted, the recovery rates of Tg were increased by ECLIA while decreased by RIA. RIA and ECLIA have good correlation with Tg measurement in 10-400 ng/ml. ECLIA has wider measuring range and higher sensitivity than RIA. RIA and ECLIA have good correlation with TgAb measurement. When TgAb is positive, Tg values are underestimated by ECLIA and overestimated by RIA. When sera are diluted, Tg value and the recovery rate are increasing by ECLIA and decreased by RIA. Recovery test can not efficiently rectify Tg value when TgAb is positive.

[Genetic alterations in MAPK and PI3K/Akt signaling pathways and the generation, progression, diagnosis and therapy of thyroid cancer].

The mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) and phoshoinositide-3-kinase/protein kinase B (PI3K/Akt) signaling pathways play a major role in regulating cell growth, proliferation and apoptosis, via transmission of cell signals to cell nucleus. The genes, coding the MAPK/ERK and PI3K/Akt signaling cascade proteins, are significantly mutated in thyroid cancer. Genetic alternations contribute to aberrant activations and interaction of MAPK/ERK and PI3K/Akt signaling pathways in consequence of malignant follicular cell transformation and progression. This review focuses mainly on the role of genetic alterations in coding MAPK/ERK and PI3K/Akt signaling pathway proteins in generation, progression and diagnosis of thyroid cancer. Moreover, it additionally points out a therapeutic potential in restoring iodine avidity of thyroid cancer cells for radionuclide targeted treatment, by synergistically inhibiting activity of signaling pathways.

Lymphoscintigraphic Findings of Scrotal Lymphangioma.

ABSTRACT: As congenital lymphatic malformations, lymphangiomas commonly occur in the neck, tongue, and extremities, whereas scrotum is one of the least frequent sites. For this lymphatic flow disease, lymphoscintigraphy is regarded as a useful imaging method. Herein, in a child with scrotal cysts, scrotal region activity was detected in lymphoscintigraphy, consistent with likely lymphatic disorder. The postsurgical pathology confirmed the diagnosis of lymphangioma.

Recurrent Ovarian Cancer Presenting as a Solitary Chest Wall Metastasis Revealed by FDG PET/CT.

ABSTRACT: A 55-year-old woman who was diagnosed with ovarian cancer 4 years ago complained of back pain for 1 month, and the CA-125 level was elevated. FDG PET/CT was then performed for restaging, and the images revealed a hypermetabolic mass in the right posterior chest wall. Postsurgical pathology confirmed metastasis from ovarian cancer.

Solitary Fibrous Tumor of the Bone Detected by FDG PET/CT.

ABSTRACT: Solitary fibrous tumor as a rare mesenchymal tumor can occur in a wide variety of body sites, including serosal membranes, liver, lung, and deep soft tissues; however, primary tumor arising in bone is rarely documented. Herein, we reported the MRI, bone scan, and FDG PET/CT findings of a primary spinal solitary fibrous tumor in a 39-year-old woman.

Predictive Value of Gross Extranodal Extension for Differentiated Thyroid Carcinoma Persistence/Recurrence.

OBJECTIVE: We systematically investigated the predictive value of gross extranodal extension (gENE) for differentiated thyroid carcinoma persistence/recurrence. STUDY DESIGN: Retrospective study. SETTING: A tertiary care hospital. METHODS: This study was divided into 2 groups according to gENE status: the gENE group and non-gENE group. We compared the disease persistence/recurrence rates of these 2 groups in the entire cohort and by individual risk group (intermediate/high risk), analyzed whether gENE was an independent risk factor for disease persistence/recurrence, and explored the impact of gENE-specific features on disease persistence/recurrence. RESULTS: There were 989 patients who satisfied the inclusion criteria: 57 patients in the gENE group and 932 in the non-gENE group. The disease persistence/recurrence rate of the gENE group was higher than that of the non-gENE group in the entire cohort and by individual risk group (P < .05 for each). Unexpectedly, the outcomes of the gENE group with intermediate risk were similar to those of the non-gENE group with high risk (P = .72). For the entire cohort, gENE was an independent predictor for disease persistence/recurrence (odds ratio, 2.89; 95% CI, 1.39-6.00; P = .005). Specific features of gENE (P > .05 for each) were not related to disease persistence/recurrence. CONCLUSION: Patients with gENE and intermediate risk might be regraded as high risk. Specific features of gENE have no impact on disease persistence/recurrence.

[Pharmacokinetics and tissue distribution of long circulating liposomes in rabbits and mice].

OBJECTIVE: To investigate the pharmacokinetic profiles and tissue distribution of long circulating liposome formulations-anionic, cationic, and neutral long circulating liposomes (NA, PA, A-D) in rabbits and mice. METHODS: Conventional liposomes (CA) encapsulated with 125I-bcl-2/bcl-xl ASON and free 125I-bcl-2/bcl-xl ASON (FA) were intravenously administered to rabbits and mice. The blood samples from rabbits and organs from mice were collected, respectively. The radioactivity of the blood and tissues samples were measured. RESULTS: The clearance of the four kinds of liposomes and FA exhibited bicompartmental behaviors. Compared with others, NA demonstrated favourable pharmacokinetic properties characterized with enhancement of T9(1/2 alpha) and T(1/2 beta), increased area under concentration-time curve, and decreased liver uptake. Higher uptake in the liver, spleen and kidney of mice and lower uptake in the brain, muscle, and bone of mice were observed shortly after intravenous injection of the four different kinds of liposomes and FA. A 30% decrease in uptake of NA was found in the liver of mice four hours after intravenous injection compared with the uptake of CA. No significant differences were found in the uptake of the four kinds of liposomes in the spleen of mice (P > 0.05). CONCLUSION: NA is promising as a carrier for radio-antisense therapy.