Comparing the diagnostic performance of radiotracers in prostate cancer biochemical recurrence: a systematic review and meta-analysis.

OBJECTIVES: To systematically assess the early detection rate of biochemical prostate cancer recurrence using choline, fluciclovine, and PSMA. METHODS: Under the guidance of the Preferred Reporting Items for Systematic reviews and Meta-Analysis Diagnostic Test Accuracy guidelines, literature that assessed the detection rates (DRs) of choline, fluciclovine, and PSMA in prostate cancer biochemical recurrence was searched in PubMed and EMBASE databases for our systematic review from 2012 to July 15, 2021. In addition, the PSA-stratified performance of detection positivity was obtained to assess the DRs for various methods, including fluciclovine, PSMA, or choline PET/CT, with respect to biochemical recurrence based on different PSA levels. RESULTS: In total, 64 studies involving 11,173 patients met the inclusion criteria. Of the studies, 12, 7, and 48 focused on choline, fluciclovine, and PSMA, respectively. The pooled DRs were 24%, 37%, and 44%, respectively, for a PSA level less than 0.5 ng/mL (p < 0.001); 36%, 44%, and 60% for a PSA level of 0.5-0.99 ng/mL (p < 0.001); and 50%, 61%, and 80% for a PSA level of 1.0-1.99 ng/mL (p < 0.001). The DR with 18F-labeled PSMA was higher than that with 68Ga-labeled PSMA, and the DR was 58%, 72%, and 88% for PSA levels < 0.5 ng/mL, 0.5-0.9 ng/mL, and 1.0-1.99 ng/mL, respectively. CONCLUSION: The DRs of PSMA-radiotracers were greater than those of choline-radiotracers and fluciclovine-radiotracers at the patient level. 18F-labeled PSMA achieved a higher DR than 68Ga-labeled PSMA. KEY POINTS: • The DRs of PSMA-radiotracers were greater than those of choline-radiotracers and fluciclovine-radiotracers at the patient level. • 18F-labeled PSMA achieved a higher DR than 68Ga-labeled PSMA.

Rare monolocular intrahepatic biliary cystadenoma: A case report.

BACKGROUND: Intrahepatic biliary cystadenoma (IBC) is a rare benign hepatic tumor that is often misdiagnosed as other hepatic cystic diseases. Therefore, imaging examinations are required for preoperative diagnosis. Contrast-enhanced ultrasound (CEUS) has gained increasing popularity as an emerging imaging modality and it is considered the primary method for screening IBC because of its specificity of performance. We describe an unusual case of monolocular IBC and emphasize the performance of CEUS. CASE SUMMARY: A 45-year-old man complained of epigastric pain lasting 1 wk. He had no medical history of hepatitis, liver cirrhosis or parasitization. Physical examination revealed a mass of approximately 6 cm in size in the upper abdomen below the subxiphoid process. Tumor marker tests found elevated CA19-9 levels (119.3 U/mL), but other laboratory tests were unremarkable. Ultrasound and computerized tomography revealed a round thick-walled mass measuring 83 mm × 68 mm located in the left lateral lobe of the liver that lacked internal septations and manifested as a monolocular cystic structure. CEUS demonstrated that in the arterial phase, the anechoic area manifested as a peripheral ring with homogeneous enhancement. The central part presented with no enhancement. During the portal phase, the enhanced portion began to subside but was still above the surrounding liver tissue. The patient underwent left partial liver lobectomy and recovered well without tumor recurrence or metastasis. Eventually, the results of pathological examination confirmed IBC. CONCLUSION: A few IBC cases present with monolocular characteristics, and the lack of intracystic septa in imaging performance cannot exclude IBC.

Development and Validation of a 18F-FDG PET-Based Radiomic Model for Evaluating Hypermetabolic Mediastinal-Hilar Lymph Nodes in Non-Small-Cell Lung Cancer.

BACKGROUND: Accurate evaluation of lymph node (LN) status is critical for determining the treatment options in patients with non-small cell lung cancer (NSCLC). This study aimed to develop and validate a 18F-FDG PET-based radiomic model for the identification of metastatic LNs from the hypermetabolic mediastinal-hilar LNs in NSCLC. METHODS: We retrospectively reviewed 259 patients with hypermetabolic LNs who underwent pretreatment 18F-FDG PET/CT and were pathologically confirmed as NSCLC from two centers. Two hundred twenty-eight LNs were allocated to a training cohort (LN = 159) and an internal validation cohort (LN = 69) from one center (7:3 ratio), and 60 LNs were enrolled to an external validation cohort from the other. Radiomic features were extracted from LNs of PET images. A PET radiomics signature was constructed by multivariable logistic regression after using the least absolute shrinkage and selection operator (LASSO) method with 10-fold cross-validation. The PET radiomics signature (model 1) and independent predictors from CT image features and clinical data (model 2) were incorporated into a combined model (model 3). A nomogram was plotted for the complex model, and the performance of the nomogram was assessed by its discrimination, calibration, and clinical usefulness. RESULTS: The area under the curve (AUC) values of model 1 were 0.820, 0.785, and 0.808 in the training, internal, and external validation cohorts, respectively, showing good diagnostic efficacy for lymph node metastasis (LNM). Furthermore, model 2 was able to discriminate metastatic LNs in the training (AUC 0.780), internal (AUC 0.794), and external validation cohorts (AUC 0.802), respectively. Model 3 showed optimal diagnostic performance among the three cohorts, with an AUC of 0.874, 0.845, and 0.841, respectively. The nomogram based on the model 3 showed good discrimination and calibration. CONCLUSIONS: Our study revealed that PET radiomics signature, especially when integrated with CT imaging features, showed the ability to identify true and false positives of mediastinal-hilar LNM detected by PET/CT in patients with NSCLC, which would help clinicians to make individual treatment decisions.

Distinguishing between benign and malignant breast lesions using diffusion weighted imaging and intravoxel incoherent motion: A systematic review and meta-analysis.

PURPOSE: We sought to evaluate the diagnostic performance of diffusion weighted imaging (DWI) and intravoxel incoherent motion (IVIM) for distinguishing between benign and malignant breast tumors by performing a meta-analysis. METHODS: We comprehensively searched the electronic databases PubMed and Embase from January 2000 to April 2020 for studies in English. Studies were included if they reported the sensitivity and specificity for identifying benign and malignant breast lesions using DWI or IVIM. Studies were reviewed according to QUADAS-2. The data inhomogeneity and publication bias were also assessed. In order to explore the influence of different field strengths and different b values on diagnostic efficiency, we conducted subgroup analysis. RESULTS: We analyzed 79 studies, which included a total of 6294 patients with 4091 malignant lesions and 2793 benign lesions. Overall, the pooled sensitivity and specificity of ADC for detecting malignant breast tumors were 0.87 (0.86-0.88) and 0.80 (0.78-0.81), respectively. The PLR was 5.09 (4.16-6.24); the NLR was 0.15 (0.13-0.18); and the DOR was 38.95 (28.87-52.54). The AUC value was 0.9297. The highest performing parameter for IVIM was tissue diffusivity (D), and the pooled sensitivity and specificity was 0.85 (0.82-0.88) and 0.87(0.83-0.90), respectively; the PLR was 5.65 (3.91-8.18); the NLR was 0.17 (0.12-0.26); and the DOR was 38.44 (23.57-62.69). The AUC value was 0.9265. Most of parameters demonstrated considerable statistically significant heterogeneity (P < 0.05, I2>50 %) except the pooled DOR, PLR of D and the pooled DOR and NLR of D*. CONCLUSIONS: Our meta-analysis indicated that DWI and IVIM had high sensitivity and specificity in the differential diagnosis of breast lesions; and compared with DWI, IVIM could not further increase the diagnostic performance. There was no significant difference in diagnostic accuracy.

Thalidomide Reduces Activation of Murine Pancreatic Stellate Cells by Inhibiting the TGF-ß/Smad Pathway.

OBJECTIVE: The aim of this study was to investigate the effects and mechanism of thalidomide on pancreatic stellate cell (PSC) activation in mice and to find the optimal timing of thalidomide administration. METHODS: PSCs, isolated from mouse pancreas tissue, were divided into five groups with specific treatments: (A) control PSCs (PSC), (B) PSCs induced by TGF-ß1 (PSC+TGF-ß1), (C) PSCs induced by TGF-ß1 followed by thalidomide (PSC+TGF-ß1+Thalidomide), (D) PSCs receiving TGF-ß1 and thalidomide simultaneously (PSC+(TGF-ß1+Thalidomide)), and (E) PSCs treated with thalidomide only (PSC+Thalidomide). We measured the effects of thalidomide on PSC activation by detecting the expression of α-SMA, collagen type I, and the TGF-ß/Smad pathway through quantitative real-time PCR and Western blot analysis. RESULTS: Compared with TGF-ß1 alone, thalidomide significantly inhibited PSC activation by reducing α-SMA expression (P<0.05) and decreasing collagen type I deposition (P<0.05). PSCs treated with thalidomide alone showed lower expression of α-SMA and collagen type I than those treated with thalidomide and TGF-ß1 at random order (P<0.01). Thalidomide downregulated TGF-ß1 and Smad3 and upregulated Smad7 (P<0.05). CONCLUSION: Thalidomide could repress PSC activation and alleviate fibrosis by regulating the TGF-ß/Smad pathway. Preventive use of thalidomide had maximum effect, and there was no evidence for the reversal of the activation of quiescent PSCs.

Feasibility of customizing titanium implant with three-dimensional CT imaging of low dose in skull.

OBJECT: To explore the feasibility and practicability of making virtual three-dimensional model of skull defect and customizing titanium implant by skull three-dimensional CT examination of low dose. METHODS: Sixty patients with skull defects who underwent skull three-dimensional CT before cranioplasty were randomly divided into 4 groups: group A (conventional dose 120 peak Kilovoltage (kVp), 150 tube current time product (mAs)), low dose group B (120 kVp, 50 mAs), low dose group C (100 kVp, 50 mAs), low dose group D (100 kVp, 30 mAs). After the scanning, we compared radiation doses and image quality among the groups. The CT data were sent to the reconstruction company to produce accurate titanium implants, and neurosurgeons performed cranioplasty. After the operation, patients immediately underwent head CT scans to confirm the accuracy of the implantation position, and a series of clinical functions were evaluated. RESULTS: There were significant differences in dose length product (DLP) and effective dose (ED) among the 4 groups (P < .001). The volume CT dose index (CDTIvol), DLP, and ED in group D were, respectively, 87.1%, 86.9%, and 87.3% lower than those in group A (P < .001). All images quality were at or above the general level, and there was no statistical difference (P > .05). Titanium implants were successfully manufactured, every cranioplasty was carried out smoothly, and the clinical function of patients recovered well. CONCLUSION: Customizing titanium implant with three-dimensional CT imaging of low dose in skull not only met the clinical requirements, but also significantly reduced the radiation dose and hazard.

The Diagnostic Accuracy of Magnetic Resonance Imaging in Restaging of Rectal Cancer After Preoperative Chemoradiotherapy: A Meta-Analysis and Systematic Review.

OBJECTIVE: To evaluate the overall diagnostic value of magnetic resonance imaging (MRI) in restaging of rectal cancer after preoperative chemoradiotherapy based on qualified studies. METHODS: PubMed, Cochrane, and EMBASE database were searched by the index words to identify the qualified studies, and relevant literature sources were also searched. The latest research was done in April 2019. Heterogeneity of the included studies was tested, which was used to select proper effect model to calculate pooled weighted sensitivity, specificity, and diagnostic odds ratio (DOR). Summary receiver operating characteristic (SROC) analyses were also performed. RESULT: Nineteen studies with 1262 patients were involved in the meta-analysis exploring the diagnostic accuracy of MRI for rectal cancer. The diagnostic accuracy of MRI in T3-T4 rectal cancer was as follows: sensitivity, 81% (95% confidence interval [CI], 67%-90%); specificity, 67% (95% CI, 51%-80%); positive likelihood ratio, 2.48 (95% CI, 1.57-3.91); negative likelihood ratio, 0.28 (95% CI, 0.15-0.52); global DOR, 6.86 (95% CI, 3.07-15.30); the area under the SROC was high (0.81; 95% CI, 0.78-0.84). The diagnostic accuracy of MRI in lymphatic metastasis of rectal cancer was as follows: sensitivity, 77% (95% CI, 65%-86%); specificity, 77% (95% CI, 63%-87%); positive likelihood ratio, 3.40 (95% CI, 2.07-5.59); negative likelihood ratio, 0.30 (95% CI, 0.20-0.45); DOR, 10.81 (95% CI, 4.99-23.39); area under the SROC was high (0.84; 95% CI, 0.80-0.87). CONCLUSIONS: This study provides a systematic review and meta-analysis of diagnostic accuracy studies of MRI for rectal cancer. The results indicate that MRI is a highly accurate diagnostic tool for rectal cancer T3-T4 staging and N staging but sensitivity and specificity are not high.

[Evaluation of Uterine Tumor Angiogenesis with Quantitative Magnetic Resonance Imaging Perfusion Parameters].

The development and metastasis of uterine tumors depend highly on tumor angiogenesis. Multiphase dynamic contrast-enhanced magnetic resonance imaging can quantitatively describe the hemodynamic changes of uterine tumors based on a variety of tracer kinetic models and time-signal curves and by simulating the distribution of contrast inside and outside the blood vessels. Functional parameters can accurately and noninvasively assess tumor angiogenesis. It provides a non-invasive functional evaluation method for the differential diagnosis,staging,response evaluation,and prognostic prediction of uterine tumors.

SPINK1, PRSS1, CTRC, and CFTR Genotypes Influence Disease Onset and Clinical Outcomes in Chronic Pancreatitis.

OBJECTIVES: Rare pathogenic variants in the SPINK1, PRSS1, CTRC, and CFTR genes have been strongly associated with a risk of developing chronic pancreatitis (CP). However, their potential impact on the age of disease onset and clinical outcomes, as well as their potential interactions with environmental risk factors, remain unclear. These issues are addressed here in a large Chinese CP cohort. METHODS: We performed targeted next-generation sequencing of the four CP-associated genes in 1061 Han Chinese CP patients and 1196 controls. To evaluate gene-environment interactions, the patients were divided into three subgroups, idiopathic CP (ICP; n = 715), alcoholic CP (ACP; n = 206), and smoking-associated CP (SCP; n = 140). The potential impact of rare pathogenic variants on the age of onset of CP and clinical outcomes was evaluated using the Kaplan-Meier model. RESULTS: We identified rare pathogenic genotypes involving the SPINK1, PRSS1, CTRC, and/or CFTR genes in 535 (50.42%) CP patients but in only 71 (5.94%) controls (odds ratio = 16.12; P < 0.001). Mutation-positive patients had significantly earlier median ages at disease onset and at diagnosis of pancreatic stones, diabetes mellitus and steatorrhea than mutation-negative ICP patients. Pathogenic genotypes were present in 57.1, 39.8, and 32.1% of the ICP, ACP, and SCP patients, respectively, and influenced age at disease onset and clinical outcomes in all subgroups. CONCLUSIONS: We provide evidence that rare pathogenic variants in the SPINK1, PRSS1, CTRC, and CFTR genes significantly influence the age of onset and clinical outcomes of CP. Extensive gene-environment interactions were also identified.

Imaging findings of gastric plexiform fibromyxoma with a cystic change: A case report and review of literature.

RATIONALE: Plexiform fibromyxoma (PF) is an extremely rare mesenchymal tumor of the stomach, and its radiological findings have not been well described. Here, we analyzed the imaging features of a case of PF. To our knowledge, this is a rare reported case with a remarkable cystic change in the imaging literature. PATIENT CONCERNS: A previously healthy 50-year-old woman presented with a 1-day history of abdominal pain. Then, she underwent computed tomography (CT) and magnetic resonance imaging (MRI). A cystic-solid well-circumscribed extraluminal mass was located in the posterior wall of the gastric upper body. The solid portion appeared as heterogeneous attenuation/intensity with progressive enhancement while the cystic region had no enhancement. DIAGNOSES: The potential for malignancy could not be excluded. INTERVENTIONS: Laparoscopic partial gastric resection was performed. OUTCOMES: Based on pathological findings, a diagnosis of PF was made. The patient was alive without any recurrence or metastasis of the tumor after 2 years of follow-up. LESSONS: As far as we know, a gastric PF with a remarkable cystic change has never been reported. Additionally, the tumor exhibited a progressive enhancement pattern which is a characteristic radiographic feature in our case. Our report may help increase the awareness of this rare but important new disease entity.

Risk factors associated with acute/subacute cerebral infarction in HIV-negative patients with cryptococcal meningitis.

OBJECTIVE: To explore the risk factors associated with acute/subacute cerebral infarction (ASCI) in HIV-negative patients with cryptococcal meningitis (CM). METHODS: This case-control study included 10 HIV-negative CM patients with ASCI and 30 age- and sex-matched HIV-negative control (1:3) CM patients without ASCI. The clinical manifestations and neuroimaging findings were collected. Risk factors for ASCI in the HIV-negative CM patients were confirmed by conditional logistic regression analysis. RESULTS: Among the 10 HIV-negative CM patients with ASCI, all cases had lacunar infarctions. Single infarctions were found in 6 patients, and multiple infarctions in 4. Hydrocephalus (p=0.020, OR=23.77, 95% CI, 1.67-339.33) and smoking (p=0.039, OR=11.63, 95% CI, 1.14-118.96) were found to be independently associated with the occurrence of ASCI. CONCLUSIONS: Hydrocephalus and smoking may increase the risk of ASCI in HIV-negative CM patients. In the clinical course, cerebral infarction should be strongly suspected in CM patients with hydrocephalus or smoking histories.

Dual-input two-compartment pharmacokinetic model of dynamic contrast-enhanced magnetic resonance imaging in hepatocellular carcinoma.

AIM: To investigate the feasibility of a dual-input two-compartment tracer kinetic model for evaluating tumorous microvascular properties in advanced hepatocellular carcinoma (HCC). METHODS: From January 2014 to April 2015, we prospectively measured and analyzed pharmacokinetic parameters [transfer constant (Ktrans), plasma flow (Fp), permeability surface area product (PS), efflux rate constant (kep), extravascular extracellular space volume ratio (ve), blood plasma volume ratio (vp), and hepatic perfusion index (HPI)] using dual-input two-compartment tracer kinetic models [a dual-input extended Tofts model and a dual-input 2-compartment exchange model (2CXM)] in 28 consecutive HCC patients. A well-known consensus that HCC is a hypervascular tumor supplied by the hepatic artery and the portal vein was used as a reference standard. A paired Student's t-test and a nonparametric paired Wilcoxon rank sum test were used to compare the equivalent pharmacokinetic parameters derived from the two models, and Pearson correlation analysis was also applied to observe the correlations among all equivalent parameters. The tumor size and pharmacokinetic parameters were tested by Pearson correlation analysis, while correlations among stage, tumor size and all pharmacokinetic parameters were assessed by Spearman correlation analysis. RESULTS: The Fp value was greater than the PS value (FP = 1.07 mL/mL per minute, PS = 0.19 mL/mL per minute) in the dual-input 2CXM; HPI was 0.66 and 0.63 in the dual-input extended Tofts model and the dual-input 2CXM, respectively. There were no significant differences in the kep, vp, or HPI between the dual-input extended Tofts model and the dual-input 2CXM (P = 0.524, 0.569, and 0.622, respectively). All equivalent pharmacokinetic parameters, except for ve, were correlated in the two dual-input two-compartment pharmacokinetic models; both Fp and PS in the dual-input 2CXM were correlated with Ktrans derived from the dual-input extended Tofts model (P = 0.002, r = 0.566; P = 0.002, r = 0.570); kep, vp, and HPI between the two kinetic models were positively correlated (P = 0.001, r = 0.594; P = 0.0001, r = 0.686; P = 0.04, r = 0.391, respectively). In the dual input extended Tofts model, ve was significantly less than that in the dual input 2CXM (P = 0.004), and no significant correlation was seen between the two tracer kinetic models (P = 0.156, r = 0.276). Neither tumor size nor tumor stage was significantly correlated with any of the pharmacokinetic parameters obtained from the two models (P > 0.05). CONCLUSION: A dual-input two-compartment pharmacokinetic model (a dual-input extended Tofts model and a dual-input 2CXM) can be used in assessing the microvascular physiopathological properties before the treatment of advanced HCC. The dual-input extended Tofts model may be more stable in measuring the ve; however, the dual-input 2CXM may be more detailed and accurate in measuring microvascular permeability.

Increased expression of SPRY4-IT1 predicts poor prognosis and promotes tumor growth and metastasis in bladder cancer.

INTRODUCTION: long non-coding RNAs (lncRNAs) are emerging as new regulators in the cancer paradigm, the involvement of lncRNAs in urothelial carcinoma of the bladder (UCB) is just beginning to be studied. In this study, we focused on lncRNA SPRY4-IT1 and investigated its expression pattern, clinical significance, and biological function in UCB. METHODS: SPRY4-IT1 expression in UCB tissues was examined by quantitative Real-time PCR (qRT-PCR) and its correlation with clinicopathological features and patient prognosis was later analyzed. Moreover, in vitro assays were performed to explore its role in bladder cancer progression. RESULTS: SPRY4-IT1 expression was elevated in UCB tissues, and SPRY4-IT1 levels were highly positively correlated with histological grade, tumor stage, and lymph node metastasis and reduced overall survival. A multivariate analysis showed that SPRY4-IT1 expression is an independent prognostic factor of overall survival in patients with UCB. Additionally, the results of in vitro assays showed that the suppression of SPRY4-IT1 expression in bladder cancer cells significantly inhibit cell proliferation, migration, and invasion. CONCLUSIONS: Our data suggested that lncRNA SPRY4-IT1 is a novel molecule involved in bladder cancer progression, which provide a potential prognostic biomarker and therapeutic target.

Imaging findings of primary gastric plasmacytoma: a case report.

Primary gastric plasmacytoma (GP) is a rare extramedullary plasmacytoma with clinical and imaging features that are common among other gastric tumors, such as gastric adenocarcinomas, gastric stromal tumors, and lymphomas. Here, we present a histologically confirmed case of primary GP examined with biphasic computed tomography (CT), magnetic resonance imaging (MRI), and endosonography. A well-circumscribed extraluminal mass appearing as homogeneous attenuation/intensity with gradual enhancement was identified on biphasic enhancement CT and MRI. This mass was hyperintense on diffusion-weighted imaging and hypointense on the apparent diffusion coefficient map, implying that water diffusion in the mass was restricted. In addition, endosonography indicated a low echogenic mass in the gastric wall. These imaging findings increase the available knowledge about imaging of this disease and provide valuable information for differentiating primary GP from common gastric tumors.

[Correlationship between chemokines and oxidative stress in chronic hepatitis B].

OBJECTIVE: The aim of this study is to investigate the possible associations of chemokines IP-10, Rantes and oxidative stress in chronic hepatits B (CHB). METHODS: 70 CHB patients and 10 healthy controls were enrolled in the study. Enzyme-linked immunosorbent assay (ELISA) was used to detect the serum levels of IFN-gamma-inducible protein-10 (IP-10) and regulated on activation normal T-cell-expressed and secreted (Rantes) and oxidative stress parameters (glutathione, GSH; glutathione disulfide, GSSG). Correlationship were analyzed by Spearman's rank correlation. RESULT: The levels of IP-10 and Rantes were higher in CHB patients than healthy controls, and strong positive associations were found between IP-10/Rantes and alanine aminotransferase (ALT). The levels of GSH and GSH/GSSG were lower in CHB patients than healthy controls, and GSH and GSH/GSSG were negatively correlated with ALT. The levels of IP-10 and Rantes were negatively correlated with GSH and GSH/GSSG respectively. CONCLUSION: Strong associations were found between chemokines and oxidative stress which participated in the pathogenesis of CHB.

[Detection of ED1 gene mutations in six pedigrees with hypohidrotic ectodermal dysplasia].

OBJECTIVE: To identify potential mutations of ED1 gene in six pedigrees with hypohidrotic ectodermal dysplasia (HED), and to provide genetic counseling and prenatal diagnosis. METHODS: Eight coding exons of ED1 gene of patients with clinically diagnosed HED and their relatives were amplified by polymerase chain reaction (PCR). The products were further analyzed by direct sequencing. RESULTS: Various mutations of ED1 gene were detected, which included R153C, A349T, G299S, A349T and X392Q. Heterozygous double peaks at the same position were found in female carriers. Deletion of exon 9 was detected in one pedigree. R153C, X392Q and deletion of exon 9 were first identified in ethnic Han Chinese. CONCLUSION: The identified mutations of ED1 gene may be responsible for the disease. Genetic counseling, prenatal diagnosis and carrier screening are now available for these families.

[Correlation of the expressions of VEGF-C and VEGFR-3 to the pathological grade of prostate cancer].

OBJECTIVE: To investigate the correlation of the expression of VEGF-C and VEGFR-3 to the pathological grade of human prostate cancer. METHODS: Immunohistochemistry was used to detect the expression of VEGF-C and VEGFR-3 in 25 cases of prostate cancer tissues. RESULTS: The total positivity rates of VEGF-C and VEGFR-3 were 80% and 76% in these cancer tissues, respectively. The positivity rates of VEGF-C was 94.7% in the 19 cases with Gleason scores no less than 6 (group I), significantly higher than the rate (33%) in the 6 cases with Gleason scores between 4 and 6 (group II) (P<0.01). The positivity rates for VEGFR-3 also showed a significant difference between groups I and II (89.5% vs 33.3%, P<0.05). The expression level of VEGF-C was correlated to the Gleason score of prostate cancer (R=0.436, P<0.05), and the correlation between VEGFR-3 and the Gleason score was even more obvious (R=0.608, P<0.01). Their expressions, however, did not show any correlations to the patients age, PSA or the volume of the prostate. CONCLUSION: VEGF-C and VEGFR-3 may serve as new markers for evaluating the malignancy of prostate cancer with Gleason score not less than 4.

Natural gas and indoor air pollution: a comparison with coal gas and liquefied petroleum gas.

OBJECTIVE: The study was designed to compare the combustion products of coal gas, liquefied petroleum gas and natural gas in relation to indoor air pollution. METHODS: Regular pollutants including B(a)P were monitored and 1-hydroxy pyrene were tested in urine of the enrolled subjects. Radon concentrations and their changes in four seasons were also monitored in the city natural gas from its source plant and transfer stations to final users. To analyze organic components of coal gas, liquefied petroleum gas and natural gas, a high-flow sampling device specially designed was used to collect their combustion products, and semi-volatile organic compounds contained in the particles were detected by gas chromatograph-mass spectrograph (GC/MS). RESULTS: Findings in the study showed that the regular indoor air pollutants particles and CO were all above the standard in winter when heating facilities were operated in the city, but they were lowest in kitchens using natural gas; furthermore, although NO2 and CO2 were slightly higher in natural gas, B(a)P concentration was lower in this group and 1-hydroxy pyrene was lowest in urine of the subjects exposed to natural gas. Organic compounds were more complicated in coal gas and liquefied petroleum gas than in natural gas. The concentration of radon in natural gas accounted for less than 1% of its effective dose contributing to indoor air pollution in Beijing households. CONCLUSION: Compared to traditional fuels, gases are deemed as clean ones, and natural gas is shown to be cleaner than the other two gases.