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Rectal adenocarcinoma is a common malignant tumor of the digestive tract. However, it is difficult to obtain tumor microstructural information using conventional magnetic resonance imaging (MRI). Dynamic contrast-enhanced (DCE)-MRI and intravoxel incoherent motion (IVIM) have been used in tumor research. The present study aimed to explore the application of DCE-MRI and IVIM in the risk stratification of resectable rectal adenocarcinoma. To achieve this, 75 patients with rectal adenocarcinoma confirmed via postoperative pathological examination who underwent high-resolution MRI, IVIM and DCE-diffusion-weighted imaging before surgery were retrospectively enrolled and divided into very low-risk (19 cases), low-risk (29 cases) and medium-risk (27 cases) groups. The quantitative parameters of DCE-MRI and IVIM were obtained using the GenIQ and Medical Imaging Interaction Toolkit software, respectively. One-way analysis of variance or the Kruskal-Wallis H test were used to analyze the differences in the measured parameters between the different risk groups. Receiver operating characteristic curves were used to analyze the diagnostic efficacy of each parameter. The differences in rate constant (Kep), perfusion fraction (f) and false diffusion coefficient (D*) between the different risk stratification groups were statistically significant (P<0.05). When the very low- and low-risk groups were compared, f + D* had the highest diagnostic efficiency [area under the curve (AUC)=0.719], with a sensitivity and specificity of 100 and 51.70%, respectively. When the low- and medium-risk groups were compared, Kep had the highest diagnostic efficiency (AUC=0.602), with a sensitivity and specificity of 72.41 and 55.56%, respectively. When the very low-risk and medium-risk groups were compared, Kep + f + D* had the highest diagnostic efficiency (AUC=0.887), with a sensitivity and specificity of 100 and 70.4%, respectively. Thus, DCE-MRI and IVIM can aid the prognostic risk stratification of resectable rectal adenocarcinoma, and Kep, f and D* are potential quantitative imaging parameters for the risk stratification of rectal adenocarcinoma. [ABSTRACT FROM AUTHOR]

This study compared the diagnostic value of molybdenum target and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in different types of breast cancer. A retrospective analysis was performed on 120 female patients with breast cancer admitted to The First Affiliated Hospital of Zhengzhou University from February 2015 to October 2017. All of them underwent DCE-MRI and molybdenum target examination. Postoperatively, the pathological tissues were examined to determine their molecular typing. The sensitivity and diagnostic coincidence rates of Luminal-B breast cancer with different molecular types diagnosed by molybdenum target combined with DCE-MRI were significantly higher than those of molybdenum target or DCE-MRI alone. There were no statistical differences in sensitivity and diagnostic coincidence rates of breast cancer with different molecular types diagnosed by molybdenum target or DCE-MRI alone between the two groups (P>0.05). Molybdenum target combined with DCE-MRI in the diagnosis of different molecular types of breast cancer is better than the single imaging screening, which is of great clinical significance in the development of individualized comprehensive treatment for breast cancer patients and worthy of wide promotion in clinical practice. [ABSTRACT FROM AUTHOR]

The value of pharmacokinetic parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in distinguishing pituitary microadenoma subtypes was investigated in the present study. Pathology and follow-up outcomes were applied as the gold standard for differentiating between 76 patients with pituitary microadenomas (38 prolactin-producing tumors, 17 adrenocorticotropic hormone adenomas and 21 growth hormone-producing tumors) and 20 patients with normal pituitary glands. DCE-MRI was conducted to obtain the following quantitative permeability parameters: Volume transfer constant (Ktrans), rate constant (Kep) and extracellular extravascular volume fraction (Ve). Among the 76 cases included, 61 were visually diagnosed using conventional MRI. The Ktrans, Kep and Ve of the microadenoma cases were 0.472±0.292/min, 0.765±0.359/min and 0.792±0.345, respectively. The Ktrans, Kep and Ve of the normal control group were 0.902±0.238/min, 1.208±0.599/min and 0.928±0.378, respectively. The Ktrans and Kep of patients with microadenomas were significantly lower compared with those of the normal controls (P<0.05). However, the Ve of the two groups did not significantly differ. Subtype differentiation analysis revealed that patients with growth hormone-producing tumors exhibited the highest Ktrans value (P<0.05). Kep significantly differed between growth hormone-producing tumors and the other two subtypes (P<0.05), but did not significantly differ among three subtypes. Receiver-operator characteristic analysis indicated that the area under the curve values of Ktrans and Kep were 0.884 and 0.728, respectively. Sensitivity and specificity were 95.0 and 82.6%, respectively, when Ktrans was set to 0.614/min as the cut-off value, and when the Kep cut-off value was set to 0.985/min, sensitivity and specificity were 60.0 and 81.3%, respectively. In conclusion, Ktrans and Kep derived from DCE-MRI could be applied to detect and identify microadenoma subtypes. Ktrans better reflects the blood perfusion alterations exhibited by patients with different microadenoma subtypes. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) combined with quantitative analysis of diffusion weighted imaging (DWI) for the diagnosis of prostate cancer (PCa). A total of 81 patients with prostatic diseases, including PCa (n=44) and benign prostatic hyperplasia (BPH, n=37), were imaged with T1 weighted imaging (T1WI), T2 weighted imaging (T2WI), DWI and DCE-MRI. The blood vessel permeability parameters volume transfer rate constant (Ktrans), back flow rate constant (Kep), extravascular extracellular space volume fraction (Ve), plasma volume fraction (Vp) and apparent diffusion coefficient (ADC) were measured, and compared between the two groups. The efficiency of these tools for the diagnosis of PCa was analyzed by receiver operating characteristic curve analysis. The efficiency of ADC combined with blood vessel permeability parameters in the diagnosis of PCa was analyzed by logistic regression. The correlation between these parameters and the Gleason score was evaluated by Spearman correlation analysis in the PCa group. The results demonstrated that, compared with the BPH group, Ktrans, Kep, Ve and Vp were higher, and ADC was lower in the PCa group (P<0.05). The combination of Kep and ADC offered the highest diagnosis efficiency [area under the curve (AUC=0.939)]. However, the combination of three parameters did not significantly improve the diagnostic efficiency. A subtle improvement in diagnostic efficiency was observed when four parameters (Ktrans + Kep + Ve + ADC) were combined (AUC=0.940), which was significantly higher than with one parameter. The ADC value of the PCa group was negatively correlated with the primary Gleason pattern, secondary Gleason pattern and the total Gleason score in PCa (r=−0.665, −0.456 and −0.714, respectively; P<0.001). The Vp in the PCa group was slightly negatively correlated with the primary Gleason pattern of PCa (r=−0.385; P<0.05); however, no significant correlation was found with secondary Gleason pattern and the total Gleason score. The present study revealed that the combination of DCE-MRI quantitative analysis and DWI was efficient for PCa diagnosis. This may be because DCE-MRI and DWI can noninvasively detect water motility in tumor tissues and alterations in permeability during tumor neovascularization. The present study demonstrated that Kep and ADC values may be used as predictive parameters for PCa diagnosis, which may help differentiate benign from malignant prostate lesions. [ABSTRACT FROM AUTHOR]

The aim of the current study was to develop a semi-automatic and quantitative method for the analysis of a time-intensity curve (TIC) from breast dynamic contrast-enhanced magnetic resonance imaging. The performance of the proposed method, based on the level set segmentation algorithm, was evaluated by comparison with the traditional method. In the traditional method, the lesion area is delineated manually and the corresponding mean TIC is classified subjectively as one of three washout patterns. In addition, only one quantitative parameter, the maximum slope of increase (MSI), is calculated. In the proposed method, the lesion region was determined semi-automatically and the corresponding mean TIC was categorized quantitatively. In addition to MSI, a number of quantitative parameters were derived from the mean TIC and lesion area, including signal intensity slope (SIslope), initial percentage of enhancement (Einitial), percentage of peak enhancement (Epeak), early signal enhancement ratio (ESER) and second enhancement percentage (SEP). Wilcoxon signed-rank test and receiver operating characteristic analyses were performed for statistical analysis. For TIC categorization the accuracy was 61.54% for the traditional method and 82.05% for the proposed method. Using the proposed method, mean curve accuracies were 84.0% for SIslope, 66.7% for MSI, 66.0% for Einitial, 66.0% for Epeak, 68.0% for ESER and 44.9% for SEP. In the lesion region, the accuracies for the aforementioned parameters were 80.8, 65.4, 66.7, 62.2, 69.2 and 57.1%, respectively. Accuracy of the MSI value derived from the traditional method was 63.4%. Compared with the traditional method, the proposed semi-automatic method in the current study may provide results with a higher accuracy to differentiate benign and malignant lesions. Therefore, the proposed method should be considered as a supplementary tool for the diagnosis of breast lesions. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the diagnostic efficacy of pharmacokinetic parameters derived from dynamic contrast‑enhanced magnetic resonance imaging (DCE‑MRI) in prospective evaluation of pancreatic neuroendocrine neoplasms (pNENs) grading. A total of 25 histologically proven patients with pNENs (30 lesions in total) who underwent DCE‑MRI were enrolled. Lesions were divided into G1, G2 neuroendocrine tumor (NET) and G3 NET/neuroendocrine carcinoma (NEC) groups based on their histological findings according to 2017 World Health Organization Neuroendocrine Tumor Classification Guideline. In addition, the same numbers of tumor‑free regions were selected using as normal control group. For each group, pharmacokinetic DCE parameters: volume transfer constant (Ktrans); contrast transfer rate constant (kep); extravascular extracellular space volume fraction (ve); and plasma volume fraction (vp) were calculated with Extended Tofts Linear model. Receiver operator characteristics analysis was conducted to assess the diagnostic efficacy of these parameters in pNENs grading. There were significant differences of Ktrans, kep, ve and vp between tumor‑free areas and G1, G2 NET (P<0.001). The Ktrans and kep of G1 NET were significantly lower compared with those of G2 ones (P<0.005). The area under the curve of Ktrans and kep in differentiating G2 from G1 NET were 0.767 and 0.846, respectively. When Ktrans was >0.667 and kep >1.644, the sensitivity of diagnosing G2 NET was the lowest (53.85%), but the specificity was the highest (93.75%). When Ktrans was >0.667 or kep >1.644, the sensitivity of diagnosing G2 NET was 92.31%, but the specificity was 75.00%. Pharmacokinetic parameters of DCE‑MRI, particularly the quantitative values of Ktrans and kep, are helpful for differentiating G2 NET from G1 ones. [ABSTRACT FROM AUTHOR]

A number of studies have demonstrated that dynamic contrast‑enhanced magnetic resonance imaging (DCE‑MRI) may be used to evaluate microvessel density (MVD), and may quantitatively reflect tumor angiogenesis. To investigate the dynamics, including angiogenesis and tumor cellularity, of rabbit VX2 tumors during the 4 weeks following tumor implantation, the present study used DCE‑MRI combined with diffusion‑weighted imaging (DWI) to scan the tumors at 3 days, and then at 1, 2, 3 and 4‑week intervals, following tumor implantation. The dynamics, volume transfer coefficient (Ktrans) and apparent diffusion coefficient (ADC) of the tumor parenchyma were analyzed. Furthermore, the associations between Ktrans and MVD at 4 weeks after tumor implantation were analyzed. Tumor Ktrans was positively correlated with MVD at 4 weeks (r=0.674, P<0.001). Following tumor implantation, the tumor Ktrans level rose for 2 weeks and then began to decline, reaching its lowest point at 4 weeks (P<0.001). ADC values at 1 week were higher than at 3 days, but declined thereafter (P<0.001). Tumor necrosis appeared by 1 week after tumor implantation. The necrosis degree of tumor was gradually increased from the occurrence of necrosis within the 4‑week time span of the present study (1 vs. 2 weeks, P=0.008; 2 vs. 3 weeks, P<0.001; 3 vs. 4 weeks, P<0.001). The present study identified that tumor angiogenesis is a dynamic process that serves a function in tumor growth, and that DCE‑MRI may reflect tumor parenchymal MVD and be useful in evaluating angiogenesis. [ABSTRACT FROM AUTHOR]

The accurate diagnosis of vascular anomalies (VAs) is considered a challenging endeavor. Misdiagnosis of VAs can lead clinicians in the wrong direction, such as the performance of an unnecessary biopsy or inappropriate surgical procedures, which can potentially lead to unforeseen consequences and increase the risk of patient injury. The purpose of the present study was to develop an approach for the diagnosis of VAs of the oral and maxillofacial region based on computed tomography (CT), magnetic resonance imaging (MRI) and dynamic contrast-enhanced MRI (DCE-MRI). In the present study, the CT and MR images of 87 VAs were examined, and the following imaging features were evaluated: Detectability of the lesion, the periphery of the lesion, the inner nature of the lesion, the density of the lesion on CT, the signal intensity of the lesion on MRI, the detectability of phleboliths and the shape of the lesion. A total of 29 lesions were further evaluated using the contrast index (CI) curves created from the DCE-MRI images. A diagnostic diagram, which is based on the imaging features of VAs and CI curve patterns, was subsequently extrapolated. The results obtained demonstrated that the VAs were detected more readily by MRI compared with CT, whereas the detectability of phleboliths was superior when using CT compared with MRI. VAs showed a propensity for homogeneous isodensity on CT, whereas, by contrast, they exhibited a propensity for heterogeneous hyperdensity on CE-CT. VAs also showed a propensity for homogeneous intermediate signal intensity when performing T1-weighted imaging (T1WI), heterogeneous high signal intensity when performing short tau inversion recovery MRI, and heterogeneous high signal intensity when performing fat-saturated CE-T1WI. The CI curves of VAs were found to exhibit a specific pattern: Of the 29 CI curves, 23 (79.3%) showed early weak enhancement, followed by a plateau leading up to 400–600 sec. An imaging-based diagnostic diagram was ultimately formulated. This diagram can act as an aid for radiologists when they are expecting to find a VA, and hopefully serve the purpose of simplifying the diagnostic process. Taken together, the findings of the present study indicated that DCE-MRI may be considered a useful tool for the diagnosis of VAs. [ABSTRACT FROM AUTHOR]

The objective of the present study was to quantitatively analyze the permeability of tumor entity and peritumor edema in glioma grading, using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). In the present retrospective study, 80 patients underwent T1-weighted DCE-MRI examination at 3.0 T and the pathological results (including astrocytoma and oligodendroglioma) were obtained between January 2012 and June 2015. All cases were surgically validated as grade I-IV gliomas. The original DCE-MRI data were analyzed using dual compartment modified Tofts model. The forward volume transfer constant (Ktrans), backflux rate (kep) and fractional volume (ve) were calculated with the region of interest selected on the highest permeability area of the tumor entity and peritumor edema. Analysis of variance with the Bonferroni correction was used to compare the values of Ktrans, kep, and ve of the tumor entity and peritumor edema in different glioma grades. The results of the present study revealed that the Ktrans, kep, and ve values in each stage were associated with the pathological grading (r=0.951, 0.804 and 0.766, respectively). There were significant differences identified between different tumor grades in Ktrans, kep, with the exception being between grades II and III in kep. In addition, there was a significant difference revealed between grade I/II and grade III/IV in ve. Receiver operator characteristics curve analysis was used to evaluate the diagnosis accuracies of permeability parameters. Ktrans was demonstrated to exhibit the highest sensitivity and specificity for evaluating the tumor grade. With the threshold values of 0.160, 0.420 and 0.935 in Ktrans on tumor, glioma grades I vs. II, II vs III and III vs. IV may be differentiated with sensitivities of 0.900, 0.950 and 0.950, and specificities of 0.950, 0.950 and 0.850, respectively. Furthermore, associations were observed between the Ktrans, kep and ve values of peritumor edema and the pathological grading in glioma (Ktrans r=0.438, P<0.001; Kep r=0.385, P<0.001; Ve r=0.397, P<0.001, respectively). Ktrans values in peritumoral edema revealed significant differences between low-grade and high-grade glioma. The sensitivity and specificity for Ktrans of peritumor edema were 0.975 and 0.950, with a threshold value of 0.007. Therefore, the DCE-MRI parameters of Ktrans of tumor entity and peritumor edema in gliomas may be used to accurately differentiate glioma grades. [ABSTRACT FROM AUTHOR]

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a novel imaging modality that can be used to reflect the microcirculation, although its value in diagnosing rectal cancer is unknown. The present study aimed to explore the clinical application of DCE-MRI in the preoperative diagnosis of rectal cancer, and its correlation with tumor differentiation. To achieve this, 40 pathologically confirmed patients with rectal cancer and 15 controls were scanned using DCE-MRI. The Tofts model was applied to obtain the perfusion parameters, including the plasma to extravascular volume transfer (Ktrans), the extravascular to plasma volume transfer (Kep), the extravascular fluid volume (Ve) and the initial area under the enhancement curve (iAUC). Receiver-operating characteristic (ROC) curves were plotted to determine the diagnostic value. The results demonstrated that the time-signal intensity curve of the rectal cancer lesion exhibited an outflow pattern. The Ktrans, Kep, Ve, and iAUC values were higher in the cancer patients compared with controls (P<0.05). The intraclass correlation coefficients of Ktrans, Kep, Ve and iAUC, as measured by two independent radiologists, were 0.991, 0.988, 0.972 and 0.984, respectively (all P<0.001), indicating a good consistency. The areas under the ROC curves for Ktrans and iAUC were both >0.9, resulting in a sensitivity and specificity of 100% and 93.3% for Ktrans, and of 92.5%, and 93.3% or 100%, for iAUC, respectively. In the 40 rectal cancer cases, there was a moderate correlation between Ktrans and iAUC, and pathological differentiation (0.3

The aim of the present study was to investigate the efficacy of dynamic contrast-enhanced magnetic resonance imaging (MRI) in predicting the outcome of using ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation for the treatment of uterine fibroids with T2 hyperintensity under MRI. A total of 131 uterine fibroids from 131 patients that appeared hyperintense under T2-weighted MRI were analyzed. The uterine fibroids were subjectively categorized into slight, irregular or regular enhancement groups, according to pretreatment dynamic contrast-enhanced MRI in the arterial phase within 60 sec after the injection of gadolinium. The non-perfused volume (NPV), which is indicative of successful ablation, was represented as the non-perfused area inside the uterine fibroids on enhanced MRI scans following treatment. Additionally, the treatment duration, treatment efficiency, sonication duration, energy efficiency ratio and any adverse events were recorded. The results indicated that the average NPV ratio for all the treated fibroids was 68.5%, while the average NPV ratios for fibroids with slight, irregular or regular enhancement were 84.7, 70.6 and 57.1%, respectively. Fibroids with regular enhancement were associated with the lowest NPV ratio and the lowest treatment efficiency, but exhibited the highest energy effect ratio and an elevated risk of severe adverse effects. The results of the present study indicate that hyperintense uterine fibroids with slight and irregular enhancement in the arterial phase of dynamic contrast-enhanced MRI are suitable for USgHIFU treatment. By contrast, uterine fibroids with regular enhancement were associated with the lowest treatment efficacy and safety. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the value of quantitative 3-Tesla (3T) magnetic resonance (MR) assessment in the diagnosis of breast lesions. A total of 44 patients with breast lesions were selected. All the patients underwent MR plain scanning and T1 dynamic contrast-enhanced imaging. The vascular function parameters of the lesions, namely volume transfer constant (Ktrans), rate constant (Kep), extravascular extracellular volume fraction (Ve) and integrated area under the curve (iAUC), were acquired. These parameters were compared between benign and malignant breast lesions, and also among differential grades of invasive ductal carcinoma. The values of Ktrans, Kep and iAUC were significantly different between the benign and malignant tumors; however, the values of Ve in the benign and malignant tumors were not significantly different. The values of Ktrans, Kep and iAUC in invasive ductal carcinoma were significantly different between grade I and grade II, and between grade I and grade III; however, there was no significant difference between grade II and grade III. The Ve values in invasive ductal carcinoma did not significantly differ among grades I, II and III. Among the vascular function parameters, Ktrans exhibited the highest sensitivity and specificity in the differentiation of benign and malignant lesions. Quantitative 3-T MR assessment is valuable in the diagnosis of benign and malignant breast lesions. It can also provide reference values for the differentiation of the histological grade of breast invasive ductal carcinoma. [ABSTRACT FROM AUTHOR]

Immune checkpoint inhibitors (ICIs) targeting programmed death ligand-1 (PD-L1) are highly promising therapies for oral squamous cell carcinoma (OSCC). The assessment of PD-L1 expression may help predicting the therapeutic effect of ICIs and, thus, benefit patient selection. Contrast index (CI) parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) have been proven as efficient to assess microvessel density (MVD) in OSCC. The present study aimed to determine the correlation between DCE-MRI parameters and MVD and between DCE-MRI parameters and PD-L1 expression to determine whether DCE-MRI could be used non-invasively to evaluate PD-L1 expression in patients with OSCC. A total of 21 patients with primary OSCC who had undergone a 3T MRI scan, including DCE-MRI, were included in the present study, and CI curve-derived parameters were examined. The MVD and PD-L1 expression in the surgically resected specimens were analyzed using immunohistochemistry (IHC) staining for CD31 and IHC staining for PD-L1, respectively. The results demonstrated that the expression levels of these markers were correlated with DCE-MRI parameters. PD-L1 expression levels were found to be significantly correlated with the maximum CI (CI-max; P=0.007), peak CI (CI-peak; P=0.007), maximum CI gain (CI-gain; P=0.006) and MVD (P=0.001) values. The mean CI-max, CI-peak, CI-gain and MVD values were significantly higher in tumors with high PD-L1 expression (P<0.05). MVD levels were also significantly correlated with the time of CI-max (T-max; P=0.003) and CI-gain (P=0.037). The mean CI-gain was significantly increased, and the mean T-max was significantly shorter in high MVD tumors (P<0.05 and P<0.01, respectively). In summary, the findings from the present study confirmed the correlation between CI parameters, derived from DCE-MRI, and MVD, and suggested that these parameters may be correlated with PD-L1 expression in OSCC tumor cells. [ABSTRACT FROM AUTHOR]

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a novel imaging modality that can be used to reflect the microcirculation, although its value in diagnosing rectal cancer is unknown. The present study aimed to explore the clinical application of DCE-MRI in the preoperative diagnosis of rectal cancer, and its correlation with tumor differentiation. To achieve this, 40 pathologically confirmed patients with rectal cancer and 15 controls were scanned using DCE-MRI. The Tofts model was applied to obtain the perfusion parameters, including the plasma to extravascular volume transfer (Ktrans), the extravascular to plasma volume transfer (Kep), the extravascular fluid volume (Ve) and the initial area under the enhancement curve (iAUC). Receiver-operating characteristic (ROC) curves were plotted to determine the diagnostic value. The results demonstrated that the time-signal intensity curve of the rectal cancer lesion exhibited an outflow pattern. The Ktrans, Kep, Ve, and iAUC values were higher in the cancer patients compared with controls (P<0.05). The intraclass correlation coefficients of Ktrans, Kep, Ve and iAUC, as measured by two independent radiologists, were 0.991, 0.988, 0.972 and 0.984, respectively (all P<0.001), indicating a good consistency. The areas under the ROC curves for Ktrans and iAUC were both >0.9, resulting in a sensitivity and specificity of 100% and 93.3% for Ktrans, and of 92.5%, and 93.3% or 100%, for iAUC, respectively. In the 40 rectal cancer cases, there was a moderate correlation between Ktrans and iAUC, and pathological differentiation (0.3