MRI-derived extracellular volume fraction as a prognostic biomarker for early recurrence after R0 resection of pancreatic ductal adenocarcinoma

Extracellular volume fraction with MRI: As an alternative predictive biomarker to dynamic contrast-enhanced MRI for chemotherapy response of pancreatic ductal adenocarcinoma

The objective of our study was to predict response to chemoradiation therapy in patients with head and neck squamous cell carcinoma (HNSCC) by combined use of diffusion-weighted imaging (DWI) and high-spatial-resolution, high-temporal-resolution dynamic contrast-enhanced MRI (DCE-MRI) parameters from primary tumors and metastatic nodes. Thirty-two patients underwent pretreatment DWI and DCE-MRI using a modified radial imaging sequence. Postprocessing of data included motion-correction algorithms to reduce motion artifacts. The median apparent diffusion coefficient (ADC), volume transfer constant (K(trans)), extracellular extravascular volume fraction (v(e)), and plasma volume fraction (v(p)) were computed from primary tumors and nodal masses. The quality of the DCE-MRI maps was estimated using a threshold median chi-square value of 0.10 or less. Multivariate logistic regression and receiver operating characteristic curve analyses were used to determine the best model to discriminate responders from nonresponders. Acceptable χ(2) values were observed from 84% of primary tumors and 100% of nodal masses. Five patients with unsatisfactory DCE-MRI data were excluded and DCE-MRI data for three patients who died of unrelated causes were censored from analysis. The median follow-up for the remaining patients (n = 24) was 23.72 months. When ADC and DCE-MRI parameters (K(trans), v(e), v(p)) from both primary tumors and nodal masses were incorporated into multivariate logistic regression analyses, a considerably higher discriminative accuracy (area under the curve [AUC] = 0.85) with a sensitivity of 81.3% and specificity of 75% was observed in differentiating responders (n = 16) from nonresponders (n = 8). The combined use of DWI and DCE-MRI parameters from both primary tumors and nodal masses may aid in prediction of response to chemoradiation therapy in patients with HNSCC.

Objective:The aim of this study was to predict response to neoadjuvant chemotherapy (NAC) in patients with locally advanced hypopharyngeal cancer by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).Methods:A retrospective study enrolled 46 diagnosed locally advanced hypopharyngeal cancer. DCE-MRI were performed prior to and after two cycles of NAC. The volume transfer constant (Ktrans), extracellular extravascular volume fraction (Ve), and plasma volume fraction (Kep) were computed from primary tumors. DCE-MRI parameters were used to measure tumor response according to the Response Evaluation Criteria in Solid Tumors criteria (RECIST).Results：After 2 NAC cycles, 30 out of 46 patients were categorized into the responder group, whereas the other 16 were categorized into non-responder group. Compared with the pretreatment value, the post-treatment Ktrans and Kep was significantly lower (P < 0.05), but no significant change in Ve (P > 0.05). Compared with non-responders, a notably higher pretreatment Ktrans, Kep, lower post-treatment Ktrans, higher ΔKtrans and ΔKep were observed in responders (all P < 0.05). While the pretreatment Ve, post-treatment Ve, and ΔVe did not differ significantly (P>0.05) between the two groups. The receiver operating characteristic curve analysis revealed that pretreatment Ktrans of 0.202/min is the most optimal cut-off in predicting response to chemotherapy, resulting in an AUC of 0.837 and corresponding sensitivity and specificity of 76.7%, and 81.1%, respectively.Conclusion:DCE-MRI especially pretreatment Ktrans can potentially predict the treatment response to neoadjuvant chemotherapy for hypopharyngeal cancer.Advances in knowledge:Few studies of DCE-MRI on hypopharyngeal cancer treated with chemoradiation reported. The results demonstrate that DCE-MRI especially pretreatment Ktrans may be more potential value in predicting the treatment response to neoadjuvant chemotherapy for hypopharyngeal cancer.

PurposeThis systematic review aims to assess and summarize the clinical values of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameter changes as early biomarkers of tumor responses following radiation therapy (RT) in patients with spinal metastases.Materials and MethodsA systematic search was conducted on five electronic databases: PubMed, Scopus, Science Direct, Cochrane, and Embase. Studies were included if they mentioned DCE-MRI parameter changes before and after RT in patients with spinal metastases with a correlation to tumor responses based on clinical and imaging criteria. The Quality Assessment of Diagnostic Accuracy Studies 2 was used to assess study quality.ResultsThis systematic review included seven studies involving 107 patients. All seven studies evaluated the transfer constant (Ktrans), six studies evaluated the plasma volume fraction (Vp), three studies evaluated the extravascular extracellular space volume fraction, and two studies evaluated the rate constant. There were variations in the type of primary cancer, RT techniques used, post-treatment scan time, and median follow-up time. Despite the variations, however, the collected evidence generally suggested that significant differences could be detected in DCE-MRI parameters between before and after RT, which might reflect treatment success or failures in long-term follow-up. Responders showed higher reduction and lower values of Ktrans and Vp after RT. DCE-MRI parameters showed changes and detectable recurrences significantly earlier (up to 6 months) than conventional MRI with favorable diagnostic values.ConclusionThe results of this systematic review suggested that DCE-MRI parameter changes in patients with spinal metastases could be a promising tool for treatment-response assessment following RT. Lower values and higher reduction of Ktrans and Vp after treatment demonstrated good prediction of local control. Compared to conventional MRI, DCE-MRI showed more rapid changes and earlier prediction of treatment failure.

Objective To investigate the correlation between quantitative parameters of dynamic contrast-enhanced MRI (DCE-MRI) after neoadjuvant chemotherapy and pathological grades in esophageal squamous cell carcinoma. Methods Fifty-six patients with esophageal squamous cell carcinoma who were confirmed by esophagoscope and received neoadjuvant chemotherapy before operation between September 2015 and December 2017 in the Affiliated Cancer Hospital of Zhengzhou University were prospectively analyzed,and MRI examination was performed within one week before operation. All patients underwent routine chest MRI and DCE-MRI scanning,and quantitative parameters of DCE-MRI,including volume transfer constant (Ktrans),exchange rate constant (Kep) and extravascular extracellular volume fraction (Ve) were measured. Pathological grading was assessed as highly differentiated,moderately differentiated,poorly differentiated,and undifferentiated. Intraclass correlation coefficient (ICC) was calculated from the results of two radiologists. Kruskal-Wallis H test was used to compare the differences of quantitative parameters between different pathological grade groups of DCE-MRI,and Mann-Whitney U test was utilized to compare the intraclass differences among pathological grades. Spearman rank correlation analysis was performed for evaluating the correlation between DCE-MRI parameters and pathological grade of esophageal squamous cell carcinoma. The receiver operating characteristic (ROC) curves were used to evaluate the diagnosis accuracy of different DCE-MRI parameters in pathological grade of esophageal squamous cell carcinoma after neoadjuvant chemotherapy. Results The 56 patients were divided into four groups according to pathological findings:well differentiated group (n=8),moderately differentiated group (n=39),poorly differentiated group (n=9) and undifferentiated group (n=0). The differences of Ktransmean,Ktrans75%,Kepmax,Kepmean,Kep75% between different pathological grading groups were statistically significant (all P<0.05),and these parameters showed positive correlation significantly with pathological grading (r values were 0.778, 0.632, 0.594, 0.725, 0.489 respectively,all P<0.05). The ROC curve area of Ktransmean,Ktrans75% in the diagnosis of pathological grade for esophageal squamous cell carcinoma was 0.750,0.856,respectively. The diagnostic efficiency of Ktrans75% was the best with the diagnostic threshold of 0.693/min,sensitivity of 87.5%,specificity of 78.5%,respectively. Conclusion The quantitative parameters of DCE-MRI after neoadjuvant chemotherapy in esophageal squamous cell carcinoma have the potential value for predicting pathological grade. Key words: Esophageal neoplasms; Magnetic resonance imaging; Pathology

Dynamic contrast-enhanced MRI of gastric cancer: Correlations of the pharmacokinetic parameters with histological type, Lauren classification, and angiogenesis

To investigate the feasibility of dynamic, contrast-enhanced, magnetic resonance imaging (DCE-MRI) for perfusion quantification of gastric cancers, and to correlate the DCE-MRI parameters with the pathological prognostic factors. This prospective study was approved by our Institutional Review Board. Twenty-seven patients with gastric cancers underwent DCE-MRI using a free-breathing, radial, gradient-echo (GRE) sequence with k-space weighted image contrast (KWIC) reconstruction on a 3T scanner. The DCE-MRI parameters (volume transfer coefficient [K(trans) ], reverse reflux rate constant [Kep ], extracellular extravascular volume fraction [Ve ], and initial area under the gadolinium concentration curve during the first 60 seconds [iAUC]) of gastric cancer and normal wall were measured and compared with each other using the Wilcoxon signed rank test. The relationship between the DCE-MRI parameters of gastric cancer and the pathological prognostic factors were evaluated using the Mann-Whitney test or the Spearman rank correlation test. DCE-MRIs were of diagnostic quality in 22 patients (81.5%). Ve and iAUC were significantly higher in gastric cancer than in normal gastric wall (P < 0.05). Ve showed significant positive correlation with T-staging of gastric cancers (P < 0.05). K(trans) was significantly correlated with the grades of epidermal growth-factor receptor expression (P < 0.05). DCE-MRI using a radial GRE with KWIC reconstruction is feasible for quantification of the perfusion dynamics of gastric cancers, and the DCE-MRI parameters of gastric cancers may provide prognostic information.

The prognostic value of dynamic contrast-enhanced MR imaging in patients with glioblastoma is controversial. We investigated the added prognostic value of dynamic contrast-enhanced MR imaging to clinical parameters and molecular biomarkers in patients with glioblastoma by using histogram analysis. This retrospective study consisted of 61 patients who underwent preoperative dynamic contrast-enhanced MR imaging for glioblastoma. The histogram parameters of dynamic contrast-enhanced MR imaging, including volume transfer constant, extravascular extracellular volume fraction, and plasma volume fraction, were calculated from entire enhancing tumors. Univariate analyses for overall survival and progression-free survival were performed with preoperative clinical and dynamic contrast-enhanced MR imaging parameters and postoperative molecular biomarkers. Multivariate Cox regression was performed to build pre- and postoperative models for overall survival and progression-free survival. The performance of models was assessed by calculating the Harrell concordance index. In univariate analysis, patients with higher volume transfer constant and extravascular extracellular volume fraction values showed worse overall survival and progression-free survival, whereas plasma volume fraction showed no significant correlation. In multivariate analyses for overall survival, the fifth percentile value of volume transfer constant and kurtosis of extravascular extracellular volume fraction were independently prognostic in the preoperative model, and kurtosis of volume transfer constant and extravascular extracellular volume fraction were independently prognostic in the postoperative model. For progression-free survival, independent prognostic factors were minimum and fifth percentile values of volume transfer constant and kurtosis of extravascular extracellular volume fraction in the preoperative model and kurtosis of extravascular extracellular volume fraction in the postoperative model. The performance of preoperative models for progression-free survival was significantly improved when minimum or fifth percentile values of volume transfer constant and kurtosis of extravascular extracellular volume fraction were added. Higher volume transfer constant and extravascular extracellular volume fraction values are associated with worse prognosis, and dynamic contrast-enhanced MR imaging may have added prognostic value in combination with preoperative clinical parameters, especially in predicting progression-free survival.

Quantitative dynamic contrast-enhanced MR imaging for the preliminary prediction of the response to gemcitabine-based chemotherapy in advanced pancreatic ductal carcinoma

Objective To analyze the value of dynamic contrast-enhanced MRI(DCE-MRI) parameters of Extended Tofts and Exchange model in the differential diagnosis of hepatocellular carcinoma (HCC) and hepatic metastases of colorectal cancer. Methods A retrospective analysis of 40 pathologically confirmed cases was conducted, including 25 cases of HCC and 15 cases of hepatic metastases of colorectal cancer,all patients underwent DCE-MRI. Applying liver double blood supplement model, and respectively using Extended Tofts two-compartment model and Exchange model liver microvascular permeability parameters [volume transfer constant of the contrast agent(Ktrans), efflux rate from extracellular extravascular space to plasma(Kep), extravascular extracellular volume fraction(Ve)and blood plasma space volume fraction (Vp)] and the perfusion parameter hepatic arterial perfusion index(HPI) in the lesion parenchyma of HCC and metastases were calculated. We used t test to compare the differences of the parameters measured from the two types of tumors, statistically significant parameters between HCC and metastases were screened which compared with the gold standard of pathological findings in order to draw the ROC curves to evaluate the diagnostic efficacy of different model parameters, using χ2 test compared the diagnostic accuracy of optimal parameters between the two models. Results By using Extended Tofts and Exchange model, Ktrans value of HCC were (0.661±0.402)/min and (0.604±0.316)/min respectively, Ktrans value of hepatic metastases were (0.196±0.175)/min and (0.179±0.135)/min respectively; Vp value of HCC were (0.334±0.217) and (0.294±0.098), Vp value of hepatic metastases were (0.089±0.015) and (0.089±0.022),respectively; HPI value of HCC were (0.680±0.281) and (0.769±0.245), HPI value of hepatic metastases were (0.326±0.216), (0.373±0.298), respectively. There were significant differences between HCC and hepatic metastases in Ktrans, Vp and HPI values in both models(P 0.05).Drawn ROC curves of Ktrans, Vp, HPI, the Ktrans value (area under the curve of 0.869) among Extended Tofts model parameters was selected as optimal parameter to identify HCC and hepatic metastases; the HPI value (area under the curve of 0.845) among Exchange model parameters was selected as optimal parameter to differentiate these two types of tumors.The diagnostic accordance rate of Extended Tofts model and Exchange model were 80.0% (32/40) , 82.5% (33/40), respectively; There was no significant difference between them (χ2=0.082, P=0.775). Conclusions Parameters including Ktrans, Vp, HPI of the Extended Tofts model and Exchange model in DCE-MRI perfusion can be used to identify HCC and hepatic metastases of colorectal cancer. Among these parameters, Ktrans of Extended Tofts model and HPI of Exchange model have higher diagnostic value in differentiating HCC and hepatic metastases of colorectal cancer. Key words: Liver neoplasms; Magnetic resonance imaging; Comparative study

Diffuse myocardial fibrosis in adolescents operated with arterial switch for transposition of the great arteries - A CMR study

BACKGROUNDThe activity staging of Crohn’s disease (CD) in the terminal ileum is critical in developing an accurate clinical treatment plan. The activity of terminal ileum CD is associated with the microcirculation of involved bowel walls. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging (DWI) can reflect perfusion and permeability of bowel walls by providing microcirculation information. As such, we hypothesize that DCE-MRI and DWI parameters can assess terminal ileum CD, thereby providing an opportunity to stage CD activity.AIMTo evaluate the value of DCE-MRI and DWI in assessing activity of terminal ileum CD. METHODSForty-eight patients with CD who underwent DCE-MRI and DWI were enrolled. The patients’ activity was graded as remission, mild and moderate-severe. The transfer constant (Ktrans), wash-out constant (Kep), and extravascular extracellular volume fraction (Ve) were calculated from DCE-MRI and the apparent diffusion coefficient (ADC) was obtained from DWI. Magnetic Resonance Index of Activity (MaRIA) was calculated from magnetic resonance enterography. Differences in these quantitative parameters were compared between normal ileal loop (NIL) and inflamed terminal ileum (ITI) and among different activity grades. The correlations between these parameters, MaRIA, the Crohn’s Disease Activity Index (CDAI), and Crohn’s Disease Endoscopic Index of Severity (CDEIS) were examined. Receiver operating characteristic curve analyses were used to determine the diagnostic performance of these parameters in differentiating between CD activity levels.RESULTSHigher Ktrans (0.07 ± 0.04 vs 0.01 ± 0.01), Kep (0.24 ± 0.11 vs 0.15 ± 0.05) and Ve (0.27 ± 0.07 vs 0.08 ± 0.03), but lower ADC (1.41 ± 0.26 vs 2.41 ± 0.30) values were found in ITI than in NIL (all P < 0.001). The Ktrans, Kep, Ve and MaRIA increased with disease activity, whereas the ADC decreased (all P < 0.001). The Ktrans, Kep, Ve and MaRIA showed positive correlations with the CDAI (r = 0.866 for Ktrans, 0.870 for Kep, 0.858 for Ve, 0.890 for MaRIA, all P < 0.001) and CDEIS (r = 0.563 for Ktrans, 0.567 for Kep, 0.571 for Ve, 0.842 for MaRIA, all P < 0.001), while the ADC showed negative correlations with the CDAI (r = -0.857, P < 0.001) and CDEIS (r = -0.536, P < 0.001). The areas under the curve (AUC) for the Ktrans, Kep, Ve, ADC and MaRIA values ranged from 0.68 to 0.91 for differentiating inactive CD (CD remission) from active CD (mild to severe CD). The AUC when combining the Ktrans, Kep and Ve was 0.80, while combining DCE-MRI parameters and ADC values yielded the highest AUC of 0.95.CONCLUSIONDCE-MRI and DWI parameters all serve as measures to stage CD activity. When they are combined, the assessment performance is improved and better than MaRIA.

Can dynamic contrast-enhanced MRI evaluate VEGF expression in brain glioma? An MRI-guided stereotactic biopsy study

Multiparametric MRI for Staging of Bowel Inflammatory Activity in Crohn's Disease with MUSE-IVIM and DCE-MRI: A Preliminary Study

Objective To investigate the value of dynamic contrast-enhanced MRI parameters in the diagnosis of cervical squamous cell carcinoma. Methods A retrospective analysis of dynamic contrast enhanced MRI in 55 patients with pathologically diagnosed cervical squamous cell carcinoma without prior treatment. They were divided into three groups based on grade of differentiation: well differentiated(6 patients),moderately differentiated(28 patients)and poorly differentiated group(21 patients). Capacity volume transfer constant (Ktrans),exchange rate constant(Kep) and extravascular extracellular volume fraction(Ve) were measured in each group of patients, and comparing the correlation with ANOVA, DCE-MRI parameters and grading of squamous differentiation using Spearman rank correlation analysis. Results Ktrans of the poorly, moderately and well differentiated cervical squamous cell carcinoma were (2.42±0.58),(1.71± 0.78),(1.27±0.78)/min respectively, Kep were (4.17±1.23), (3.08±1.58), (2.55±0.87)/min respectively, Ve were 0.60 ± 0.12,0.60 ± 0.19, 0.43 ± 0.17 respectively. Statistical difference of Ktransand Kep were found among the subgroups of different pathological grading.(F values were 7.518 and 4.234,P all 0.05). Statistical difference of Ktransand Kep were seen in multiple comparisons, between the groups of poorly and moderately differentiated groups poorly and well differentiated groups (P all 0.05). There were moderate negative correlation between Ktrans,Kep and the pathological degree (r=-0.531 and-0.446, P=0.001and0.002) , Ve had no correlation between pathological grade (r=-0.220, P = 0.141). Conclusion DCE-MRI parameters Ktrans and Kep reveal perfusion characteristics in different pathological grades of cervical squamous cell carcinoma. Key words: Uterine cervix neoplasms; Magnetic resonance imaging