OBJECTIVE: To compare various models of diffusion-weighted imaging including monoexponential apparent diffusion coefficient (ADC), biexponential (fast diffusion coefficient [Df], slow diffusion coefficient [Ds], and fraction of fast diffusion), stretched-exponential (distributed diffusion coefficient and anomalous exponent term [α]), and kurtosis (mean diffusivity and mean kurtosis [MK]) models in the differentiation of renal solid masses. MATERIALS AND METHODS: A total of 81 patients (56 men and 25 women; mean age, 57 years; age range, 30–69 years) with 18 benign and 63 malignant lesions were imaged using 3T diffusion-weighted MRI. Diffusion model selection was investigated in each lesion using the Akaike information criteria. Mann-Whitney U test and receiver operating characteristic (ROC) analysis were used for statistical evaluations. RESULTS: Goodness-of-fit analysis showed that the stretched-exponential model had the highest voxel percentages in benign and malignant lesions (90.7% and 51.4%, respectively). ADC, Ds, and MK showed significant differences between benign and malignant lesions (p < 0.05) and between low- and high-grade clear cell renal cell carcinoma (ccRCC) (p < 0.05). α was significantly lower in the benign group than in the malignant group (p < 0.05). All diffusion measures showed significant differences between ccRCC and non-ccRCC (p < 0.05) except Df and α (p = 0.143 and 0.112, respectively). α showed the highest diagnostic accuracy in differentiating benign and malignant lesions with an area under the ROC curve of 0.923, but none of the parameters from these advanced models revealed significantly better performance over ADC in discriminating subtypes or grades of renal cell carcinoma (RCC) (p > 0.05). CONCLUSION: Compared with conventional diffusion parameters, α may provide additional information for differentiating benign and malignant renal masses, while ADC remains the most valuable parameter for differentiation of RCC subtypes and for ccRCC grading.
Carcinoma, Renal Cell ; Diffusion ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; ROC Curve

Objective To study the short and long term outcomes in patients after partial hepatectomy carried out for primary hepatocellular carcinoma (PHC) with portal vein tumor thrombosis (PVTF) who were treated with transcatheter arterial chemoembolization (TACE) plus portal vein chemoembolization (PVCE).Methods 57 patients who underwent partial hepatectomy for PHC with PVTT were treated with TACE + PVCE.These patients formed the study group.Another 55 such patients who received TACE only were matched by age and gender to form the control group.Blood samples before and after treatment for these 2 groups were collected to study the serum tumor markers.Any chemotherapy-related toxicity and complications were recorded.The hepatocellular carcinoma recurrence rate and recurrence time were recorded on follow up.Survival analysis was conducted.Results There was no significant difference between the two groups in TACE treatment times (P ＞ 0.05).In the study group,the levels of AFP,IGF-Ⅱ,and IGFBP-2 were significantly lower than those in the control group at 1 month after chemotherapy [respectively,(4.3 ± 0.5) μg/L vs.(4.8±0.6) μg/L,(3.3±0.4) μg/L vs.(4.0±0.5) μg/L,(5.3±0.6) μg/L vs.(5.8 ± 0.6) μg/L;all P ＜ 0.05].The range of follow-up of the patients in this study were 9 to 45 months after operation.The 1 year recurrence rate after operation in the study group was significantly lower than those in the control group (28.1％ vs.47.3％) (P＜0.05).The PFS,OS,2 year and 3 year survival rates were all significantly higher than those in the control group [respectively,(13.4 ± 4.6) m vs.(11.0±3.5) m,(22.6±10.9) m vs.(17.2 ±10.1) m,43.9％ vs.25.5％,33.3％ vs.16.4％].The differences in the PFS and OS between the two groups were significantly different (P ＜ 0.05).There was no significant difference in the rates in toxicity between the two groups (P ＞ 0.05).In the study group,2 patients (3.5％) developed bleeding from esophageal and gastric fundus vein rupture,while there were no such cases in the control group.Conclusion Compared with TACE alone,the combination of PVCE and TACE after partial hepatectomy for patients with PHC with PVTT effectively reduced tumor burden,prevented liver recurrence and improved long-term survival rates,with no significant increase in toxicity and complication rates.

Objective:To evaluate the diagnostic performance of a radiomics model based on dynamic contrast-enhanced MRI (DCE-MRI) and diffusion weighted imaging (DWI) in small breast cancer (≤ 20 mm in greatest dimension), and to compare the results with those of an experienced radiologist’s interpretation.Methods:A total of 205 small breast lesions in 192 consecutive female patients from June 2016 to January 2018 at Renji Hospital, School of Medicine, Shanghai Jiaotong University, were retrospectively enrolled in the study. All lesions (≤ 20 mm in greatest dimension) were confirmed by surgical pathological results. The lesions were divided into a training set (116 lesions) and an independent test set (89 lesions). Based on preoperative breast DCE-MRI and DWI data, a radiomics model was built using gradient boosting decision tree (GBDT). The GBDT model was applied to the test set for differentiation between malignant and benign small breast lesions. Cases of the test set were also evaluated by an experienced radiologist for benign and malignant diseases differentiation. ROC curve was used to assess the diagnostic performance for the GBDT model and the radiologist evaluation, respectively. Differences in the area under the ROC curve (AUC) were analyzed by the DeLong test. Differences in sensitivity, specificity and accuracy were evaluated by the McNemar test. Kappa values were used to assess the agreement between different evaluation methods.Results:The AUC of the GBDT model (0.950) showed no significant difference from that of the radiologist’s evaluation based on DCE-MRI combing DWI data (0.935) ( Z=0.499, P=0.618). However, it showed the AUC of GBDT model was significantly higher than that of evaluation based on DCE-MRI (0.874) or DWI (0.832) alone ( Z=2.024， P=0.043； Z=2.772， P=0.006). The sensitivity, specificity and accuracy of the best cutoff point of GBDT model were 90.0%, 89.8% and 89.9% respectively. The sensitivity, specificity and accuracy of evaluation based on DCE-MRI combined with DWI were 97.5%, 79.6% and 87.6% respectively. There was no significant difference in diagnostic performance between the two methods (χ 2=0.800,2.286 and 0.083, P>0.05). Conclusions:A radiomics model based on DCE-MRI and DWI images provided good diagnostic performance in small breast cancer. The results of radiomics were favorably comparable with those of experienced radiologist evaluation based on the combination of DCE-MRI and DWI data.

Objective To evaluate the relationship between concurrent myocardial bridge at anterior descending branch and the formation of coronary atherosclerosis plaques by using transluminal attenuation gradient (TAG). Methods A total of 198 patients underwent coronary CTA in Renji Hospital of Shanghai Jiaotong University School of Medcine from June 2017 to March 2018 and the results showed the anterior descending myocardial bridge. The data were retrospectively analyzed. All patients completed the coronary CTA with 320?row detector CT. According to the manifestations of myocardial bridge on CTA,the patients were divided into deep and superficial myocardial bridge groups. According to whether the patients were complicated with coronary atherosclerotic plaques, they were divided into isolated myocardial bridge group and myocardial bridge with coronary atherosclerotic plaque group. The thickness and length of myocardial bridge, the volume of coronary atherosclerotic plaques at the site of myocardial bridge, the pre?bridge and post?bridge TAG values, and the K ratio were recorded. Independent sample t test (normal distribution) or Mann?Whitney U test (skewed distribution) was used to compare the difference of measurement data among different groups. χ2 test was used to compare the difference of enumeration data among different groups. Pearson correlation test was used to analyze the correlation among pre?bridge and post?bridge TAG values,K ratio,thickness and length of myocardial bridge and plaque volume. The influence of above indexes on plaque occurrence was analyzed by binary logistic regression analysis. The relationship between main influence indexes and plaque formation was analyzed by receiver operating characteristic curve (ROC). Results Ninety nine patients had isolated myocardial bridge,99 with myocardial bridge and coronary atherosclerotic plaques,27 with superficial myocardial bridge and 171 with deep myocardial bridge. All atherosclerotic plaques occurred in pre?bridge and the mean volume of plaques was (91.6±83.0)mm3. The differences in sex, age, height, body weight and body mass index werenot statistically significant between isolated myocardial bridge group and myocardial bridge with coronary atherosclerotic plaque group (all P>0.05). The difference in pre?bridge TAG value was statistically significant between the isolated myocardial bridge group and myocardial bridge with coronary atherosclerotic plaque group (all P<0.05), but not statistically significant in post?bridge TAG value and K ratio (all P>0.05). The difference in pre?bridge and post?bridge TAG values and K value was not statistically significant between the superficial group and the deep group (all P>0.05). There was a weak negative correlation (r=-0.205,-0.316,-0.339,respectively,P<0.05) between the plaque volume and pre?bridge&post?bridge TAG values and K ratio. The pre?bridge TAG value significantly affected the plaque formation (P=0.014) and the odds ratio was 0.884 (95% CI 0.801 to 0.976). While other factors had no significant effects on plaque formation (all P>0.05). The area under curveof plaque formation promoted by pre?bridge TAG value was 0.582. When the diagnostic critical value was －37.26 HU/mm, the sensitivity and specificity of pre?bridge TAG value in plaque formation were 31.31% and 81.82%, respectively. Conclusion The TAG value of anterior descending bridge is an independent risk factor for plaque occurrence. The abnormal TAG value of anterior descending myocardial bridge can be detected early by CTA.