Objective:To investigate the impact of the interval period between biopsy and MR examination on tumor detection and extraprostatic extension (EPE) assessment for prostate cancer (PCa) using multi-parametric MRI (mpMRI).Methods:The study was cross-sectional and retrospectively included 130 patients with PCa who underwent RP and preoperative systematic biopsies followed by mpMRI between January 2021 and December 2022 in the First Medical Center of Chinese PLA General Hospital. Patients were divided into 3 groups according to interval following biopsy (group A,<3 weeks, 31 cases; group B, 3-6 weeks, 67 cases; group C,>6 weeks, 32 cases). The percentages of hemorrhage volume in the total prostate were drawn on T 1WI and calculated. The junior, senior and expert radiologists independently localized the index lesions and calculated the accuracy for tumor detection, in addition to assessing the probabilities of EPE according to EPE grade. The correlation between the hemorrhage extent and interval was analyzed using the Spearman correlation coefficient. The accuracy for tumor detection was compared using χ2 test among groups. The diagnostic performance of the radiologists for EPE prediction was assessed using the receiver operating characteristic curve, and the differences between the corresponding area under the curve (AUC) were compared using the DeLong test. Results:The percentage of hemorrhage was correlated with the interval between biopsy and MR examination ( r=-0.325, P<0.001). The detection accuracy of junior radiologist was 83.9% (26/31), 76.1% (51/67), and 78.1% (25/32) in group A, B and C, respectively; no differences were observed in the detection accuracy among three groups ( χ2=0.76, P=0.685). The detection accuracy of senior radiologist was 83.9% (26/31), 80.6% (54/67), and 71.9% (23/32) in 3 groups with no differences ( χ2=1.53, P=0.464). The detection accuracy of expert radiologist was 80.6% (25/31), 77.6% (52/67), and 93.8% (30/32) with no differences ( χ2=3.95, P=0.139). The AUC (95% CI) for predicting EPE were 0.830 (0.652-0.940), 0.704 (0.580-0.809), 0.800 (0.621-0.920) in the group A, B and C for junior radiologist; 0.876 (0.708-0.966), 0.768 (0.659-0.863), 0.896 (0.736-0.975) for senior radiologist; and 0.866 (0.695-0.961), 0.813 (0.699-0.895), 0.852 (0.682-0.952) for expert radiologist, respectively. No differences were observed among the subgroups in each radiologist ( P>0.05). Conclusion:The interval period does not significantly affect the detection accuracy and EPE assessment of PCa using mpMRI. There is probably no necessity for prolonged intervals following systematic biopsy to preserve the clarity of MRI interpretation for PCa.

Objective To explore the feasibility of constructing a short-term therapeutic efficacy prediction model for hepatocellular carcinoma(HCC)after radiofrequency ablation(RFA)based on texture analysis of preoperative MRI arterial phase images.Methods A retrospective analysis was conducted on 169 HCC patients treated with RFA.Based on the short-term therapeutic efficacy,the patients were divided into a good prognosis group(112 cases)and a poor prognosis group(57 cases).Texture features of preoperative MRI arterial phase images were extracted using Mazda software,and dimension reduction was performed through Fisher coefficient,mutual information,classification error probability,and mean correlation coefficient.The patients were divided into a training group(n=119)and a testing group(n=50)in a 7∶3 ratio.Independent sample t-tests and the least absolute shrinkage and selection operator(LASSO)algorithm were employed for further feature selection.Subsequently,a radiomics model was established using LASSO regression and evaluated through the receiver operating characteristic(ROC)curve and area under the curve(AUC).Results The radiomics model comprised features such as S_2__2_SumOfSqs,Teta1,S_5_0_DifVarnc,S_2_0_DifEntrp,Horzl_LngREmph,and S_5_5_InvDfMom.The AUC of the model were 0.987[95％confidence interval(CI)0.965-1.000]and 0.918(95％CI 0.818-1.000)in the training and testing groups,respectively.The sensitivity was 98.7％(95％CI 92.4-100)and 93.9％(95％CI 84.8-100),and the specificity was 97.5％(95％CI 90.0-100)and 88.2％(95％CI 70.6-100),respectively.Conclusion The construction of a predictive model for short-term therapeutic efficacy of HCC after RFA based on texture analysis of preoperative MRI arterial phase images is feasible and demonstrates good predictive performance.

Purpose To explore the diagnostic value of prostate imaging report and data system 2.1(PI-RADS v2.1)combined with prostate-specific antigen density(PSAD)for clinically significant prostate cancer(csPCa)in prostate-specific antigen(PSA)gray area(4-10 ng/ml)based on two-center data.Materials and Methods The clinical and imaging data of patients with PSA gray zone prostate disease who underwent multi-parametric magnetic resonance imaging and all pathological data in the First Medical Center(center 1)and the Sixth Medical Center(center 2)of the Chinese PLA General Hospital from January 2017 to May 2022 were retrospectively selected and analyzed.The patients from center 1 were used as the training group(220 cases),and the patients from center 2 were used as the test group(50 cases).Logistic regression was used to determine the independent predictors of csPCa in the training group,and the diagnostic efficacy of multi-parameter combination for csPCa was analyzed,which was further verified in the test group.Results There were significant differences in prostate volume,PSAD and PI-RADS v2.1 scores between the csPCa and non-csPCa groups in the training group(Z=-6.468,6.589,75.676,all P＜0.001).Logistic regression analysis showed that PI-RADS v2.1 score and PSAD were the independent risk factors for csPCa(both P＜0.001).The area under the curve of the Logistic regression model composed of PI-RADS v2.1 and PSAD for predicting csPCa in the PSA gray zone was 0.860(95％CI 0.808-0.903)in the training group and 0.906(95％CI 0.790-0.970)in the test group,respectively.The area under the curve of Logistic regression model was significantly higher than that of PI-RADS v2.1 and PSAD,respectively,with statistically significant difference(both P＜0.05).When the PI-RADS v2.1 score was low or moderate risk and PSAD＜0.15 ng/ml2,csPCa in the training group and the test group was with low detection rate.Conclusion PI-RADS v2.1 score and PSAD may be the independent risk factors for predicting csPCa in the PSA gray zone.The combined application of the two methods is better than the single method in the diagnosis of csPCa in the PSA gray zone,with benefits for clinical biopsy decision-making.

Purpose To explore the additional value of apparent diffusion coefficient(ADC)histogram in predicting extraprostatic extension(EPE)of prostate cancer.Materials and Methods Consecutive patients undergoing multi-parameter MRI and subsequent radical prostatectomy from January 2021 to December 2022 were retrospectively included in this study.Two radiologists independently estimated EPE by using national cancer institute grading system for extraprostatic extension(EPE grade system),with disagreement resolved by discussion.Histogram metrics were derived from three-dimensional volumes of interest encompassing the entire lesion on ADC maps using FireVoxel,obtaining mean ADC,1st,5th,10th,25th,50th,75th,90th,95th and 99th ADC values.The ADC histograms between the groups with and without EPE were compared.Multivariable Logistic regression analysis was used to identify the independent predictive factors of EPE,and a combined model was developed.Receiver operator characteristic curve was used to evaluate the diagnostic performance,and the area under the curve was calculated and compared.Results Thirty-four patients(34％)had pathologic confirmed EPE after radical prostatectomy.ADC histogram parameters showed significant differences between patients with and without EPE(P＜0.05).Multivariate Logistic regression analysis revealed 99th ADC(OR=0.609,P=0.008)and EPE grade system(OR=4.158,P＜0.001)were independent predictors of EPE.For predicting EPE,the area under the curve of 99th ADC,EPE grade system and the combined model were 0.756,0.805 and 0.856,respectively.The area under the curve of 99th ADC and the EPE grade system in identifying EPE showed no significant difference.The diagnostic efficacy of combined model was significantly superior to that of 99th ADC or EPE grading system(Z=2.223,2.208,both P＜0.05).Conclusion The ADC histogram parameters demonstrate additional value for preoperative prediction of EPE.Combining the 99th ADC histogram parameter with the EPE grade system may improve the diagnostic efficacy of EPE.

Objective:To explore the value of intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) parameters in different regions of the kidney in distinguishing IgA nephropathy (IgAN) patients from healthy volunteers.Methods:This study was a cross-sectional study. Eighty-four patients diagnosed with IgAN (IgAN group) who underwent renal biopsy (lower pole of the left kidney) and were pathologically confirmed at the First Medical Center of PLA General Hospital from February 2022 to September 2023 and thirty-four healthy volunteers (control group) were included prospectively. The regions of interest were outlined in the right renal cortex, medulla, and parenchyma for all subjects, and the apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudo-diffusion coefficient (D *), and perfusion fraction (f) were measured in the corresponding regions. The differences in IVIM-DWI parameters between the IgAN group and the control group were compared using the student′s t-test or the Mann-Whitney U test. Receiver operating characteristic curve analysis was performed on the parameters with statistically significant differences, and the area under the curve (AUC) was calculated. Results:There were statistically significant differences in renal cortical ADC, renal parenchymal ADC, renal cortical D, renal parenchymal D, and renal medullary f values between the IgAN group and the control group ( Z=-3.03, -2.21, -2.62, -2.03, -2.03; P=0.002, 0.027, 0.009, 0.043, 0.042). The AUCs (95% CI) for diagnosing IgAN using renal cortical ADC, renal parenchymal ADC, renal cortical D, renal parenchymal D, and renal medullary f values were 0.679 (0.586-0.762), 0.630 (0.537-0.717), 0.654 (0.535-0.774), 0.619 (0.497-0.742), and 0.620 (0.495-0.745), respectively. There were no statistically significant differences in renal medullary ADC, D, renal cortex, medulla and parenchyma D *, renal cortical and renal parenchymal f values between the two groups ( P>0.05). Conclusion:The quantitative parameters of renal IVIM-DWI are influenced by different measurement regions, among which the ADC, D of renal cortex and parenchyma, and f of renal medulla can be used for the initial diagnosis of IgAN.

Objective:To evaluate the calf muscle cross-sectional area (CSA) and fat fraction (FF) in amateur marathon runners based on T 2WI-Flex fat-suppression sequence and iterative decomposition of water and fat with echo asymmetrical and least-squares estimation quantitation sequence (IDEAL-IQ) technique, and to explore the correlation between them and age, body mass index (BMI), running age, speed exercise, and monthly exercise. Methods:From September to November 2022, 37 amateur marathon group (marathon group) and 12 healthy volunteers (control group) who did not often exercise were recruited in Shijiazhuang. T 2WI-Flex fat-suppression sequence and IDEAL-IQ sequence were performed on all subjects. The anterior group of the right calf (tibialis anterior, extensor hallucis longus, extensor digital longus), external group of the calf (peroneus longus, peroneus brevis), soleus, medial head and lateral head of the gastrocnemius were delineated along the edge of the muscle contour as regions of interest, and the CSA and FF values of the muscles were obtained. Twelve subjects matched with the clinical data of the control group were selected from the marathon group (marathon matched group), and the differences in CSA and FF were compared by independent sample t test or Mann-Whitney U test. Spearman correlation analysis was used to evaluate the correlation between CSA and FF values of the right calf and running-related indicators including age, BMI, running age, speed exercise, and monthly exercise in 37 amateur marathon runners. Results:The CSA of the right calf soleus muscle in the marathon matched matched group was larger than that in the control group ( t=-2.09, P=0.048). There was no significant difference in CSA of other calf muscles between the two groups ( P>0.05). The FF values of the right calf anterior group, the outer group, the soleus muscle, the medial head and the lateral head of the gastrocnemius muscle in the marathon matched group were lower than those in the control group ( P<0.05). The BMI of 37 amateur marathon runners was positively correlated with the CSA and FF values of the anterior group, the outer group, the soleus, the medial head and the lateral head of the gastrocnemius muscle (CSA: r=0.628, 0.468, 0.680, 0.566, 0.615, respectively, all P<0.05; FF value: r=0.395, 0.567, 0.631, 0.482, 0.516, respectively, all P<0.05). The FF values of the anterior group, the outer group, the soleus, the medial head and the lateral head of the gastrocnemius muscle were negatively correlated with monthly exercise ( r=-0.337, -0.405, -0.437, -0.338, -0.446, respectively, all P<0.05). Conclusions:Long-term running training can reduce the FF value of each calf muscle group, and the FF value of calf muscles is negatively correlated with the amount of running each month. Long-term running training has the greatest effect on the CSA of soleus muscle.

With the advancement of surgical techniques, the 5-year survival rate of colorectal cancer has significantly improved. However, incomplete lymph node dissection during operation leads to local recurrence and distant metastasis of the tumor, which has seriously affected the prognosis of patients. In the era of laparoscopy, surgeons' sense of touch is limited, making it difficult to feel and distinguish lymph node metastasis and the location of early colorectal cancer with their hands. The emergence of carbon nanoparticle suspension can help surgeons accurately locate tumors and clean lymph nodes under laparoscopy. This article reviews the clinical application of carbon nanoparticles in lymph node tracing and tumor location in colorectal cancer.

Objective:To explore the value of quantitative parameters of enhanced MRI in predicting the establishment of inferior vena cava collateral circulation in patients with renal cell carcinoma and inferior vena cava tumor thrombus.Methods:Sixty-seven patients with renal cell carcinoma and inferior vena cava tumor thrombus who underwent radical resection and inferior vena cava venography in First Medical Center, PLA General Hospital from May 2006 to January 2021 were included retrospectively. According to the results of inferior vena cava venography, the patients were divided into two groups: the well-established collateral circulation group ( n=41) and the poor-established collateral circulation group ( n=26). Quantitative parameters were measured on preoperative enhanced MRI images, including tumor size, the maximum diameter of bilateral lumbar veins, the length of tumor thrombus, and the long and short diameters of tumor thrombus. Student′s t test or Mann-Whitney U test was used for comparison between the two groups. The independent risk factors related to the establishment of collateral circulation were obtained by binary logistic regression analysis and the model was established. The receiver operating characteristic curve was employed to evaluate MRI quantitative parameters and the logistic model, and the area under the curve (AUC) was compared by the DeLong test. Results:Between the well-established collateral circulation group and the poor-established collateral circulation group, the maximum diameter of the right lumbar vein, the maximum diameter of the left lumbar vein, the length of the tumor thrombus, the long diameter of the tumor thrombus, and the short diameter of the tumor thrombus were different significantly ( P<0.05). There was no significant difference in the tumor size between the two groups ( t=0.30, P=0.766). The AUC of the maximum diameters of the right lumbar veins and left lumbar veins, length of tumor thrombus, long and short diameters of tumor thrombus in predicting the collateral circulation were 0.917 (95%CI 0.824-0.971), 0.869 (95%CI 0.764-0.939), 0.756 (95%CI 0.636-0.853), 0.886 (95%CI 0.785-0.951), and 0.906 (95%CI 0.809-0.963). The AUC of the maximum diameter of the right lumbar vein and the short diameter of the tumor thrombus were larger than those of the length of the tumor thrombus, and the differences were statistically significant ( Z=2.25, 2.04, P=0.025, 0.041), but the AUC between other parameters had no significant difference ( P>0.05). The maximum diameter of the right lumbar vein (OR 24.210, 95%CI 2.845-205.998), the maximum diameter of the left lumbar vein (OR 20.973, 95%CI 2.359-186.490), and the length of the tumor thrombus (OR 23.006, 95%CI 2.952-179.309) were independent risk factors for predicting the establishment of inferior vena cava collateral circulation. The AUC of logistic model was 0.969 (95%CI 0.931-1.000). Conclusion:Quantitative parameters of tumor thrombus and lumbar vein based on enhanced MRI have a good ability in predicting the establishment of inferior vena cava collateral circulation in patients with renal cell carcinoma and inferior vena cava tumor thrombus. The maximum diameter of bilateral lumbar veins and the length of the tumor thrombus were independent risk factors for inferior vena cava collateral circulation.

Objectives:To investigate the effect of fat suppression (FS) T 2WI on the interobserver agreement and diagnostic performance of clear cell likelihood score version 2.0 (ccLS v2.0) for clear cell renal cell carcinoma (ccRCC). Methods:In this retrospective study, the MR images of 111 patients with pathologically confirmed small renal masses (SRM) from January to December 2021 were analyzed in the First Medical Centre, Chinese PLA General Hospital. Of the 111 SRM, 82 cases were ccRCC and 29 cases were non-ccRCC. Two radiologists independently assessed ccLS scores based on T 2WI signal intensity (hypointense, isointense, hyperintense) and other MRI features (ccLS-T 2WI). After a one-month interval, the ccLS scores were independently evaluated utilizing the frequency-selective saturation FS-T 2WI and other MRI features (ccLS-FS-T 2WI). Fisher′s exact test was used to compare the difference in SRM signal intensity on T 2WI and FS-T 2WI. The weighted Kappa test was performed to assess the interobserver agreement of the two radiologists, and differences in the weighted Kappa coefficients were compared using the Gwet consistency coefficient. Receiver operating characteristic curves were drawn to evaluate the diagnostic performance of ccLS-T 2WI and ccLS-FS-T 2WI in diagnosing ccRCC, and the area under the curve (AUC) was compared utilizing the DeLong test. Results:The signal intensity of 111 SRM on T 2WI and FS-T 2WI had statistically significant difference (χ 2=126.33, P<0.001), consistent in 88 cases (79.3%) and varied in 23 cases (20.7%). The weighted Kappa coefficient of ccLS-T 2WI was 0.57 (95%CI 0.45-0.69) between the two radiologists, and the weighted Kappa coefficient of ccLS-FS-T 2WI was 0.55 (95%CI 0.42-0.67), and the difference was not statistically significant ( t=-0.65, P=0.520). The AUC of ccLS-T 2WI for ccRCC diagnosis was 0.92 (95%CI 0.86-0.97), while the AUC of ccLS-FS-T 2WI for ccRCC diagnosis was 0.91 (95%CI 0.85-0.96), and the difference was not statistically significant ( Z=1.50, P=0.133). Conclusions:The interobserver agreement and diagnostic performance of ccLS v2.0 based on T 2WI and FS-T 2WI sequences for ccRCC are comparable, and FS-T 2WI is applicable for the clinical application of ccLS v2.0.

Objective:To investigate the clinical and MRI features of the mixed epithelial and stromal tumor family (MESTF) of the kidney.Methods:From January 2009 to September 2021, 42 patients with pathologically-proven MESTF from the First Medical Center of Chinese PLA General Hospital were collected in this retrospective study. Clinical information, MRI features, and pathological results were documented. According to the Bosniak classification (BC) version 2019, all MESTFs were divided into cystic MESTFs (36 cases) and solid-cystic MESTFs (6 cases). The R.E.N.A.L. nephrometry score (RNS), lesion size, laterality, location, margin, shape, growth pattern, presence of protruding into renal sinus, hemorrhage, and enhancement pattern were evaluated and documented. Based on BC versions 2005 and 2019, all the cystic MESTFs were assessed and divided into low (Ⅰ, Ⅱ, ⅡF) and high (Ⅲ, Ⅳ) grades. The independent sample t test or Mann-Whitney U test were performed to compare age, RNS, and lesion size between cystic MESTFs and solid-cystic MESTFs. Pearson χ 2 test, continuity-adjusted χ 2 test or Fisher exact probability test were utilized to evaluated the differences of clinical and MRI features and the distribution of low or high grades in two versions of BC. Results:Forty-two MESTFs were unilateral and solitary masses, 25 males and 17 females, with a mean age of (41±13) years old. Compared to solid-cystic MESTFs, cystic MESTFs were prone to demonstrate endophytic growth pattern (χ 2=17.77, P<0.001), and no significant differences in other clinical and MRI features were observed between cystic and solid-cystic MESTFs (all P>0.05). There were 7 low-grade and 29 high-grade tumors in the BC version 2005, respectively. Meanwhile, 24 low-grade and 12 high-grade tumors in the BC version 2019, respectively. The distribution of low or high-grade tumors in the two versions of BC had a statistically significant difference (χ 2=16.37, P<0.001). Conclusion:MESTFs demonstrated middle-age onset and no gender predilection. Cystic MESTFs are more likely to exhibit endophytic growth pattern with low-grade classification in BC system version 2019.