Clinical and CT Quantitative Features for Predicting Liver Metastases in Patients with Pancreatic Neuroendocrine Tumors: A Study with Prospective/External Validation

RATIONALE AND OBJECTIVES

We aimed to evaluate clinical characteristics and quantitative CT imaging features for the prediction of liver metastases (LMs) in patients with pancreatic neuroendocrine tumors (PNETs).

METHODS

Patients diagnosed with pathologically confirmed PNETs were included, 133 patients were in the training group, 22 patients in the prospective internal validation group, and 28 patients in the external validation group. Clinical information and quantitative features were collected. The independent variables for predicting LMs were confirmed through the implementation of univariate and multivariate logistic analyses. The diagnostic performance was evaluated by conducting receiver operating characteristic curves for predicting LMs in the training and validation groups.

RESULTS

PNETs with LMs demonstrated significantly larger diameter and lower arterial/portal tumor-parenchymal enhancement ratio, arterial/portal absolute enhancement value (AAE/PAE value) (p < 0.05). After multivariate analyses, A high level of tumor marker (odds ratio (OR): 5.32; 95% CI, 1.54-18.35), maximum diameter larger than 24.6 mm (OR: 7.46; 95% CI, 1.70-32.72), and AAE value ≤ 51 HU (OR: 4.99; 95% CI, 0.93-26.95) were independent positive predictors of LMs in patients with PNETs, with area under curve (AUC) of 0.852 (95%CI, 0.781-0.907). The AUCs for prospective internal and external validation groups were 0.883 (95% CI, 0.686-0.977) and 0.789 (95% CI, 0.602-0.916), respectively.

CONCLUSION

Tumor marker, maximum diameter and absolute enhancement value in arterial phase were independent predictors with good predictive performance for the prediction of LMs in patients with PNETs. Combining clinical and quantitative features may facilitate the attainment of good predictive precision in predicting LMs.

Machine Learning Methods Based on CT Features Differentiate G1/G2 From G3 Pancreatic Neuroendocrine Tumors

RATIONALE AND OBJECTIVES

To identify CT features for distinguishing grade 1 (G1)/grade 2 (G2) from grade 3 (G3) pancreatic neuroendocrine tumors (PNETs) using different machine learning (ML) methods.

MATERIALS AND METHODS

A total of 147 patients with 155 lesions confirmed by pathology were retrospectively included. Clinical-demographic and radiological CT features was collected. The entire cohort was separated into training and validation groups at a 7:3 ratio. Least absolute shrinkage and selection operator (LASSO) algorithm and principal component analysis (PCA) were used to select features. Three ML methods, namely logistic regression (LR), support vector machine (SVM), and K-nearest neighbor (KNN) were used to build a differential model. Receiver operating characteristic (ROC) curves and precision-recall curves for each ML method were generated. The area under the curve (AUC), accuracy rate, sensitivity, and specificity were calculated.

RESULTS

G3 PNETs were more likely to present with invasive behaviors and lower enhancement than G1/G2 PNETs. The LR classifier yielded the highest AUC of 0.964 (95% confidence interval [CI]: 0.930, 0.972), with 95.4% accuracy rate, 95.7% sensitivity, and 92.9% specificity, followed by SVM (AUC: 0.957) and KNN (AUC: 0.893) in the training group. In the validation group, the SVM classier reached the highest AUC of 0.952 (95% CI: 0.860, 0.981), with 91.5% accuracy rate, 97.3% sensitivity, and 70% specificity, followed by LR (AUC: 0.949) and KNN (AUC: 0.923).

CONCLUSIONS

The LR and SVM classifiers had the best performance in the training group and validation group, respectively. ML method could be helpful in differentiating between G1/G2 and G3 PNETs.

Duodenal neuroendocrine neoplasms on enhanced CT: establishing a diagnostic model with duodenal gastrointestinal stromal tumors in the non-ampullary area and analyzing the value of predicting prognosis

OBJECTIVE

To identify CT features and establish a diagnostic model for distinguishing non-ampullary duodenal neuroendocrine neoplasms (dNENs) from non-ampullary duodenal gastrointestinal stromal tumors (dGISTs) and to analyze overall survival outcomes of all dNENs patients.

MATERIALS AND METHODS

This retrospective study included 98 patients with pathologically confirmed dNENs (n = 44) and dGISTs (n = 54). Clinical data and CT characteristics were collected. Univariate analyses and binary logistic regression analyses were performed to identify independent factors and establish a diagnostic model between non-ampullary dNENs (n = 22) and dGISTs (n = 54). The ROC curve was created to determine diagnostic ability. Cox proportional hazards models were created and Kaplan-Meier survival analyses were performed for survival analysis of dNENs (n = 44).

RESULTS

Three CT features were identified as independent predictors of non-ampullary dNENs, including intraluminal growth pattern (OR 0.450; 95% CI 0.206-0.983), absence of intratumoral vessels (OR 0.207; 95% CI 0.053-0.807) and unenhanced lesion > 40.76 HU (OR 5.720; 95% CI 1.575-20.774). The AUC was 0.866 (95% CI 0.765-0.968), with a sensitivity of 90.91% (95% CI 70.8-98.9%), specificity of 77.78% (95% CI 64.4-88.0%), and total accuracy rate of 81.58%. Lymph node metastases (HR: 21.60), obstructive biliary and/or pancreatic duct dilation (HR: 5.82) and portal lesion enhancement ≤ 99.79 HU (HR: 3.02) were independent prognostic factors related to poor outcomes.

CONCLUSION

We established a diagnostic model to differentiate non-ampullary dNENs from dGISTs. Besides, we found that imaging features on enhanced CT can predict OS of patients with dNENs.

A CT-based nomogram established for differentiating gastrointestinal heterotopic pancreas from gastrointestinal stromal tumor: compared with a machine-learning model

OBJECTIVE

To identify CT features and establish a nomogram, compared with a machine learning-based model for distinguishing gastrointestinal heterotopic pancreas (HP) from gastrointestinal stromal tumor (GIST).

MATERIALS AND METHODS

This retrospective study included 148 patients with pathologically confirmed HP (n = 48) and GIST (n = 100) in the stomach or small intestine that were less than 3 cm in size. Clinical information and CT characteristics were collected. A nomogram on account of lasso regression and multivariate logistic regression, and a RandomForest (RF) model based on significant variables in univariate analyses were established. Receiver operating characteristic (ROC) curve, mean area under the curve (AUC), calibration curve and decision curve analysis (DCA) were carried out to evaluate and compare the diagnostic ability of models.

RESULTS

The nomogram identified five CT features as independent predictors of HP diagnosis: age, location, LD/SD ratio, duct-like structure, and HU lesion/pancreas A. Five features were included in RF model and ranked according to their relevance to the differential diagnosis: LD/SD ratio, HU lesion/pancreas A, location, peritumoral hypodensity line and age. The nomogram and RF model yielded AUC of 0.951 (95% CI: 0.842-0.993) and 0.894 (95% CI: 0.766-0.966), respectively. The DeLong test found no statistically significant difference in diagnostic performance (p > 0.05), but DCA revealed that the nomogram surpassed the RF model in clinical usefulness.

CONCLUSION

Two diagnostic prediction models based on a nomogram as well as RF method were reliable and easy-to-use for distinguishing between HP and GIST, which might also assist treatment planning.

Compare image quality of T2-weighted imaging with different phase acceleration factors

Previous studies demonstrated that adjusting the phase acceleration (PA) factors could influence image quality. To improve image quality and decrease respiratory artifacts of lesions in the liver on T2-weighted image by adjusting PA factor and number of excitation (NEX). Sixty consecutive patients with hepatic lesions were enrolled in this prospective research between May 2020 and June 2020. All patients had 3.0T magnetic resonance imaging with 4 sequences (combining PA factors and NEXs, the former was 2 and 3, the latter were 1.5 and 2, respectively, with the same other scanning parameters). Two readers used 5-point quality scales to assess image quality. The signal intensity was measured by drawing regions of interest in the liver, spleen, and background on the T2-weighted imaging. Artifacts, overall image impression, and vascular conspicuity were better when the PA factor was 3 than 2. Artifacts and vascular conspicuity were better when NEX was 2 than 1.5. PA factor 3 and NEX 2 got a higher score in 5-point quality scales and less scan time than the other 3 sequences. Meanwhile, the signal-to-noise ratio of PA factor 3 and NEX 2 was best among these 4 sequences. PA factor and NEX could influence the imaging quality and lesion-to-hepatic contrast in detecting hepatic lesions on T2-weighted images. PA factor 3 and NEX 2 may have a positive effect in the clinic, especially for those with irregular respiration, as it decreased artifacts and reduced scan time.

Recent Advances in Well-Designed Therapeutic Nanosystems for the Pancreatic Ductal Adenocarcinoma Treatment Dilemma

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant tumor with an extremely poor prognosis and low survival rate. Due to its inconspicuous symptoms, PDAC is difficult to diagnose early. Most patients are diagnosed in the middle and late stages, losing the opportunity for surgery. Chemotherapy is the main treatment in clinical practice and improves the survival of patients to some extent. However, the improved prognosis is associated with higher side effects, and the overall prognosis is far from satisfactory. In addition to resistance to chemotherapy, PDAC is significantly resistant to targeted therapy and immunotherapy. The failure of multiple treatment modalities indicates great dilemmas in treating PDAC, including high molecular heterogeneity, high drug resistance, an immunosuppressive microenvironment, and a dense matrix. Nanomedicine shows great potential to overcome the therapeutic barriers of PDAC. Through the careful design and rational modification of nanomaterials, multifunctional intelligent nanosystems can be obtained. These nanosystems can adapt to the environment's needs and compensate for conventional treatments' shortcomings. This review is focused on recent advances in the use of well-designed nanosystems in different therapeutic modalities to overcome the PDAC treatment dilemma, including a variety of novel therapeutic modalities. Finally, these nanosystems' bottlenecks in treating PDAC and the prospect of future clinical translation are briefly discussed.

A nomogram diagnostic prediction model of pancreatic metastases of small cell lung carcinoma based on clinical characteristics, radiological features and biomarkers

Objective

To investigate clinical characteristics, radiological features and biomarkers of pancreatic metastases of small cell lung carcinoma (PM-SCLC), and establish a convenient nomogram diagnostic predictive model to differentiate PM-SCLC from pancreatic ductal adenocarcinomas (PDAC) preoperatively.

Methods

A total of 299 patients with meeting the criteria (PM-SCLC n=93; PDAC n=206) from January 2016 to March 2022 were retrospectively analyzed, including 249 patients from hospital 1 (training/internal validation cohort) and 50 patients from hospital 2 (external validation cohort). We searched for meaningful clinical characteristics, radiological features and biomarkers and determined the predictors through multivariable logistic regression analysis. Three models: clinical model, CT imaging model, and combined model, were developed for the diagnosis and prediction of PM-SCLC. Nomogram was constructed based on independent predictors. The receiver operating curve was undertaken to estimate the discrimination.

Results

Six independent predictors for PM-SCLC diagnosis in multivariate logistic regression analysis, including clinical symptoms, CA199, tumor size, parenchymal atrophy, vascular involvement and enhancement type. The nomogram diagnostic predictive model based on these six independent predictors showed the best performance, achieved the AUCs of the training cohort (n = 174), internal validation cohort (n = 75) and external validation cohort (n = 50) were 0.950 (95%CI, 0.917-0.976), 0.928 (95%CI, 0.873-0.971) and 0.976 (95%CI, 0.944-1.00) respectively. The model achieved 94.50% sensitivity, 83.20% specificity, 86.80% accuracy in the training cohort and 100.00% sensitivity, 80.40% specificity, 86.70% accuracy in the internal validation cohort and 100.00% sensitivity, 88.90% specificity, 87.50% accuracy in the external validation cohort.

Conclusion

We proposed a noninvasive and convenient nomogram diagnostic predictive model based on clinical characteristics, radiological features and biomarkers to preoperatively differentiate PM-SCLC from PDAC.

KRAS mutation status between left- and right-sided colorectal cancer: are there any differences in computed tomography?

PURPOSE

To investigate the differences in clinicopathological and imaging features according to KRAS mutation status in left- and right-sided colorectal cancer.

METHOD

A total of 157 patients with pathologically proven colorectal cancer and preoperative contrast-enhanced multidetector CT examinations were enrolled. According to the tumor location and KRAS status, they were divided into two groups: the left-sided colorectal cancer (LCC) group (wild type, mutant type) and the right-sided colorectal cancer (RCC) group (wild type, mutant type). Clinicopathological and imaging features were recorded in each group. The imaging observation indicators included short axis diameter (SAD), longitudinal tumor length (LTL), tumor shape, pericolic fat stranding, bowel stenosis, intratumoral low-density range, enhancement pattern, and bowel obstruction. Univariate and multivariate logistic regression analyses were performed to compare the difference in KRAS mutation status between groups.

RESULTS

In the LCC group, SAD, tumor shape, degree of pericolic fat stranding, and bowel obstruction were significant indicators for predicting KRAS status (P < 0.05). In the RCC group, CA19-9, SAD, and intratumoral low-density range were significant indicators for predicting KRAS status (P < 0.05.). The area under the curve (AUC) of the combination image indicators in the LCC group was 0.802 [cutoff point 0.372, 95% confidence interval (CI) 0.718-0.888, sensitivity 85.4%, specificity 72.0%]. The AUC in the RCC group was 0.828 (cutoff point 0.647, 95% CI 0.726-0.931, sensitivity 79.5%, specificity 75.0%).

CONCLUSION

The CT imaging features associated with KRAS mutation status in the LCC and RCC groups were different. The combination of tumor location and imaging features can help to further improve the predictive value of KRAS status.

Extracellular matrix modulating enzyme functionalized biomimetic Au nanoplatform-mediated enhanced tumor penetration and synergistic antitumor therapy for pancreatic cancer

BACKGROUND

Excessive extracellular matrix (ECM) deposition in pancreatic ductal adenocarcinoma (PDAC) severely limits therapeutic drug penetration into tumors and is associated with poor prognosis. Collagen is the most abundant matrix protein in the tumor ECM, which is the main obstacle that severely hinders the diffusion of chemotherapeutic drugs or nanomedicines.

METHODS

We designed a collagenase-functionalized biomimetic drug-loaded Au nanoplatform that combined ECM degradation, active targeting, immune evasion, near-infrared (NIR) light-triggered drug release, and synergistic antitumor therapy and diagnosis into one nanoplatform. PDAC tumor cell membranes were extracted and coated onto doxorubicin (Dox)-loaded Au nanocages, and then collagenase was added to functionalize the cell membrane through lipid insertion. We evaluated the physicochemical properties, in vitro and in vivo targeting, penetration and therapeutic efficacy of the nanoplatform.

RESULTS

Upon intravenous injection, this nanoplatform efficiently targeted the tumor through the homologous targeting properties of the coated cell membrane. During penetration into the tumor tissue, the dense ECM in the PDAC tissues was gradually degraded by collagenase, leading to a looser ECM structure and deep penetration within the tumor parenchyma. Under NIR irradiation, both photothermal and photodynamic effects were produced and the encapsulated chemotherapeutic drugs were released effectively, exerting a strong synergistic antitumor effect. Moreover, this nanoplatform has X-ray attenuation properties that could serve to guide and monitor treatment by CT imaging.

CONCLUSION

This work presented a unique and facile yet effective strategy to modulate ECM components in PDAC, enhance tumor penetration and tumor-killing effects and provide therapeutic guidance and monitoring.

Building contrast-enhanced CT-based models for preoperatively predicting malignant potential and Ki67 expression of small intestine gastrointestinal stromal tumors (GISTs)

PURPOSE

To assess contrast-enhanced computed tomography (CE-CT) features for predicting malignant potential and Ki67 in small intestinal gastrointestinal stromal tumors (GISTs) and the correlation between them.

METHODS

We retrospectively analyzed the pathological and imaging data for 123 patients (55 male/68 female, mean age: 57.2 years) with a histopathological diagnosis of small intestine GISTs who received CE-CT followed by curative surgery from May 2009 to August 2019. According to postoperatively pathological and immunohistochemical results, patients were categorized by malignant potential and the Ki67 index, respectively. CT features were analyzed to be associated with malignant potential or the Ki67 index using univariate analysis, logistic regression and receiver operating curve analysis. Then, we explored the correlation between the Ki67 index and malignant potential by using the Spearman rank correlation.

RESULTS

Based on univariate and multivariate analysis, a predictive model of malignant potential of small intestine GISTs, consisting of tumor size (p < 0.001) and presence of necrosis (p = 0.033), was developed with the area under the receiver operating curve (AUC) of 0.965 (95% CI, 0.915-0.990; p < 0.001), with 91.53% sensitivity, 96.87% specificity, 96.43% PPV, 92.54% NPV, 94.31% diagnostic accuracy. For high Ki67 expression, a model made up of tumor size (p = 0.051), presence of ulceration (p = 0.054) and metastasis (p = 0.001) may be the best predictive combination with an AUC of 0.785 (95% CI, 0.702-0.854; p < 0.001), 63.33% sensitivity, 76.34% specificity, 46.34% PPV, 86.59% NPV, 73.17% diagnostic accuracy. Ki67 index showed a moderate positive correlation with mitotic count (r = 0.578, p < 0.001), a weak positive correlation with tumor size (r = 0.339, p < 0.001) and with risk stratification (r = 0.364, p < 0.001).

CONCLUSION

Features on CE-CT could preoperatively predict malignant potential and high Ki67 expression of small intestine GISTs, and Ki67 index may be a promising prognostic factor in predicting the prognosis of small intestine GISTs, independent of the risk stratification system.

Ultra-thin layered double hydroxide-mediated photothermal therapy combine with asynchronous blockade of PD-L1 and NR2F6 inhibit hepatocellular carcinoma

Background

The efficacy of immune checkpoint blockade (ICB), in the treatment of hepatocellular carcinoma (HCC), is limited due to low levels of tumor-infiltrating T lymphocytes and deficient checkpoint blockade in this immunologically "cool" tumor. Thus, combination approaches are needed to increase the response rates of ICB and induce synergistic antitumor immunity.

Methods

Herein, we designed a pH-sensitive multifunctional nanoplatform based on layered double hydroxides (LDHs) loaded with siRNA to block the intracellular immune checkpoint NR2F6, together with the asynchronous blockade surface receptor PD-L1 to induce strong synergistic antitumor immunity. Moreover, photothermal therapy (PTT) generated by LDHs after laser irradiation modified an immunologically “cold” microenvironment to potentiate Nr2f6-siRNA and anti-PD-L1 immunotherapy. Flow cytometry was performed to assess the immune responses initiated by the multifunctional nanoplatform.

Results

Under the slightly acidic tumor extracellular environment, PEG detached and the re-exposed positively charged LDHs enhanced tumor accumulation and cell uptake. The accumulated siRNA suppressed the signal of dual protumor activity in both immune and H22 tumor cells by silencing the NR2F6 gene, which further reduced the tumor burden and enhanced systemic antitumor immunity. The responses include enhanced tumor infiltration by CD4⁺ helper T cells, CD8⁺ cytotoxic T cells, and mature dendritic cells; the significantly decreased level of immune suppressed regulator T cells. The therapeutic responses were also attributed to the production of IL-2, IFN-γ, and TNF-α. The prepared nanoparticles also exhibited potential magnetic resonance imaging (MRI) ability, which could serve to guide synergistic immunotherapy treatment.

Conclusions

In summary, the three combinations of PTT, NR2F6 gene ablation and anti-PD-L1 can promote a synergistic immune response to inhibit the progression of primary HCC tumors and prevent metastasis. This study can be considered a proof-of-concept for the targeting of surface and intracellular immune checkpoints to supplement the existing HCC immunotherapy treatments.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01565-9.

Quantitative analysis of enhanced CT in differentiating well-differentiated pancreatic neuroendocrine tumors and poorly differentiated neuroendocrine carcinomas

OBJECTIVE

To identify quantitative CT features for distinguishing well-differentiated pancreatic neuroendocrine tumors (PNETs) from poorly differentiated pancreatic neuroendocrine carcinomas (PNECs).

MATERIALS AND METHODS

Seventeen patients with PNECs and 131 patients with PNETs confirmed by biopsy or surgery were retrospectively included. General demographic (sex, age) and CT quantitative parameters (arterial/portal absolute enhancement, arterial/portal relative enhancement ratio, arterial/portal enhancement ratio) were collected. Univariate and multivariate logistic regression analyses were performed to confirm independent variables for differentiating PNECs from PNETs. Receiver operating characteristic (ROC) curves for each quantitative parameter were generated to determine their diagnostic ability.

RESULTS

PNECs had a much lower mean arterial/portal absolute enhancement value (19.5 ± 11.0 vs. 78.8 ± 47.2; 28.1 ± 15.8 vs. 77.0 ± 39.4), arterial/portal relative enhancement ratio (0.57 ± 0.36 vs. 2.03 ± 1.31; 0.80 ± 0.52 vs. 1.99 ± 1.13), and arterial/portal enhancement ratio (0.62 ± 0.27 vs. 1.22 ± 0.49; 0.74 ± 0.19 vs. 1.21 ± 0.36) than PNETs (all p < 0.001). After multivariable analysis, arterial absolute enhancement (odds ratio [OR]: 0.96, 95% confidence interval [CI]: 0.93, 0.99) and portal absolute enhancement (OR: 0.96, 95% CI: 0.92, 0.99) were independent factors for differentiating PNECs from PNETs. For each quantitative parameter, arterial lesion enhancement yielded the highest diagnostic performance, with an area under the curve (AUC) of 0.922 (95% CI: 0.867-0.960), followed by portal absolute enhancement.

CONCLUSIONS

Arterial/portal absolute enhancements were independent predictors with good diagnostic accuracy for differentiating between PNETs and PNECs. Quantitative parameters of enhanced CT can distinguish PNECs from PNETs.

KEY POINTS

• PNECs were hypovascular and had a much lower enhanced CT attenuation in both arterial and portal phases than well-differentiated PNETs. • Quantitative parameters derived from enhanced CT can be used to distinguish PNECs from PNETs. • Arterial absolute enhancement and portal absolute enhancement were independent predictive factors for differentiating between PNETs and PNECs.

Machine Learning-Based Radiological Features and Diagnostic Predictive Model of Xanthogranulomatous Cholecystitis

Background

Xanthogranulomatous cholecystitis (XGC) is a rare benign chronic inflammatory disease of the gallbladder that is sometimes indistinguishable from gallbladder cancer (GBC), thereby affecting the decision of the choice of treatment. Thus, this study aimed to analyse the radiological characteristics of XGC and GBC to establish a diagnostic prediction model for differential diagnosis and clinical decision-making.

Methods

We investigated radiological characteristics confirmed by the RandomForest and Logistic regression to establish computed tomography (CT), magnetic resonance imaging (MRI), CT/MRI models and diagnostic prediction model, and performed receiver operating characteristic curve (ROC) analysis to prove the effectiveness of the diagnostic prediction model.

Results

Based on the optimal features confirmed by the RandomForest method, the mean area under the curve (AUC) of the ROC of the CT and MRI models was 0.817 (mean accuracy = 0.837) and 0.839 (mean accuracy = 0.842), respectively, whereas the CT/MRI model had a considerable predictive performance with the mean AUC of 0.897 (mean accuracy = 0.906). The diagnostic prediction model established for the convenience of clinical application was similar to the CT/MRI model with the mean AUC and accuracy of 0.888 and 0.898, respectively, indicating a preferable diagnostic efficiency in distinguishing XGC from GBC.

Conclusions

The diagnostic prediction model showed good diagnostic accuracy for the preoperative discrimination of XGC and GBC, which might aid in clinical decision-making.

A radiologic diagnostic scoring model based on CT features for differentiating gastric schwannoma from gastric gastrointestinal stromal tumors

We aimed to further explore the CT features of gastric schwannoma (GS), propose and validate a convenient diagnostic scoring system to distinguish GS from gastric gastrointestinal stromal tumors (GISTs) preoperatively. 170 patients with submucosal tumors pathologically confirmed (GS n=35; gastric GISTs n=135) from Hospital 1 were analyzed retrospectively as the training cohort, and 72 patients (GS=11; gastric GISTs=61) from Hospital 2 were enrolled as the validation cohort. We searched for significant CT imaging characteristics and constructed the scoring system via binary logistic regression and converted regression coefficients to weighted scores. The ROC curves, AUCs and calibration tests were carried out to evaluate the scoring models in both the training cohort and the validation cohort. For convenient assessment, the system was further divided into four score ranges and their diagnostic probability of GS was calculated respectively. Four CT imaging characteristics were ultimately enrolled in this scoring system, including transverse position (2 points), location (5 points), perilesional lymph nodes (6 points) and pattern of enhancement (2 points). The AUC of the scoring model in the training cohort were 0.873 (95% CI, 0.816-0.929) and the cutoff point was 6 points. In the validation cohort, the AUC was 0.898 (95% CI, 0.804-0.957) and the cutoff value was 5 points. Four score ranges were as follows: 0-3 points for very low probability of GS, 4-7 points for low probability; 8-9 points for middle probability; 10-15 points for very high probability. A convenient scoring model to preoperatively discriminate GS from gastric GISTs was finally proposed.

Pancreatic Serous Cystic Neoplasms and Mucinous Cystic Neoplasms: Differential Diagnosis by Combining Imaging Features and Enhanced CT Texture Analysis

Objective

To establish a diagnostic model by combining imaging features with enhanced CT texture analysis to differentiate pancreatic serous cystadenomas (SCNs) from pancreatic mucinous cystadenomas (MCNs).

Materials and Methods

Fifty-seven and 43 patients with pathology-confirmed SCNs and MCNs, respectively, from one center were analyzed and divided into a training cohort (n = 72) and an internal validation cohort (n = 28). An external validation cohort (n = 28) from another center was allocated. Demographic and radiological information were collected. The least absolute shrinkage and selection operator (LASSO) and recursive feature elimination linear support vector machine (RFE_LinearSVC) were implemented to select significant features. Multivariable logistic regression algorithms were conducted for model construction. Receiver operating characteristic (ROC) curves for the models were evaluated, and their prediction efficiency was quantified by the area under the curve (AUC), 95% confidence interval (95% CI), sensitivity and specificity.

Results

Following multivariable logistic regression analysis, the AUC was 0.932 and 0.887, the sensitivity was 87.5% and 90%, and the specificity was 82.4% and 84.6% with the training and validation cohorts, respectively, for the model combining radiological features and CT texture features. For the model based on radiological features alone, the AUC was 0.84 and 0.91, the sensitivity was 75% and 66.7%, and the specificity was 82.4% and 77% with the training and validation cohorts, respectively.

Conclusion

This study showed that a logistic model combining radiological features and CT texture features is more effective in distinguishing SCNs from MCNs of the pancreas than a model based on radiological features alone.

Self-amplification of oxidative stress with tumour microenvironment-activatable iron-doped nanoplatform for targeting hepatocellular carcinoma synergistic cascade therapy and diagnosis

BACKGROUND

Hepatocellular carcinoma is insensitive to many chemotherapeutic agents. Ferroptosis is a form of programmed cell death with a Fenton reaction mechanism. It converts endogenous hydrogen peroxide into highly toxic hydroxyl radicals, which inhibit hepatocellular carcinoma progression.

METHODS

The morphology, elemental composition, and tumour microenvironment responses of various organic/inorganic nanoplatforms were characterised by different analytical methods. Their in vivo and in vitro tumour-targeting efficacy and imaging capability were analysed by magnetic resonance imaging. Confocal microscopy, flow cytometry, and western blotting were used to investigate the therapeutic efficacy and mechanisms of complementary ferroptosis/apoptosis mediated by the nanoplatforms.

RESULTS

The nanoplatform consisted of a silica shell doped with iron and disulphide bonds and an etched core loaded with doxorubicin that generates hydrogen peroxide in situ and enhances ferroptosis. It relied upon transferrin for targeted drug delivery and could be activated by the tumour microenvironment. Glutathione-responsive biodegradability could operate synergistically with the therapeutic interaction between doxorubicin and iron and induce tumour cell death through complementary ferroptosis and apoptosis. The nanoplatform also has a superparamagnetic framework that could serve to guide and monitor treatment under T2-weighted magnetic resonance imaging.

CONCLUSION

This rationally designed nanoplatform is expected to integrate cancer diagnosis, treatment, and monitoring and provide a novel clinical antitumour therapeutic strategy.

Diagnostic Value of CT- and MRI-Based Texture Analysis and Imaging Findings for Grading Cartilaginous Tumors in Long Bones

Objective

To confirm the diagnostic performance of computed tomography (CT)-based texture analysis (CTTA) and magnetic resonance imaging (MRI)-based texture analysis for grading cartilaginous tumors in long bones and to compare these findings to radiological features.

Materials and Methods

Twenty-nine patients with enchondromas, 20 with low-grade chondrosarcomas and 16 with high-grade chondrosarcomas were included retrospectively. Clinical and radiological information and 9 histogram features extracted from CT, T1WI, and T2WI were evaluated. Binary logistic regression analysis was performed to determine predictive factors for grading cartilaginous tumors and to establish diagnostic models. Another 26 patients were included to validate each model. Receiver operating characteristic (ROC) curves were generated, and accuracy rate, sensitivity, specificity and positive/negative predictive values (PPV/NPV) were calculated.

Results

On imaging, endosteal scalloping, cortical destruction and calcification shape were predictive for grading cartilaginous tumors. For texture analysis, variance, mean, perc.01%, perc.10%, perc.99% and kurtosis were extracted after multivariate analysis. To differentiate benign cartilaginous tumors from low-grade chondrosarcomas, the imaging features model reached the highest accuracy rate (83.7%) and AUC (0.841), with a sensitivity of 75% and specificity of 93.1%. The CTTA feature model best distinguished low-grade and high-grade chondrosarcomas, with accuracies of 71.9%, and 80% in the training and validation groups, respectively; T1-TA and T2-TA could not distinguish them well. We found that the imaging feature model best differentiated benign and malignant cartilaginous tumors, with an accuracy rate of 89.2%, followed by the T1-TA feature model (80.4%).

Conclusions

The imaging feature model and CTTA- or MRI-based texture analysis have the potential to differentiate cartilaginous tumors in long bones by grade. MRI-based texture analysis failed to grade chondrosarcomas.

A Non-Invasive Scoring System to Differential Diagnosis of Clear Cell Renal Cell Carcinoma (ccRCC) From Renal Angiomyolipoma Without Visible Fat (RAML-wvf) Based on CT Features

Background

Renal angiomyolipoma without visible fat (RAML-wvf) and clear cell renal cell carcinoma (ccRCC) have many overlapping features on imaging, which poses a challenge to radiologists. This study aimed to create a scoring system to distinguish ccRCC from RAML-wvf using computed tomography imaging.

Methods

A total of 202 patients from 2011 to 2019 that were confirmed by pathology with ccRCC (n=123) or RAML (n=79) were retrospectively analyzed by dividing them randomly into a training cohort (n=142) and a validation cohort (n=60). A model was established using logistic regression and weighted to be a scoring system. ROC, AUC, cut-off point, and calibration analyses were performed. The scoring system was divided into three ranges for convenience in clinical evaluations, and the diagnostic probability of ccRCC was calculated.

Results

Four independent risk factors are included in the system: 1) presence of a pseudocapsule, 2) a heterogeneous tumor parenchyma in pre-enhancement scanning, 3) a non-high CT attenuation in pre-enhancement scanning, and 4) a heterogeneous enhancement in CMP. The prediction accuracy had an ROC of 0.978 (95% CI, 0.956–0.999; P=0.011), similar to the primary model (ROC, 0.977; 95% CI, 0.954–1.000; P=0.012). A sensitivity of 91.4% and a specificity of 93.9% were achieved using 4.5 points as the cutoff value. Validation showed a good result (ROC, 0.922; 95% CI, 0.854–0.991, P=0.035). The number of patients with ccRCC in the three ranges (0 to <2 points; 2–4 points; >4 to ≤11 points) significantly increased with increasing scores.

Conclusion

This scoring system is convenient for distinguishing between ccRCC and RAML-wvf using four computed tomography features.

Imaging features of myopericytoma arising from the parotid gland: Report of 2 cases and literature review

RATIONALE

Myopericytoma of the parotid gland is a rare condition of which preoperative definitive diagnosis is relatively challenging. The purpose of this case report is to highlight the radiologic features of myopericytoma of parotid gland.

PATIENT CONCERNS

A 62-year-old man presented with a history of a walnut-size mass in left parotid gland when yawned for half-month, and a 48-year-old woman complaint about a grape-size, painless mass behind the right ear for a month.

DIAGNOSES

Radiological examinations suggested that both lesions were cyst-solid mixed lesions with relatively smoothed margins, with or without significant enhancement while the lesion without enhancement had a hemorrhage. Then a diagnosis of benign tumor arising from the parotid gland was made. Final diagnosis of myopericytoma was confirmed by histopathological and immunohistochemical examinations after surgical resection.

INTERVENTIONS

Both patients underwent excision of the tumor and the superficial parotidectomy with facial nerve preservation.

OUTCOMES

Both patients recovered without any intraoperative or postoperative complication and had no signs of recurrence during a 17-month and 5-year follow-up.

LESSONS

Parotid gland myopericytoma is an exceedingly rare tumor which diagnosis can be challenging, and this is the first published report specifying the magnetic resonance features of the disease.

Radiographic Features and Clinical Factor for Preoperative Prediction in the Bulging Duodenal Papilla With Malignancy

Background

To investigate characteristic clinical and imaging features and establish a scoring system for preoperative prediction of malignancy in the bulging duodenal papilla.

Methods

A total of 147 patients with bulging duodenal papilla (Benign enlargement n = 67; malignant enlargement n = 80) from our hospital between 2010 and 2020 were retrospectively analyzed. We investigated meaningful clinical and CT imaging features and established the score model through logistic regression and weighted. The calibration test, the ROC, AUC, and cut-off points were performed in score model. The model was also divided into three score ranges for convenient clinical evaluation.

Results

Three clinical and CT imaging features were finally included in the score model including direct bilirubin (DBil) increase >7 umol/L (3 points), pancreatic duct (PD) dilation >5 mm (2 points), and irregular shape (2 points). The AUCs of the primary predictive model and score model were 0.896 (95% CI, 0.835-0.940) and 0.896 (95% CI, 0.835-0.940), respectively. This scoring system presented with a sensitivity of 78.8% and a specificity of 88.1% when using 2.5 points as cutoff value. Three score ranges were also proposed for convenient clinical use as follows: 0-2 points; 3-4 points; 5-7 points. The number of patients with malignant duodenal papillary enlargement increased with the increasing scores.

Conclusions

We proposed a convenient scoring system to preoperative predict malignancy in the bulging duodenal papilla.

Primary cystic and solid neuroendocrine tumor of the retroperitoneum: A case report

RATIONALE

Primary neuroendocrine tumors (NETs) of the retroperitoneum are extremely rare. The purpose of this case report is to highlight the unusual growth pattern and radiologic features of primary retroperitoneal NETs.

PATIENT CONCERNS

A 46-year-old woman was found to have a retroperitoneal cystic and solid mass during a physical checkup.

DIAGNOSES

The mass was mainly multiseptated in the cystic portion and had a bead-like, lobulated appearance. The solid portion showed restricted diffusion on diffusion-weighted imaging and obvious homogeneous enhancement. The cystic portion showed ring-like and septal enhancement. The patient was diagnosed with a grade 2 (G2) NET of the retroperitoneum after surgery.

INTERVENTIONS

The patient underwent resection of the large retroperitoneal tumor.

OUTCOMES

The patient returned 20 months later with tumor recurrence in the retroperitoneum. She was enrolled in a clinical trial for sulfatinib, and the mass was considerably reduced in size after 4 months. During a nearly 1.5-year follow-up, the mass gradually became slightly enlarged. The expression of somatostatin receptor 2 (SSTR2) was detected, and somatuline was administered as the current treatment.

LESSONS SUBSECTIONS

When a retroperitoneal mass presents as a well-defined cystic or solid hypervascular mass with a fibrous capsule, a primary retroperitoneal NET should be considered in the differential diagnosis.

MR imaging features and a redefinition of the classification system for nodular fasciitis

To analyze magnetic resonance imaging features of nodular fasciitis and redefine the system for classifying this class of lesions.Twenty-seven patients with nodular fasciitis and 71 patients with other soft tissue lesions who underwent surgery or biopsy were retrospectively analysed. Demographic information, medical history, and magnetic resonance imaging features were collected. Classification of nodular fasciitis was performed based on a redefined system. Comparison between 2 groups was performed with Chi-square or Fisher exact test.For nodular fasciitis, the longest average lesion diameter was 1.87 cm (range, 0.52-5.46 cm), and 40.7% of lesions were located in the upper extremities, while 29.6% were located in the head and neck. Compared with skeletal muscle, most lesions exhibited isointensity on T1-weighted imaging and hyperintensity on T2-weighted imaging, and 45.5% of the lesions exhibited rim enhancement, 40.9% showed obvious homogenous enhancement, while 13.6% showed no enhancement or slight enhancement. The subcutaneous type accounted for 25.9% of cases, the fascial type 25.9%, the intramuscular type 29.6%, and the unclassified type 18.5%. The "fascia tail sign" was more frequently observed in nodular fasciitis than in other soft tissue lesions (P < .001). Nodular fasciitis was slightly more likely to present with the "inverted target sign" and "solar halo sign" than other soft tissue lesions (P > .05). The "cloud sign" only appeared in nodular fasciitis (P < .05).The "fascia tail sign" and "cloud sign" could help differentiate nodular fasciitis from other soft tissue lesions. A new classification may improve understanding about nodular fasciitis.

A scoring model for radiologic diagnosis of gastric leiomyomas (GLMs) with contrast-enhanced computed tomography (CE-CT): Differential diagnosis from gastrointestinal stromal tumors (GISTs)

OBJECTIVES

To investigate CT findings and develop a diagnostic score model to differentiate GLMs from GISTs.

METHODS

This retrospective study included 109 patients with pathologically confirmed GLMs (n = 46) and GISTs (n = 63) from January 2013 to August 2018 who received CE-CT before surgery. Demographic and radiological features was collected, including lesion location, contour, presence or absence of intralesional necrosis and ulceration, growth pattern, whether the tumor involved EGJ, the long diameter (LD) /the short diameter (SD) ratio, pattern and degree of lesion enhancement. Univariate analyses and multivariate logistic regression analyses were performed to identify independent predictors and establish a predictive model. Independent predictors for GLMs were weighted with scores based on regression coefficients. A receiver operating characteristic (ROC) curve was created to determine the diagnostic ability of the model. Overall score distribution was divided into four groups to show differentiating probability of GLMs from GISTs.

RESULTS

Five CT features were the independent predictors for GLMs diagnosis in multivariate logistic regression analysis, including esophagogastric junction (EGJ) involvement (OR, 367.9; 95 % CI, 5.8-23302.8; P =  0.005), absence of necrosis (OR, 11.9; 95 % CI, 1.0-138. 1; P =  0.048) and ulceration (OR, 151.9; 95 % CI, 1.4-16899.6; P =  0.037), degree of enhancement (OR, 9.3; 95 % CI, 3.2-27.4; P <  0.001), and long diameter/ short diameter (LD/SD) ratio (OR,170.9; 95 % CI, 8.4-3493.4; P =  0.001). At a cutoff of 9 points, AUC for this score model was 0.95, with 95.65 % sensitivity, 79.37 % specificity, 77.19 % PPV, 96.15 % NPV and 86.24 % diagnostic accuracy. An increasing trend was showed in diagnostic probability of GLMs among four groups based on the score (P <  0.001).

CONCLUSIONS

The newly designed scoring system is reliable and easy-to-use for GLMs diagnosis by distinguishing from GISTs, including EGJ involvement, absence of ulceration and necrosis, mild enhancement and high LD/SD ratio. The overall score of model ranged from 1 to 17 points, which was divided into 4 groups: 1-7 points, 7-10 points, 10-13 points and 13-17 points, with a diagnostic probability of GLMs 0%, 45 %, 83 % and 100 %, respectively.

Novel recyclable deep eutectic solvent boost biomass pretreatment for enzymatic hydrolysis

Deep eutectic solvent (DES) with protonic acid shows the great potential for biomass valorization. However, the acid corrosion and recycling are still severe challenges in biorefinery. Herein, a novel DES by coordinating FeCl₃ in choline chloride/glycerol DES was designed for effective and recyclable pretreatment. As compared to DESs with FeCl₂, ZnCl₂, AlCl₃ and CuCl₂, DES with FeCl₃ approvingly retained most of cellulose in pretreated Hybrid Pennisetum (95.2%). Meanwhile, the cellulose saccharification significantly increased to 99.5%, which was six-fold higher than that of raw biomass. The excellent pretreatment performance was mainly attributed to the high removal of lignin (78.88 wt%) and hemicelluloses (93.63 wt%) under the synergistic effect of Lewis acid and proper hydrogen-bond interaction of DES with FeCl₃. Furthermore, almost all cellulose still can be converted into glucose after five recycling process. Overall, the process demonstrated designed pretreatment was great potential for the low-cost biorefinery and boost the biofuel development.

Contrast-enhanced CT imaging for the assessment of lymph node status in patients with colorectal cancer

The aim of the present study was to identify a novel strategy that predicts the metastatic status of lymph nodes (LNs) in patients diagnosed with colorectal cancer, using detailed characteristics of contrast-enhanced CT scan images. A total of 284 preoperative CT scans derived from patients diagnosed with colorectal cancer at Second Affiliated Hospital, Zhejiang University School of Medicine between January 2013 and July 2018 were retrospectively reviewed. A total of 794 LNs were assessed for size, margins, morphology and subtle internal enhancements in the equilibrium phase. Imaging features were analyzed by two abdominal radiologists (Department of Radiology, Second Affiliated Hospital, Zhejiang University School of Medicine and Departments of Radiology; Shaoxing Second Hospital Departments of Radiology, Shaoxing Second Hospital) in a blind manner. If the conclusions were not concordant, the final score was determined by a senior radiologist who specialized in abdominal radiology for ≥30 years. According to the histopathology results, 27.3% (217/794) of LNs were metastatic (LN+). In addition, LNs >10 mm in size demonstrated sensitivity, specificity, positive predictive values (PPVs) and negative predictive values (NPVs) of 47.0, 80.9, 48.1 and 80.2%, respectively [odds ratio (OR), 3.77; 95% confidence interval (CI), 2.69–5.28]. LNs in the shape of a kidney bean (middle fat depression like kidney) and/or those with an oblong shape were more likely to be metastasis negative LNs (LN-), while lobulated and irregular LNs were more likely to be LN+. In magnified images, internal enhancement characteristics of LN- were defined as homogeneous, spotted, striped and core enhancing. By contrast, rim and heterogeneity enhancement features for LN+ demonstrated sensitivity, specificity, PPVs and NPVs of 46.5, 89.9, 63.5 and 81.7%, respectively (OR, 7.79; 95% CI, 5.33–11.40). The results demonstrated that the internal enhancement features of LNs may be used as a predictor of metastasis. The detailed benign characteristics, such as homogeneity, spotted, striped and core enhancement of LNs may facilitate the identification of LN- in patients with colorectal cancer.

The prognostic value of multidetector CT features in predicting overall survival outcomes in patients with pancreatic neuroendocrine tumors

PURPOSE

To assess the prognostic value of multidetector CT in predicting overall survival outcomes in patients with pancreatic neuroendocrine tumors (PNETs).

METHOD

Seventy-one patients pathologically diagnosed with PNETs were retrospectively included. The clinical and imaging information was evaluated by two radiologists. The difference between well-differentiated and poorly differentiated PNETs was analyzed. Cox proportional hazards models were created to determine the risk factors for overall survival. Kaplan-Meier survival analyses with log-rank tests were used among different subgroups of patients with PNETs.

RESULTS

In the whole cohort, the median survival was 36 months, and the 5-year survival rate was 84.8 %. Patients with poorly differentiated PNETs were more likely to present with symptoms, abnormal tumor markers, larger diameters, irregular shapes, ill-defined margins, invasion into nearby tissues, liver and lymph node metastases, and lower enhancement ratio than those with well-differentiated PNETs (P < 0.05). In the multivariate analysis, lymph node metastases (hazard ratio: 21.52, P = 0.009) and a portal enhancement ratio less than 1.02 (hazard ratio: 30.89, P = 0.024) were significant factors for overall survival. Overall survival decreased with an ill-defined margin, irregular shape, poor differentiation, grade 3 disease, nonfunctional status, abnormal tumor marker levels, invasion into nearby tissues, lymph node and liver metastases, and lower enhancement ratio (log-rank P < 0.05).

CONCLUSIONS

Poorly differentiated PNETs were more aggressiveness than well-differentiated PNETs. Lymph node metastases and a portal enhancement ratio < 1.02 were independent prognostic factors for worse overall survival outcomes in patients with PNETs.

Reduced field-of-view diffusion-weighted imaging (DWI) in patients with gastric cancer: Comparison with conventional DWI techniques at 3.0T: A preliminary study

To evaluate the qualitative image quality and quantitative apparent diffusion coefficient (ADC) value of reduced field-of view (rFOV) and full field-of-view (fFOV) diffusion-weighted imaging (DWI) sequences at 3.0 T in patients with gastric cancer.Fifty-three patients (37 males, 16 females; mean age, 63.3 ± 10.3 years) with 60 lesions with gastric cancer who underwent magnetic resonance (MR) scans, including both rFOV-DWI and fFOV-DWI, were retrospectively analyzed. Two observers subjectively evaluated image quality for both the fFOV-DWI and rFOV-DWI sequences regarding the anatomic details, distortion, lesion conspicuity, artifacts, and overall image quality. The mean ADC values of gastric cancer were calculated. The Wilcoxon test and paired samples t test were used. Interobserver agreement was assessed using kappa statistics.The mean scores based on the 2 observers demonstrated significant differences in image quality in terms of anatomic details, distortion, lesion conspicuity, artifacts and overall image quality at both b values between rFOV-DWI and fFOV-DWI (P < .05) in the whole gastric area. rFOV-DWI yielded significantly better scores in image quality at b = 800 seconds/mm (P < .05) in patients with esophagogastric junction cancers, but there were no significant differences in the gastric corpus and gastric antrum region. The mean tumor ADC values of rFOV-DWI were significantly lower than those of fFOV-DWI (1.237 ± 0.228 × 10-3 mm/second vs 1.683 ± 0.322 × 10-3 mm/second, P < .001).rFOV-DWI yielded significantly better image quality (anatomic details, distortion, lesion conspicuity, artifacts, overall image quality) and more accurate ADC measurements than fFOV-DWI did.

Development of a Novel Multiparametric MRI Radiomic Nomogram for Preoperative Evaluation of Early Recurrence in Resectable Pancreatic Cancer

Background

In pancreatic cancer, methods to predict early recurrence (ER) and identify patients at increased risk of relapse are urgently required.

Purpose

To develop a radiomic nomogram based on MR radiomics to stratify patients preoperatively and potentially improve clinical practice.

Study Type

Retrospective.

Population

We enrolled 303 patients from two medical centers. Patients with a disease‐free survival ≤12 months were assigned as the ER group (n = 130). Patients from the first medical center were divided into a training cohort (n = 123) and an internal validation cohort (n = 54). Patients from the second medical center were used as the external independent validation cohort (n = 126).

Field Strength/Sequence

3.0T axial T₁‐weighted (T₁‐w), T₂‐weighted (T₂‐w), contrast‐enhanced T₁‐weighted (CET₁‐w).

Assessment

ER was confirmed via imaging studies as MRI or CT. Risk factors, including clinical stage, CA19‐9, and radiomic‐related features of ER were assessed. In addition, to determine the intra‐ and interobserver reproducibility of radiomic features extraction, the intra‐ and interclass correlation coefficients (ICC) were calculated.

Statistical Tests

The area under the receiver‐operator characteristic (ROC) curve (AUC) was used to evaluate the predictive accuracy of the radiomic signature in both the training and test groups. The results of decision curve analysis (DCA) indicated that the radiomic nomogram achieved the most net benefit.

Results

The AUC values of ER evaluation for the radiomics signature were 0.80 (training cohort), 0.81 (internal validation cohort), and 0.78 (external validation cohort). Multivariate logistic analysis identified the radiomic signature, CA19‐9 level, and clinical stage as independent parameters of ER. A radiomic nomogram was then developed incorporating the CA19‐9 level and clinical stage. The AUC values for ER risk evaluation using the radiomic nomogram were 0.87 (training cohort), 0.88 (internal validation cohort), and 0.85 (external validation cohort).

Data Conclusion

The radiomic nomogram can effectively evaluate ER risks in patients with resectable pancreatic cancer preoperatively, which could potentially improve treatment strategies and facilitate personalized therapy in pancreatic cancer.

Level of Evidence: 4

Technical Efficacy: Stage 4

J. Magn. Reson. Imaging 2020;52:231–245.

A prognostic nomogram in patients with distant metastasis of pancreatic neuroendocrine tumors: a population-based study

Aim: Prognostic factors in patients with distant metastatic pancreatic neuroendocrine tumors (PNETs) remain uncertain. The purpose of our study is to establish a nomogram to predict survival outcomes in patients with metastatic PNETs. Methods: A total of 878 patients diagnosed with PNETs in the Surveillance, Epidemiology and End Results database between 2004 and 2016 were retrospectively identified. The Kaplan-Meier survival analysis with log-rank test was used to analyze survival outcomes. The nomogram was established after a univariate and multivariate Cox analysis. Results: The independent prognostic variables, including age, tumor grade and primary site surgery were applied to develop a nomogram. The original concordance index was 0.773 (95% CI: 0.751-0.795), and the bias-corrected concordance index was 0.769 (95% CI: 0.748-0.791). The internal calibration curves showed well consistency and veracity in predicting cancer-specific survival probabilities. Conclusion: A nomogram was constructed and verified to predict survival outcomes in patients with distant-stage PNETs.

Relationship between urate within tophus and bone erosion according to the anatomic location of urate deposition in gout: A quantitative analysis using dual-energy CT volume measurements

The aim of this study was to measure the urate volume within tophus and bone erosion volume using dual-energy computed tomography in patients with tophaceous gout. Furthermore, our study aims to quantitatively analyze the relationship between monosodium urate (MSU) crystal deposition and bone erosion according to the anatomic location of urate deposition.Seventy-seven subjects with chronic gout were positively identified for the presence of urate deposition. Only 27 subjects identified for the presence of urate in contact with bone erosion were included in this study. The urate volumes and associated erosion volumes were measured. The relationships between urate within tophus and bone erosion were separately analyzed according to the anatomic location of urate deposition.Twenty-seven subjects were all male (100%) with a median (interquartile range, IQR) age of 52 (45-61) years. From all the subjects, 103 tophi depositions were identified in contact with bone erosion, including 58/103 tophi that contained an intraosseous component and 45/103 nonintraosseous tophi. Tophi containing intraosseous components were larger than nonintraosseous tophi (urate volume: median [IQR] 45.64 [4.79-250.89] mm vs 19.32 [6.97-46.71] mm, P = .035) and caused greater bone erosion (erosion volume: 249.03 [147.08-845.33] mm vs 69.07 [32.88-111.24] mm, P < .001). Almost all erosion volumes were larger than urate volumes in nonperiarticular tophi, in contrast to most erosion volumes, which were less than urate volumes in the tophi that contained a periarticular component (odds ratio, 95% confidence interval: 74.00, 14.70-372.60; P < .001). Urate volume and erosion volume demonstrated positive correlations in intraosseous tophi, intraosseous-intra-articular-periarticular tophi, and intraosseous-intra-articular tophi (rs = 0.761, rs = 0.695, rs = 0.629, respectively, P < .05).MSU crystal deposition shows a promoting effect on the development of bone erosions in varying degrees, associated with the location of MSU crystals deposited in the joints. The intraosseous tophi contribute the most to bone erosions, followed by intra-articular tophi, and periarticular tophi.

110 Patients with adenosquamous carcinomas of the pancreas (PASC): imaging differentiation of small (≤ 3 cm) versus large (> 3 cm) tumors

OBJECTIVE

This study examined radiological imaging features of small (≤ 3 cm) and large (> 3 cm) adenosquamous carcinomas of the pancreas (PASC) lesions to better understand the morphology of these lesions.

METHODS

Images from 110 patients with pathologically proven PASC (80 males and 30 females, mean age: 62.6 years) were retrospectively reviewed. Two radiologists analyzed images and reached a consensus regarding the following features: location, shape, margins, presence of solid and necrotic components, rim enhancement, density/intensity during the portal venous phase, invasion of surrounding organs, vascular invasion, venous tumor thrombus formation, and enlarged lymph nodes. Differences in the imaging features between the two groups were evaluated with the Chi-square test or Fisher's exact test.

RESULTS

There were 41 small PASC lesions (mean age: 60.59 years) and 69 large PASC lesions (63.74 years). Statistical analysis demonstrated significant differences in the location, shape, adjacent organ and vessel invasion, and venous tumor thrombus formation (P < 0.05). Small PASC lesions were more frequently detected in the pancreatic head and had an ovoid shape. There was no significant difference in the presence of solid and necrotic components (P = 0.090), including approximately 3/4 of the lesions with necrosis and 1/4 purely solid lesions, enlarged lymph nodes (P = 0.068) and other features.

CONCLUSION

Regardless of the tumor size, 75% of PASC lesions present with central necrosis while 25% are purely solid. Small PASC lesions can be associated with lymph node metastasis at a relatively early stage. Large PASC lesions are likely to invade adjacent tissues and be associated with venous tumor thrombus formation.

Computed tomography and magnetic resonance imaging features of solid serous cystadenomas of the pancreas

Solid serous cystadenomas (SSC) of the pancreas are the rarest benign type of serous cystic neoplasms and are frequently misdiagnosed, resulting in unnecessary invasive surgical procedures. A retrospective study was performed to collect imaging features of SSC using computed tomography (CT) and magnetic resonance imaging. The clinical data and imaging study of 5 female patients with pathologically confirmed SSC (mean age, 44.2 years; range, 23-69 years) diagnosed between January 2006 and July 2017 were retrospectively analyzed. The imaging study was assessed by two experienced radiologists in consensus. All patients had tumors with a mean size of 2.3 cm (range, 1.5-3.2 cm; 4/5 lesions ≤3 cm). The tumors were located in the tail of pancreas in 3 cases and in the neck of the pancreas in 2 cases. The tumors were all well defined, with an ovoid and lobulated shape and fibrous capsules. Consequently, they presented as low density on unenhanced CT images, marked hyperintensity on T2-weighted images in 4 cases and slight hyperintensity in 1 case. However, they exhibited heterogeneous wash-in and wash-out enhancement in 2 cases and moderate and prolonged enhancement in 3 cases. The apparent diffusion coefficient (ADC) values of the lesions were >2×10^-3 mm²/sec. Therefore, a small tumor size, signal intensity on T2-weighted images, high ADC values, fibrous capsules and enhancement patterns may be indicative imaging features of SSCs.

Improving the detection rate of prostate cancer in the gray zone of PI-RADS v2 and serum tPSA by using prostate-specific antigen-age volume

To improve the detection of prostate cancer (PCa) by combining the Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) and prostate-specific antigen-age volume (PSA-AV), especially among those in gray zone with PI-RADS v2 score 3 or serum total prostate-specific antigen (tPSA) 4 to 10 ng/mL.The 357 patients were enrolled in this study. The PI-RADS v2 scoring system was used to represent characteristics on multiparametric magnetic resonance imaging (mpMRI). PI-RADS v2 score 3 or tPSA 4 to 10 ng/mL were defined as the gray zone in detecting PCa. The formula equates to the patient age multiplied by the prostate volume, which is divided by the tPSA level. Univariate and multivariate analyses were done to ascertain significant predictors of prostate cancer.In all, 174 (48.7%) were benign prostatic hyperplasia, 183 (51.3%) had PCa. The results showed that PI-RADS v2, tPSA, and PSA-AV were significant independent predictors of prostate cancer. PI-RADS v2 score ≥4 could detect PCa with rate of 82.1%. Serum tPSA ≥10 ng/mL could detect PCa with rate of 66.2%, PSA density (PSAD) ≥0.15 ng/mL/cc with rate of 62.8%, and PSA-AV ≤250 with rate of 83.5%. Combining with PSA-AV ≤250, patients those with tPSA 4 to 10 ng/mL could improve the detection from 36.0% up to 81%, those with PI-RADS v2 score 3 from 28.6% up to 60.0%.PI-RADS v2 and PSA-AV are faithful variables for detecting PCa. And for patients, those in gray zones of PI-RADS v2 and tPSA, PSA-AV can improve detection rate of PCa.

Optimizing prostate cancer accumulating model: combined PI-RADS v2 with prostate specific antigen and its derivative data

BACKGROUND

To establish a new accumulating model to enhance the accuracy of prostate cancer (PCa) diagnosis by incorporating prostate-specific antigen (PSA) and its derivative data into the Prostate Imaging-Reporting and Data System version 2 (PI-RADS v2).

METHODS

A total of 357 patients who underwent prostate biopsy between January 2014 and December 2017 were included in this study. All patients had 3.0 T multiparametric magnetic resonance imaging (MRI) and complete laboratory examinations. PI-RADS v2 was used to assess the imaging. PSA, PSA density (PSAD), the free/total PSA ratio (f/t PSA) and the Gleason score (GS) were classified into four-tiered levels, and optimal weights were pursued on these managed levels to build a PCa accumulating model. A receiver operating characteristic curve was generated.

RESULTS

In all, 174 patients (48.7%) had benign prostatic hyperplasia, and 183 (51.3%) had PCa, among whom 149 (81.4%, 149/183) had clinically significant PCa. The established model 6 (PI-RADS v2 + level of PSAD + level of f/t PSA+ level of PSA) had a sensitivity and specificity of 81.4 and 84.5%, respectively, at the cut-off point of 11 in PCa diagnosis. Correspondingly, at the 12 cut-off point, the sensitivity and specificity were 87.7 and 83.0%, respectively, in diagnosing clinically significant PCa. The score of the new accumulating system was significantly different among the defined GS groups (p < 0.001). The mean values and 95% confidence intervals for GS 1-4 groups were 10.20 (9.63-10.40), 12.03 (11.19-12.87), 14.12 (13.60-14.64) and 15.44 (15.09-15.79).

CONCLUSIONS

A new PCa accumulating model may be useful in improving the accuracy of the primary diagnosis of PCa and helpful in the clinical decision to perform a biopsy when MRI results are negative.

Polysialic-Acid-Based Micelles Promote Neural Regeneration in Spinal Cord Injury Therapy

Spinal cord injury (SCI) routinely causes the immediate loss and disruption of neurons followed by complicated secondary injuries, including inflammation, oxidative stress, and dense glial scar formation. Inhibitory factors in the lesion scar and poor intrinsic neural regeneration capacity restrict functional recovery after injury. Minocycline, which has neuroprotective activity, can alleviate secondary injury, but the long-term administration of this drug may cause toxicity. Polysialic acid (PSA) is a large cell-surface carbohydrate that is critical for central nervous system development and is capable of promoting precursor cell migration, axon path finding, and synaptic remodeling; thus, PSA plays a vital role in tissue repair and regeneration. Here, we developed a PSA-based minocycline-loaded nanodrug delivery system (PSM) for the synergistic therapy of spinal cord injury. The prepared PSM exerted marked anti-inflammatory and neuroprotective activities both in vitro and in vivo. The administration of PSM could significantly protect neurons and myelin sheaths from damage, reduce the formation of glial scar, recruit endogenous neural stem cells to the lesion site, and promote the regeneration of neurons and the extension of long axons throughout the glial scar, thereby largely improving the locomotor function of SCI rats and exerting a superior therapeutic effect. The findings might provide a novel strategy for SCI synergistic therapy and the utilization of PSA in other central nervous system diseases.

A preoperative nomogram predicts prognosis of up front resectable patients with pancreatic head cancer and suspected venous invasion

BACKGROUND

Pancreatic head adenocarcinoma is commonly diagnosed at an advanced stage when adjacent vascular invasion is present. This study aimed to establish a preoperative prognostic nomogram for patients who underwent attempted curative resectional surgery for pancreatic head cancer with suspected peripancreatic venous invasion.

METHODS

Data on all consecutive patients were retrospectively collected from 2012 to 2016 at four academic institutions. The demographic and radiological parameters were analyzed using univariate and multivariate Cox regression analyses. The final nomogram was established using the concordance Harrell's C-indices and calibration curves from data obtained in three institutions and validated in the cohort of patients coming from the fourth institution.

RESULTS

The nomogram was constructed using data from 178 patients while the validation cohort consisted of 61 patients. Age, length of tumor contact, peripancreatic venous abnormalities and lymph node staging were independent factors of overall survival. The nomogram showed good probabilities of survival on calibration curves. The C-index of the model in predicting overall survival (OS) was 0.824 for the validation cohort.

CONCLUSIONS

The nomogram accurately predicted OS in patients with pancreatic head cancer with suspected peripancreatic venous invasion after attempted curative pancreatic resectional surgery.

Sialic Acid-Functionalized pH-Triggered Micelles for Enhanced Tumor Tissue Accumulation and Active Cellular Internalization of Orthotopic Hepatocarcinoma

Both targeted and stimuli-sensitive drug-delivery systems (DDSs) have been developed to augment antitumor effects. However, lack of knowledge regarding tumor tissue targeting and different effects of the stimuli-sensitive DDSs in orthotropic and ectopic tumors have impeded further advances in their clinical applications. Herein, we first reported a pH-triggered micelle with sialic acid (SA)-driven targeting ability (SA-poly(ethylene glycol)-hydrazone linker-doxorubicin (DOX), SPD). The SPD micelles encapsulated with DOX (SPDD) showed sustained drug release over 48 h in response to the pH gradient in vivo, slow under physical conditions and accelerated in the acid tumor microenvironment. In addition, the SPD micelles showed 2.3-fold higher accumulation in tumors after 48 h compared to the micelles lacking the SA moiety. The overexpression of E-selectin on the inflammatory vascular endothelial cells surrounding the tumors increased the accumulation of SPD micelles in tumor tissues, whereas that on the tumor cells increased the internalization of micelles. Consequently, SPDD micelles exerted remarkable antitumor effects in both orthotopic and ectopic models. Application of SPDD micelles in the in situ model reduced the tumor volume (77.57 mm³ vs 62.13 mm³) and metastasis after treatment for 25 days. These results suggest that SA-driven targeted DDS with a pH-responsive switch has the potential to treat hepatocarcinoma effectively both ectopically and orthotopically.

The "extracapsular cystic" sign in pancreatic serous cystic neoplasms: A clinicopathologic study of 177 patients with cystic pancreatic lesions

OBJECTIVE

To assess a new imaging feature that we have named the extracapsular cystic sign which can make a constructive contribution towards differentiating serous cystic neoplasms (SCNs) from other pancreatic cystic lesions.

MATERIAL AND METHODS

We retrospectively reviewed 177 CTs/MRIs of patients who underwent pancreatic resection of cystic lesions at two institutions from January 2011/2013, to September 2017. For each patient, demographic information, clinical presentation, especially imaging features were carefully investigated by two experienced abdominal radiologists, retrospectively. All statistical analyses were performed using SPSS V.23.0.

RESULTS

Twenty-one lesions had extracapsular cystic signs which were newly discovered, 17 (28.3%) of 60 SCNs and 4 (3.4%) (mucinous cystic neoplasm = 1, walled-off necrosis = 2, retention cyst = 1) of 117 Non-SCNs were included, from which indicating that the extracapsular cystic sign was more often detected on SCNs. As for 21 lesions, 86% (n = 18) were females, and mean age at diagnosis was 51.2 years. 71% (n = 15) located in the pancreatic body and tail. Average size was 27.2 mm (23.7-53.4), mean (SD) ratio of biggest daughter cyst to mother cyst was 0.51[0.14] (p = 0.99), average (SD) angle between two of them was 105.5° [14.9] (p = 0.84). The average time interval between last imaging examination and surgery was 8.4 days.

CONCLUSIONS

The new sign named the extracapsular cystic sign in SCNs may help differentiate SCNs from other pancreatic cystic lesions. Furthermore, this study supports an original diagnosis for SCNs when the sign of extracapsular cyst appears.

Visual targeted therapy of hepatic cancer using homing peptide modified calcium phosphate nanoparticles loading doxorubicin guided by T1 weighted MRI

Effective treatment and real-time monitoring of hepatic cancer are essential. A multifunctional calcium phosphate nanoparticles loading chemotherapeutic agent doxorubicin and magnetic resonance imaging contrast agent diethylenetriaminepentaacetic acid gadolinium (A54-CaP/Gd-DTPA/DOX) was developed for visual targeted therapy of hepatic cancer via T1-weighted MRI in real-time. A54-CaP/Gd-DTPA/DOX exhibited a higher longitudinal relaxivity (6.02 mM^-1 s^-1) than commercial MR contrast agent Gd-DTPA (3.3765 mM^-1 s^-1). The DOX release from the nanoparticles exhibited a pH dependent behavior. The cellular uptake results showed that the internalization of A54-CaP/Gd-DTPA/DOX into BEL-7402 cells was1.9-fold faster than that of HepG2 cells via A54 binding. In vivo experiments presented that A54-CaP/Gd-DTPA/DOX had higher distribution and longer retention time in tumor tissue than CaP/Gd-DTPA/DOX and free DOX, and also displayed great antitumor efficacy (95.38% tumor inhibition rate) and lower toxicity. Furthermore, the Gd-DTPA entrapped in the nanoparticles could provide T1-weighted MRI for real-time monitoring the progress of tumor treatment.

A five year CT surveillance of ciliated retroperitoneal foregut cyst resembling a cystic pancreatic lesion: A case report

INTRODUCTION

Ciliated retroperitoneal foregut cysts are rare, and to obtain a preoperative definitive diagnosis of this condition is relatively difficult. In addition, the exact mechanism and formation of ciliated retroperitoneal foregut cysts remains unknown.

CASE PRESENTATION

Here, we report a case of a 47-year-old woman who presented with an unusual shaped cystic lesion associated with a patch of solid components between the pancreas and the left kidney, initially misdiagnosed as a cystic pancreatic lesion 5 years previously to presentation at our clinic. During the past years, reports relating to the surveillance of these lesions described that their shapes progressively change while its volumes remain invariably unchanged. We did not observe this phenomenon in any literatures to our knowledge. The patient was diagnosed with ciliated retroperitoneal foregut cyst with remote hemorrhage, after the laparoscopic surgery.

CONCLUSIONS

Ciliated retroperitoneal foregut cysts have characteristic manifestations. From this case, we summarized that cysts in the retroperitoneum, associated with a changing shape of the lesion, highly suggest the diagnosis of foregut cysts, which are safe under long-term surveillance.

Lymphadenitis associated with cat-scratch disease simulating a neoplasm: Imaging findings with histopathological associations

The lymphadenitis associated with cat-scratch disease (CSD) is often confused with neoplasms by a number of radiologists and clinicians, and consequently, unnecessary invasive procedures or surgeries are performed. In the present study, the contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) findings of 10 patients (6 men and 4 women) with clinically and pathologically confirmed lymphadenitis associated with CSD were retrospectively analyzed (CT in 3 patients, MRI in 6 patients, and CT and MRI in 1 patient) at The Second Affiliated Hospital of Zhejiang University School of Medicine (Hangzhou, China) between January 2007 and November 2014. As a result, 17 enlarged lymph nodes were identified in 10 cases. The 5 nodes identified by CT scan exhibited relatively inhomogeneous isodensity to muscle, with patchy low density in the center. All 14 nodes identified by MRI scan exhibited homogeneous or heterogeneous isointensity to muscle or slightly increased intensity compared with that of muscle on T1-weighted images (T1WI), and homogeneous or heterogeneous hyperintensity on fat-suppressed T2WI. Following enhancement, all 17 enlarged lymph nodes associated with CSD demonstrated the following 3 different enhancement patterns: Moderate homogeneous enhancement (n=8), which was associated with histologically identified early disease stage; marked heterogeneous enhancement with no enhancement of the necrotic areas (n=4), and heterogeneous enhancement with progressively ‘spoke-wheel-like’ (defined as radiating enhancement from the center) enhancement of the patchy low-density area (n=1), which was associated with histologically identified intermediate disease stage; and astral low-density/hypointensity with marked enhancement (n=2) or a ‘rose flower’ sign (n=2), which was associated with histologically identified late disease stage. We hypothesized that the CT and MRI results of lymphadenitis in CSD may be associated with the pathological features. It may be suggested that the diagnosis of CSD may be formed when considering the characteristic CT and MRI features of astral low-density/hypointensity with marked enhancement or a ‘rose flower’ sign (defined as marginal petaloid enhancement) in the late disease stage, or the MRI results of homogeneous, moderate enhancement in the early disease stage, or the CT/MRI data of heterogeneous enhancement with non-enhancing area in the center in the intermediate disease stage, in solitary or multiple enlarged lymph nodes associated with general subcutaneous edema in the vicinity of the nodes on CT/MRI and with a history of cat exposure.

T2-Weighted Magnetic Resonance Imaging of Hepatic Tumor Guided by SPIO-Loaded Nanostructured Lipid Carriers and Ferritin Reporter Genes

Nowadays, there is a high demand for supersensitive contrast agents for the early diagnostics of hepatocarcinoma. It has been recognized that accurate imaging information is able to be achieved by constructing hepatic tumor specific targeting probes, though it still faces challenges. Here, a AGKGTPSLETTP peptide (A54)-functionalized superparamagnetic iron oxide (SPIO)-loaded nanostructured lipid carrier (A54-SNLC), which can be specifically uptaken by hepatoma carcinoma cell (Bel-7402) and exhibited ultralow imaging signal intensity with varied Fe concentration on T2-weighted imaging (T2WI), was first prepared as an effective gene carrier. Then, an endogenous ferritin reporter gene for magnetic resonance imaging (MRI) with tumor-specific promoter (AFP-promoter) was designed, which can also exhibit a decrease in signal intensity on T2WI. At last, using protamine as a cationic mediator, novel ternary nanoparticle of A54-SNLC/protamine/DNA (A54-SNPD) as an active dual-target T2-weighted MRI contrast agent for imaging hepatic tumor was achieved. Owing to the synergistic effect of A54-SNLC and AFP-promoted DNA targeting with Bel-7402 cells, T2 imaging intensity values of hepatic tumors were successfully decreased via the T2 contrast enhancement of ternary nanoparticles. It is emphasized that the novel A54-SNPD ternary nanoparticle as active dual-target T2-weighted MRI contrast agent were able to greatly increase the diagnostic sensitivity and specificity of hepatic cancer.

Contrast-enhanced multiple-phase imaging features of intrahepatic mass-forming cholangiocarcinoma and hepatocellular carcinoma with cirrhosis: A comparative study

The intrahepatic mass-forming cholangiocarcinoma (IMCC) is frequently misdiagnosed as hepatocellular carcinoma (HCC) in patients with cirrhosis, by numerous radiologists and clinical doctors, which results in the incorrect therapeutic treatment. A retrospective case-control study was conducted, and the contrast-enhanced multiple-phase (CEMP) computed tomography (CT) and magnetic resonance imaging (MRI) findings of 22 pathologically confirmed IMCC patients and 22 HCC controls with underlying liver cirrhosis were analyzed at the present hospital, from January 2010 to December 2015. In addition, serum tests were conducted and clinical symptoms of patients evaluated. A statistical analysis revealed that the enhancement pattern, signal on MRI delayed phase (P<0.001), maximum diameter, capsule retraction, portal vein invasion, bile duct dilation and abdominal lymphadenectasis characteristics were different between IMCC and HCC patients with cirrhosis. On CEMP CT and MRI analysis, the most frequently occurring enhancement patterns of IMCC were progressive patterns (P=0.001 or P<0.001). Conversely, the most frequently occurring enhancement patterns present in HCC were the washout patterns (P<0.001). Therefore, the diagnosis of IMCC in cirrhotic patients should be verified with CEMP CT and MRI analysis for the future, to determine presence or absence of progressive and/or peripheral rim-like enhancement, a hyperintensive delayed phase with capsule retraction, portal vein invasion, bile duct dilation, abdominal lymphadenectasis and increased levels of CA199.

Modified-FOLFIRINOX in metastatic pancreatic cancer: A prospective study in Chinese population

FOLFIRINOX chemotherapy has shown remarkable responses in patients with metastatic pancreatic cancer (MPC), and has significantly improved prognosis. However, FOLFIRINOX is currently not frequently applied in China because of its high incidence of adverse events, and there is no recognized optimization for this therapy in Chinese population. Modification of FOLFIRINOX may be better for its acceptance in China. In this study, we evaluated the efficacy and safety of modified-FOLFIRINOX in patients with MPC. A total of 62 MPC patients were treated with modified-FOLFIRINOX (no Fluorouracil bolus, 85% Oxaliplatin and 75% Irinotecan) between April 2014 and April 2017 in our institute. 40 of them were evaluated, with a response rate of 32.5% (13/40). The frequent grade 3/4 adverse events are neutropenia (29%) and alanine aminotransferase elevation (14.5%). No treatment-related death was observed. The median overall survival and median progression-free survival are 10.3 months and 7.0 months, respectively. In conclusion, modified-FOLFIRINOX had significantly improved tolerance with similar efficacy to FOLFIRINOX. These findings may provide evidence for the use of FOLFIRINOX in Chinese patients with MPC.

The ability of the Coincidence Doppler Broadening Spectroscopy to characterize polymers containing different chemical elements

Hydrocarbon polymers, O-containing, F-containing and Cl-containing polymers are comprehensively studied by Coincidence Doppler Broadening Spectroscopy (CDBS). It is shown that for polymers with different chemical structure, CDBS results can effectively distinguish polar groups CO, CCl, and CF. For polymers with similar chemical structure, the intensity of the element-specific peak in the CDBS ratio curve is dependent not only on the fraction of free positrons, but also on the content of characteristic atom in polymer repeated unit, and the polarity of the polymer molecule. For polymers containing several different polar groups, such as PCTFE (CF & CCl) and PFA (CF & CO), whether the element-specific peak appears or not depends on the amount of the polar groups and its positron capture ability. This work may provide insights into potential applications of CDBS for studying complex polymer systems.

Multifunctional SPIO/DOX-loaded A54 Homing Peptide Functionalized Dextran-g-PLGA Micelles for Tumor Therapy and MR Imaging

Specific delivery of chemotherapy drugs and magnetic resonance imaging (MRI) contrast agent into tumor cells is one of the issues to highly efficient tumor targeting therapy and magnetic resonance imaging. Here, A54 peptide-functionalized poly(lactic-co-glycolic acid)-grafted dextran (A54-Dex-PLGA) was synthesized. The synthesized A54-Dex-PLGA could self-assemble to form micelles with a low critical micelle concentration of 22.51 μg. mL⁻¹ and diameter of about 50 nm. The synthetic A54-Dex-PLGA micelles can encapsulate doxorubicin (DOX) as a model anti-tumor drug and superparamagnetic iron oxide (SPIO) as a contrast agent for MRI. The drug-encapsulation efficiency was about 80% and the in vitro DOX release was prolonged to 72 hours. The DOX/SPIO-loaded micelles could specifically target BEL-7402 cell line. In vitro MRI results also proved the specific binding ability of A54-Dex-PLGA/DOX/SPIO micelles to hepatoma cell BEL-7402. The in vivo MR imaging experiments using a BEL-7402 orthotopic implantation model further validated the targeting effect of DOX/SPIO-loaded micelles. In vitro and in vivo anti-tumor activities results showed that A54-Dex-PLGA/DOX/SPIO micelles revealed better therapeutic effects compared with Dex-PLGA/DOX/SPIO micelles and reduced toxicity compared with commercial adriamycin injection.

Desmoplastic small round cell tumor: A case report of a rare differential diagnosis of solid tumors of the pleura

Desmoplastic small round cell tumor (DSRCT) presents as a rare separate clinical pathological entity, and pleural DSRCT is very rare. Following review of the English literatures it was revealed that, to date, <15 cases of primary DSRCT of the pleura have been reported worldwide. Among these, there are few computed tomography (CT) findings of pleural DSRCT which have previously been described in detail. The present study reports a pathologically proven case of pleural DSRCT, with varying contrast CT findings in a 72-year-old female, which appeared as a large (12.0×10.0×6.5 cm), smooth, oval mass in the left lower thorax with slight-moderate uniform enhancement on contrast-enhanced CT. To the best of our knowledge, the present report is the first to describe the large solid-tumor pattern and the patient is the eldest reported case of pleural DSRCT.

Multiple-phase spiral CT findings of pancreatic vasoactive intestinal peptide-secreting tumor: A case report

The present study reports a case of pancreatic vasoactive intestinal peptide-secreting tumor (VIPoma), of 2.2 cm in diameter, arising from the region of the uncus of the pancreas with liver metastases in a 50-year-old patient, which demonstrated unusual multiple-phase spiral computed tomography (MPSCT) results. The pancreatic lesion was isodense compared with the pancreatic parenchyma. During the hepatic artery phase and portal venous phase, the mass was hypodense compared with the enhanced pancreas, with the mean CT attenuation (HU) values being 56 HU and 66 HU, respectively. During the hepatic parenchymal phase, the mass became hyperdense with the mean CT attenuation values being 74 HU. The process of contrast-enhanced MPSCT demonstrated progressive strengthening. Pancreaticoduodenectomy and wedge resection of a number of the liver metastases was performed. There are only a limited number of studies reporting CT findings of pancreatic VIPoma and no MPSCT findings have been described previously.

Eosinophilic gastroenteritis associated with eosinophilic cystitis: Computed tomography and magnetic resonance imaging findings

Eosinophilic gastroenteritis (EG) is a rare, distinct clinical entity, and EG associated with eosinophilic cystitis (EC) is extremely rare and has not been well documented. Here, we report two cases of EG and coexistent EC along with findings from computed tomography (CT) and magnetic resonance imaging (MRI). An 18-year-old male with a history of hematuria, urgency and occasional urodynia for two weeks and a 34-year-old male with a history of abdominal distention for one week were admitted to our hospital. Abdominal contrast-enhanced CT in both patients revealed wall thickening in different parts of the gastrointestinal tract with inhomogeneous reinforcement, coexistent with local or diffuse bladder wall thickening with progressive enhancement, and also showed that the bladder mucosal lining was nondestructive. Pelvic MRI showed that the local or diffuse thickened bladder wall was iso-intense on T1-weighted images, hypo-intense on T2-weighted images, and slightly restricted on diffusion weighted imaging (DWI) in one case. After therapy, the thickened wall of the gastrointestinal tract and urinary bladder had improved markedly in the two cases. To the best of our knowledge, this is the first report on the radiological imaging of EG and coexistent EC by both CT and MRI and the first with DWI findings.