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Background: Post-radiation nasopharyngeal necrosis (PRNN) is a severe adverse event following re-radiotherapy for patients with locally recurrent nasopharyngeal carcinoma (LRNPC) and associated with decreased survival. Biological heterogeneity in recurrent tumors contributes to the different risks of PRNN. Radiomics can be used to mine high-throughput non-invasive image features to predict clinical outcomes and capture underlying biological functions. We aimed to develop a radiogenomic signature for the pre-treatment prediction of PRNN to guide re-radiotherapy in patients with LRNPC. Methods: This multicenter study included 761 re-irradiated patients with LRNPC at four centers in NPC endemic area and divided them into training, internal validation, and external validation cohorts. We built a machine learning (random forest) radiomic signature based on the pre-treatment multiparametric magnetic resonance images for predicting PRNN following re-radiotherapy. We comprehensively assessed the performance of the radiomic signature. Transcriptomic sequencing and gene set enrichment analyses were conducted to identify the associated biological processes. Results: The radiomic signature showed discrimination of 1-year PRNN in the training, internal validation, and external validation cohorts (area under the curve (AUC) 0.713–0.756). Stratified by a cutoff score of 0.735, patients with high-risk signature had higher incidences of PRNN than patients with low-risk signature (1-year PRNN rates 42.2–62.5% vs. 16.3–18.8%, P < 0.001). The signature significantly outperformed the clinical model (P < 0.05) and was generalizable across different centers, imaging parameters, and patient subgroups. The radiomic signature had prognostic value concerning its correlation with PRNN-related deaths (hazard ratio (HR) 3.07–6.75, P < 0.001) and all causes of deaths (HR 1.53–2.30, P < 0.01). Radiogenomics analyses revealed associations between the radiomic signature and signaling pathways involved in tissue fibrosis and vascularity. Conclusions: We present a radiomic signature for the individualized risk assessment of PRNN following re-radiotherapy, which may serve as a noninvasive radio-biomarker of radiation injury-associated processes and a useful clinical tool to personalize treatment recommendations for patients with LANPC. [ABSTRACT FROM AUTHOR]

Background: Previous researches on large animal models of diabetic cardiomyopathy were insufficient. The aim of this study was to evaluate early changes in left ventricular (LV) function and morphology in diabetic pigs using a cardiac magnetic resonance (CMR) time-volume curve and feature tracking technique. Methods: Streptozotocin (STZ) was used to induce diabetic in sixteen pigs. 3.0T MRI scanned the pig's heart before and 2, 6, 10 and 16 months after modelling. CMR biomarkers, including time-volume curve and myocardial strain, were compared to analyse the longitudinal changes in LV function and morphology. Pearson correlation was used to evaluate the relationship between LV strain and remodelling. Cardiac specimens were obtained at 6, 10, and 16 months after modelling to observe the myocardial ultrastructural and microstructure at different courses of diabetes. Results: Twelve pigs developed diabetes. The 80% diastolic volume recovery rate (DVR) at 6 months after modelling was significantly higher than that before modelling (0.78 ± 0.08vs. 0.67 ± 0.15). The LV global longitudinal peak strain (GLPS) (− 10.21 ± 3.15 vs. − 9.74 ± 2.78 vs. − 9.38 ± 3.71 vs. − 8.71 ± 2.68 vs. − 6.59 ± 2.90%) altered gradually from the baseline data to 2, 6, 10 and 16 months after modelling. After 16 months of modelling, the LV remodelling index (LVRI) of pigs increased compared with that before modelling (2.19 ± 0.97 vs. 1.36 ± 0.45 g/ml). The LVRI and myocardial peak strain were correlated in diabetic pigs (r= − 0.40 to − 0.54), with GLPS being the most significant. Electron microscopy and Masson staining showed that myocardial damage and fibrosis gradually increased with the progression of the disease. Conclusion: Intravenous injection of STZ can induce a porcine diabetic cardiomyopathy model, mainly characterized by decreased LV diastolic function and strain changes accompanied by myocardial remodelling. The changes in CMR biomarkers could reflect the early myocardial injury of diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the correlation between the histopathology of the kidney and clinical indicators in patients with lupus nephritis (LN) using magnetic resonance imaging (MRI). Methods: A total 50 female participants were enrolled in the study. Thirty patients with LN were divided into types 2, 3, 4, and 5, according to their pathological features. The control group consisted of 20 healthy female volunteers. Serum creatinine, C3, C1q, and anti-ds-DNA were measured. Conventional MRI, DTI, DWI, and BOLD scanning was performed to obtain the FA, ADC, and R2* values for the kidney. Results: Compared with the control group, FA and the ADC were decreased in patients with LN, while the R2* value was increased (P < 0.05). The overall comparison of the SLEDAI (Activity index of systemic lupus erythematosus) score, total pathological score, AI, and serum creatinine C3 showed that these were significantly different between the two groups (P < 0.05). FA and the ADC were negatively correlated with urinary, blood ds-DNA, and serum creatinine and positively correlated with C1q (P < 0.05). The R2* value was positively correlated with urinary NGAL, blood ds-DNA, and serum creatinine (P < 0.05). FA and the ADC were negatively correlated with the SLEDAI score, total pathological score, AI, CI, nephridial tissue C3, and C1q. The R2* value was positively correlated with the SLEDAI score, total pathological score, AI, CI, nephridial tissue C3, and C1q (P < 0.05). Conclusions: MRI examination in female patients with LN was correlated with pathologic test results, which may have clinical significance in determining the disease's severity, treatment, and outcome. [ABSTRACT FROM AUTHOR]

Background: Mixed neuroendocrine–non-neuroendocrine neoplasms (MiNENs) of the gallbladder are rare malignancies. Here we presented two cases and reviewed the related literature. Case presentation: Our two patients were postoperatively diagnosed with gallbladder MiNENs, which pathologically consisted of a large cell neuroendocrine carcinoma and papillary adenocarcinoma. After cholecystectomy, one patient had a survival time of 30 months, while the other remained alive through 12 months of follow-up. In the literature, a total of 72 cases of gallbladder MiNENs were identified, and with our two patients included, we calculated a male-to-female ratio of 0.22 and a mean age of 64.5 years for the 74 reported cases. About one-half of these patients were found to have gallstones and presented with abdominal pain or discomfort in a relatively early stage. The preoperative diagnosis of these 74 cases mainly relied on abdominal ultrasound, contrast-enhanced computed tomography (CT) scanning, and magnetic resonance imaging or positron emission tomography/CT. However, the final diagnosis was established based upon the pathological evidence and expression of synaptophysin (Syn) and/or chromogranin A identified by immunohistochemical staining or neurosecretory granules detected by electron microscopy. Fifty-eight patients (78.4%) underwent various operations including simple cholecystectomy (n = 14), en bloc cholecystectomy (n = 9), standard or non-standard radical cholecystectomy (n = 25), or extended radical cholecystectomy (n = 6). The mean size of the resected gallbladder masses was 50.8 ± 36.1 mm (n = 63) with regional lymph node metastasis in 37 patients (52.1%), liver invasion or staging greater than T3 in 33 patients (45.8%), and hepatic metastasis in 26 patients (35.1%). The postoperative median survival time was 36 ± 11.42 months (95% confidence interval, 13.62 to 58.38 months). The log-rank analysis did not find that postoperative adjuvant chemotherapy contributed to a longer survival time relative to that among the patients who did not receive chemotherapy (numbers of patients, 15 versus 43; survival times, 36 months versus 30 months, p > 0.05). Conclusions: Our two cases and the cases in the literature suggest that MiNENs of the gallbladder predominantly occur in women; are associated with early lymph node metastasis, local hepatic invasion, and hepatic metastasis; and can be managed by various surgeries as well as chemotherapy combined with somatostatin analogs. [ABSTRACT FROM AUTHOR]

Background: To determine whether magnetic resonance imaging (MRI)-detected extramural vascular invasion (mrEMVI) status is associated with quantitative perfusion parameters derived from dynamic contrast-enhanced MRI (DCE-MRI) in rectal cancer.Methods: Seventy-two patients with rectal adenocarcinoma who underwent curative surgery alone within 2 weeks following rectal MRI were enrolled in this retrospective study. mrEMVI status was determined based on high-resolution MRI. The quantitative perfusion parameters (Ktrans, kep and ve) derived from DCE-MRI were calculated from all sections containing tumours. DCE-MRI parameters and clinicopathological variables in patients with different mrEMVI statuses were compared.Results: For patients who were mrEMVI positive, the tumours demonstrated significantly lower kep values (P = 0.012) and higher ve values (P = 0.021) than tumours of patients who were mrEMVI negative, while the Ktrans value displayed no significant difference (P = 0.390). The patients who were mrEMVI positive had larger tumour size, higher pathological tumour stage and increased regional nodal metastases compared to those who were mrEMVI negative (2.9 cm vs. 3.5 cm, P = 0.011; 63.8% vs. 92.0%, P = 0.010; 36.2% vs. 76.0%, P = 0.001; respectively).Conclusions: This study demonstrated for the first time that tumour microcirculation is altered in mrEMVI-positive patients with rectal adenocarcinoma, as evidenced by significantly lower kep and higher ve values. In addition, these patients were more likely to have a larger tumour size, a higher pathological tumour stage and regional nodal metastases than mrEMVI-negative patients. [ABSTRACT FROM AUTHOR]