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Purpose: We aim to compare the clinical outcomes of radical nephroureterectomy with bladder cuff removal (RNU) and segmental resection with ureteral reimplantation (RR) in Chinese patients with distal ureteral urothelial carcinoma. Materials and Methods: A retrospective analysis of medical records was performed for 922 patients found to have distal ureteral cancer, defined as below the level of the iliac vessels, with 747 patients who underwent RNU and 175 who underwent RR included in the final analysis. The primary endpoints included clinical outcomes and changes in the estimated glomerular filtration rate (eGFR). Survival analysis was conducted using the Kaplan–Meier method, and propensity score matching (PSM) was utilized to mitigate selection bias between the two surgical approaches. Results: After PSM, the Kaplan–Meier survival curves demonstrated significant associations between surgical approach and both local recurrence-free survival (LRFS) and bladder recurrence-free survival (BRFS), but no significant differences were found in cancer-specific survival (CSS) and overall survival (OS). There were no significant differences in metastasis-free survival and contralateral recurrence-free survival between the two groups. Multivariate Cox regression analysis identified RR as an independent predictor of poorer outcomes for LRFS and BRFS. In addition, a significant increase in eGFR was observed following RR, whereas a significant decrease was noted after RNU. Conclusion: RR is associated with equivalent CSS and OS compared with RNU, even in the context of high-risk distal ureteral cancer, and results in improved postoperative eGFR, whereas the potential of RR to increase the risk of local tumor recurrence and intravesical recurrence requires clinical consideration. [ABSTRACT FROM AUTHOR]

Background: Primary mesenchymal tumors of the prostate are very rare, and there is no systematic report on fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET/CT). The aim of this research was to characterize mesenchymal tumors of the prostate on 18F-FDG PET/CT. Results: We included 13 patients with pathologically confirmed mesenchymal neoplasms of the prostate. The location, size, maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total glycolysis of the lesion (TLG), pathologic findings, and available imaging study of the tumors were reviewed. Of the 13 patients (median age, 38 years; ranged from 13 to 74 years), the mean size of the tumors was 8.8 cm in diameter ranged from 5 to 16.1 cm. SUVmax ranged from 3.1 to 17.6 (mean 9.5), MTV ranged from 4.9 to 398 cm3 (mean 109 cm3) and TLG ranged from 21.3 to 1216 g (mean 96 g). The seminal vesicles, rectum, and bladder are the most commonly affected sites of invasion, while metastasis typically occurs in the bones, lungs, and lymph nodes. Conclusions: Mesenchymal tumors of the prostate revealed large sizes and high SUVmax, MTV and TLG levels on 18F-FDG PET/CT. 18F-FDG PET/CT may be useful for accurate diagnosis, staging, and restaging, which plays an important role in the management of subsequent plans. [ABSTRACT FROM AUTHOR]

Radiomics aims to develop novel biomarkers and provide relevant deeper subvisual information about pathology, immunophenotype, and tumor microenvironment. It uses automated or semiautomated quantitative analysis of high‐dimensional images to improve characterization, diagnosis, and prognosis. Recent years have seen a rapid increase in radiomics applications in nuclear medicine, leading to some promising research results in digestive system oncology, which have been driven by big data analysis and the development of artificial intelligence. Although radiomics advances one step further toward the non‐invasive precision medical analysis, it is still a step away from clinical application and faces many challenges. This review article summarizes the available literature on digestive system tumors regarding radiomics in nuclear medicine. First, we describe the workflow and steps involved in radiomics analysis. Subsequently, we discuss the progress in clinical application regarding the utilization of radiomics for distinguishing between various diseases and evaluating their prognosis, and demonstrate how radiomics advances this field. Finally, we offer our viewpoint on how the field can progress by addressing the challenges facing clinical implementation. [ABSTRACT FROM AUTHOR]

In order to study the influence of pillar stopping blasting on the stability of cemented backfill, the dynamic impact test under low strain rate (61.1∼86.8 s−1) was conducted on cemented backfill with two kinds of strength using three-dimensional coupled static-dynamic SHPB equipment. At the same time, the strain rate effect of failure mode, dynamic strength factor, and energy transfer of backfill were analyzed. The results show that when the cemented backfill was loaded under different strain rates in the initial three-dimensional static pressure environment, the pore compaction process was no longer obvious but directly entered the elastic deformation stage. Within the range of strain rates, the extreme value of dynamic intensity factor (DIF) of CTB230 was 6.8, while the extreme value of dynamic intensity factor of CTB310 specimen did not appear within the range of strain rates due to the improvement of the internal cementation force between particles. The fracture surfaces of specimens were perpendicular to the direction of load, and the failure mode was mainly the axial tensile failure, and the fracture surfaces were mostly close to the loading end. According to energy calculation, reflected energy accounts for 80.4%∼86.6% of incident energy; dissipated energy, 5.5%∼14.3%; transmitted energy, 5.3%∼7.9%. [ABSTRACT FROM AUTHOR]

In order to accurately predict the blasting results and reduce the damage of blasting vibration to the building and ensure the safety of workers, BP neural network with the ability to deal with nonlinear problems was used to forecast the blasting results. Qualified blasting results were selected as the learning samples of the network model, after a certain number of times of training and learning, the feed forward characteristics of the neural network were applied to determine the thresholds and errors of each layer, then the establishment of BP neural network was completed. Results indicated that the error between the prediction result and the real result was within 10%, which conformed to the engineering requirements. By combining PAC algorithm, POS algorithm or MATLAB to optimize the network, the error can even be controlled within 5%. The damage caused by blasting operation can be reduced by establishing BP neural network prediction, with safety cost reduced and guiding the construction of blasting operation. [ABSTRACT FROM AUTHOR]

A two-transistor and two-magnetic-tunnel-junction (MTJ) multi-level cell (MLC) structure of spin-transfer torque magnetic random access memory (STT-RAM) is proposed. Compared with the conventional one-transistor and two-magnetic-tunnel-junction MLC STT-RAMs, by adding an extra access transistor and adjusting the connection of the two MTJs, the extra write power consumption on the soft bit MTJ can be reduced, which will also have a benefit to the lifetime of the soft bit. Specifically, the simulation results show that more than 75% write power consumption on the soft bit can be wiped out, and the area cost caused by the extra access transistor is negligible. [ABSTRACT FROM AUTHOR]

Buccal mucosal graft (BMG) ureteroplasty, particularly with the anterior-onlay technique, shows promise for treating complex ureteral strictures. However, long and circumferential strictures remain challenging. This study aimed to present the surgical technique of the posterior-inlay and anterior-onlay technique in robotic ureteroplasty with a BMG (RU-BMG). A 37-year-old male patient with a medical background of failed laparoscopic ureteroplasty and multiple endourological interventions was admitted to our hospital. Preoperative anterograde and retrograde pyelography revealed a 5-cm ureteral stricture. During the surgical procedure, the ureteral posterior wall was insufficient to facilitate a complete posterior augmented anastomosis, resulting in a posterior defect subsequent to the partial posterior augmented anastomosis. Ultimately, a BMG was utilized to address the posterior defect initially, followed by anterior-onlay ureteroplasty with a BMG. The Foley catheter was removed 2 weeks after surgery, while the nephrostomy tube was clamped on postoperative day 14. The double-J stent was removed 3 months after surgery. The preoperative serum creatine was 102.9 μmol/L. The surgery was performed successfully within 240 min, with estimated blood loss of 100 mL. The postoperative hospitalization was 4 days. Throughout the 12-month follow-up period, no symptoms or complications were observed, with a serum creatine of 82.0 μmol/L. Computed tomography urography indicated relieved hydronephrosis. In conclusion, RU-BMG using a combination of posterior-inlay and anterior-onlay technique is safe and feasible in the management of ureteral stricture. More cases and longer follow-up for this procedure are needed for better perfection of this procedure., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tau.amegroups.com/article/view/10.21037/tau-24-335/coif). The authors have no conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)

Abstract: Primary small cell carcinoma of the ureter is an extremely rare malignancy with a poor prognosis. We present rare interesting 18 F-FDG PET/CT images of primary small cell carcinoma of the ureter in a 37-year-old man with early recurrence and multiple metastases 2 months after laparoscopic left nephroureterectomy and pelvic tumor resection. PET/CT showed high FDG-avid lesions in the pelvis, peritoneum, the left posterior wall of the bladder, and in the right lung, providing important value in the detection of recurrence and systemic metastases., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasm arising from gastrointestinal tract and can be benign or malignant. Rectal GISTs are rare and have poor prognosis. We here reported an older male who presented with features of distending discomfort in the rectum and pain in the anus due to a large rectal tumor. Physical examinations detected a mass in the rectum without blood staining on the gloved finger. Carcinoembryonic antigen (CEA) was found to be slightly elevated and the prostate-specific antigen level was normal. 18 F-FDG PET/CT showed a soft tissue density mass at the bottom of the pelvic, with an unclear boundary to the surroundings with the significantly increased FDG uptake (SUVmax 17.5). Although a rectal carcinoma was suspected based on the finding of PET/CT and CEA, the histopathological examination confirmed the diagnosis of the malignant GIST of the rectum. The patient was then treated with imatinib and on follow-up regularly. In this case, 18 F-FDG PET/CT shows the advantage of visualizing both primary and metastatic lesions and provides valuable information for the diagnosis, staging, evaluation, and prognosis of GIST., Competing Interests: None., (AJNMMI Copyright © 2023.)