Objective:To investigate the risk factors for detecting clinically significant prostate cancer (CSPCa) in patients with Prostate Imaging Reporting and Data System (PI-RADS) score≤3 on multi-parameter magnetic resonance imaging (mpMRI).Methods:Retrospective analysis was performed on the case data of 335 patients with suspected prostate cancer and PI-RADS score ≤3 who were admitted to Beijing Friendship Hospital, Capital Medical University from January 2013 to October 2022. All patients underwent 24-needle prostate biopsy. Clinical data such as age, body mass index, past medical history, serological laboratory indicators, and mpMRI imaging data were collected. The patients were grouped according to whether the puncture pathology was CSPCa or not, and the differences in clinical data between the two groups were analyzed by t-test, rank sum test and Chi-test. Multivariate Logistic regression analysis was further used to determine independent risk factors for MRI invisible prostate cancer, and receiver operating characteristics (ROC) curves were drawn. At the same time, further subgroup analysis was conducted based on whether prostate-specific antigen (PSA) was positive before puncture and PI-RADS score, respectively, and the same statistical method was used to further determine the influence of different serological indicators and PI-RADS score on the analysis results of risk factors. Results:Among all patients, 81 were CSPCa patients and 254 were non-CSPCa patients. Multivariate Logistic regression analysis showed that prostate-specific antigen density (PSAD) and PI-RADS score of 3 were independent risk factors for MRI invisible prostate cancer. At the same time, compared with suspected lesions located only in the transitional zone, the incidence of CSPCa in patients with suspected lesions located in the peripheral zone would increase, and the incidence of CSPCa would further increase when suspected lesions were found in both the transitional zone and the peripheral zone. In PSA-negative patients, only suspected lesion location was an independent risk factor for MRI invisible prostate cancer, while in PSA-positive patients, prostate volume, PSAD, and PI-RADS scores were independent risk factors. In subgroup analysis with different PI-RADS scores, suspicious lesions in both the transitional zone and peripheral zone indicate a higher likelihood of CSPCa. For patients with PI-RADS scores of 1 to 2, suspicious lesions in the peripheral zone alone may also indicated CSPCa, while for patients with PI-RADS scores of 3, the lower free prostate-specific antigen/total prostate-specific anti-principle was more accurate in predicting CSPCa.Conclusions:For patients who are clinically suspected of prostate cancer but whose PI-RADS score is less than or equal to 3 points indicated by mpMRI, it is necessary to further focus on the results of different serological indicators according to whether their PSA is positive and PI-RADS score respectively to judge whether patients should receive systemic prostate puncture, instead of using PSA level as a single indication for puncture. At the same time, clinicians should also pay full attention to the location of suspected lesions, when they are located in the peripheral zone, or there are suspected lesions in both the peripheral zone and the transitional zone, the possibility of CSPCa should be fully considered.

Objective:To investigate the rate-limiting steps of hand-assisted laparoscopic donor nephrectomy, analyze the relevant factors affecting surgical difficulty, and subsequently construct a mathematical model to predict the difficulty of the procedure preoperatively.Methods:A retrospective study was conducted on 100 kidney donors who underwent hand-assisted laparoscopic donor nephrectomy performed by the same surgeon at Beijing Friendship Hospital, Capital Medical University from January 2021 to January 2024. Preoperative demographic data, imaging findings, general condition, donor kidney size, and postoperative complications were collected and analyzed. The surgeon′s subjective rating (1-3 points) was used as a quantitative measure of surgical difficulty. ANOVA and Chi-square tests were employed to explore the differences in postoperative complications, recovery, operative time, and intraoperative blood loss among groups with varying levels of difficulty. The main procedure was divided into four steps (excluding abdominal closure): Trocar placement, renal hilar dissection, perinephric dissection, and kidney retrieval. The time for each step and the total operative time were recorded. Pearson correlation test was used to analyze the relationship between each step and the total operative time, and ANOVA test was used to assess the time differences between steps and to determine if the time for the same step varied across different difficulty subgroups, thereby identifying the rate-limiting step of hand-assisted laparoscopic donor nephrectomy. In terms of the risk factors influencing the difficulty of surgery, Pearson and Spearman correlation tests were used to investigate the relationship between preoperative donor data and surgical difficulty scores, and a predictive model was constructed using multiple linear regression. Finally, the model was internally and externally validated to confirm its accuracy and effectiveness.Results:As the surgical difficulty increased (groups 1, 2, and 3), the postoperative drainage tube duration was correspondingly prolonged [(5.92±1.48) d, (8.00±1.75) d, and (11.88±4.45) d, respectively, P<0.05], and the severity of postoperative complications also significantly increased (the incidence of Clavien-Dindo grade ≥2 was 5.66%, 31.82% and 64.00%, respectively, P<0.01). In the analysis of rate-limiting steps, the time taken for all steps, except for Trocar placement, showed significant differences among the difficulty subgroups ( P<0.001). However, the average time for renal hilar dissection was (19.82±5.65) min, which was significantly longer than the other steps ( P<0.001). Therefore, renal hilar dissection was identified as the rate-limiting step of hand-assisted laparoscopic donor nephrectomy. In terms of the influencing factors of surgical difficulty, donor obesity, kidney width, abdominal anteroposterior sagittal diameter, number of renal arteries, distance from renal artery bifurcation to the abdominal aorta, degree of renal artery calcification, and mayo adhesive probability (MAP) score were all correlated with the surgical difficulty score ( P<0.05). However, multiple linear regression analysis revealed that only the number of renal arteries and the MAP score were the independent risk factors for higher surgical difficulty of hand-assisted laparoscopic donor nephrectomy. The predictive equation was: surgical difficulty=0.649×number of renal arteries+ 0.770×MAP score. Both internal and external validation confirmed the model's good accuracy. Conclusions:This study established a reliable and objective predictive model for the difficulty of hand-assisted laparoscopic donor nephrectomy based on the number of renal arteries and the MAP score. Renal hilar dissection was identified as the rate-limiting step of the procedure. This provides a reference for selecting an appropriate surgeon based on the predicted surgical difficulty.

Objective:To compare the effectiveness, safety and postoperative recurrence of percutaneous nephrolithotomy (PCNL) with Holmium laser for upper urinary calculi in Uyghur and Han pediatric patients.Methods:The data of 123 Uyghur and 71 Han pediatric patients with upper urinary calculi admitted to First People's Hospital of Kashgar, Xinjiang and Beijing Friendship Hospital, Capital Medical University respectively, from August 2018 to August 2023, were retrospectively reviewed. The gender [males 73 (59.3%) vs.46 (64.8%) ], laterality (single/bilateral: 94/29 vs. 59/12), hydronephrosis [115 (93.5%) vs. 63 (88.7%)] and anatomical abnormalities [2(1.6%) vs. 5(7.0%)] of Uyghur and Han children were not statistically significant ( P>0.05). Uyghur children were older than Han children [5 (3, 7) vs. 3 (2, 6) years old], with a higher proportion of emaciated children [27 (21.9%) vs. 6 (8.5%) cases], a larger maximum stone diameter [(2.30±0.78) vs. (1.96±1.50) cm] and a lower proportion of multiple stones [46 (37.4%) vs. 52 (73.2%) cases] (all P<0.05). All the patients were treated with Holmium laser PCNL. The channels of the procedures in this study include F12-18 small channels and visual puncture channels. The operation datas, stone-free rate (SFR), complication rate (CR) and stone recurrence rate of the two groups were compared. Meanwhile, multiple logistic regression analysis was used to explore the factors influencing these indicators. Results:The operation time for Uyghur children was significantly longer than that of Han children [75.0 (58.0, 93.0) vs. 30.0 (20.0, 48.8) min]. Additionally, a greater proportion of Uyghur children underwent PCNL with F12-18 small channels than Han children [119 (96.7%) vs. 49(69.0%) cases]. The SFR [89.4%(110/123)vs.88.7%(63/71)], and postoperative CR [31.7%(39/123)vs. 26.8%(19/71)] in Uyghur and Han patients were not significantly different (all P>0.05). The recurrence rate in Uyghur children was higher than that observed in Han children [28.1%(25/89) vs. 15.6%(10/64), P=0.033]. The multivariate logistic regression analysis results indicated that the maximum stone diameter was an independent risk factor for SFR in both groups ( OR=0.401, 95% CI 0.191-0.842, P=0.016). Similarly, maximum stone diameter ( OR=1.896, 95% CI 1.088-3.304, P=0.024) and multiple stones ( OR=3.225, 95% CI 1.409-7.384, P=0.024) were identified as independent risk factors for CR. Ethnicity was not independent risk factor for SFR( OR=0.679, 95% CI 0.215-2.140), CR( OR=1.047, 95% CI 0.495-2.215) and stone recurrence rate( OR=0.820, 95% CI 0.285-2.356, all P>0.05). Conclusions:In comparison to Han pediatric patients during the same period, Holmium laser PCNL had similar SFR and CR for treating Uyghur children with upper urinary calculi, who were older, more emaciated and had larger average stone diameters. The higher postoperative recurrence rate of Uyghur children is likely to be associated with higher stone burden. The multivariate logistic regression analysis results showed that ethnicity was not an influential factor in SFR, complication rates, and stone recurrence rates. The findings need to be further validated in larger prospective cohort studies.

BACKGROUND: Bone tissue engineering plays a very important role in the repair of bone defects, which can deliver bioactive substances, promote bone tissue growth and repair bone defects. Bone scaffolds act as one of the three elements of bone tissue engineering. Three-dimensional (3D) printing technology can achieve individualized bone tissue repair through customized artificial bone preparation.OBJECTIVE: To analyze the biological characteristics of several commonly used bone tissue engineering scaffolds and to explore the application of 3D printing technique in the construction of bone tissue engineering scaffolds.METHODS: The literatures of PubMed and Wanfang database related to bone tissue engineering scaffold materials and 3D printing technology were retrieved from 2005 to 2016. The Keywords were tissue engineering scaffold, bone defects,polymer materials, bioceramics, metal materials, composite materials, 3D printing in English and Chinese, respectively,which would appear simultaneously in title and abstract. Repetitive articles were excluded and finally 65 articles were included in result analysis.RESULTS AND CONCLUSION: The commonly used bone tissue engineering scaffold materials include polymer materials (natural and macromolecule polymeric materials), bioceramics, and metal materials. According to the characteristics of the materials, composite materials made of different materials can compensate for the shortcomings of a single material, and then developed into new tissue engineering scaffold materials. For the tissue engineering bone production, 3D printing technologies include melt deposition technology, selective laser sintering technology, low temperature deposition manufacturing technology, and etc. When the 3D printing technology is used to prepare a bone tissue engineering scaffold, the use of powder or adhesive must have limited conditions, such as flowability, stability and wettability. Powder materials used for 3D printing can be divided into synthetic polymers, natural macromolecules,bioceramics and their mixtures, with different advantages and disadvantages. Ultimately, the bone engineering scaffolds produced by 3D printing technology have unique advantages in mechanics, structure and individuality, and have wide application prospect in the manufacture of bone scaffolds.