[Clinical research of multisystem inflammatory syndrome in children]

Objective: To analyze the clinical characteristics of children with multisystem inflammatory syndrome (MIS-C) associated with SARS-CoV-2 in China, and to improve the understanding of MIS-C among pediatricians. Methods: Case series study.Collect the clinical characteristics, auxiliary examinations, treatment decisions, and prognosis of 64 patients with MIS-C from 9 hospitals in China from December 2022 to June 2023. Results: Among the 64 MIS-C patients, 36 were boys and 28 were girls, with an onset age being 2.8 (0.3, 14.0) years. All patients suffered from fever, elevated inflammatory indicators, and multiple system involvement. Forty-three patients (67%) were involved in more than 3 systems simultaneously, including skin mucosa 60 cases (94%), blood system 52 cases (89%), circulatory system 54 cases (84%), digestive system 48 cases (75%), and nervous system 24 cases (37%). Common mucocutaneous lesions included rash 54 cases (84%) and conjunctival congestion and (or) lip flushing 45 cases (70%). Hematological abnormalities consisted of coagulation dysfunction 48 cases (75%), thrombocytopenia 9 cases (14%), and lymphopenia 8 cases (13%). Cardiovascular lesions mainly affected cardiac function, of which 11 patients (17%) were accompanied by hypotension or shock, and 7 patients (12%) had coronary artery dilatation.Thirty-six patients (56%) had gastrointestinal symptoms, 23 patients (36%) had neurological symptoms. Forty-five patients (70%) received the initial treatment of intravenous immunoglobulin in combination with glucocorticoids, 5 patients (8%) received the methylprednisolone pulse therapy and 2 patients (3%) treated with biological agents, 7 patients with coronary artery dilation all returned to normal within 6 months. Conclusions: MIS-C patients are mainly characterized by fever, high inflammatory response, and multiple organ damage. The preferred initial treatment is intravenous immunoglobulin combined with glucocorticoids. All patients have a good prognosis.

[Clinical analysis of 10 cases of multi-center tumor necrosis factor receptor-associated periodic syndrome]

Objective: To summarize the clinical characteristics of tumour necrosis factor receptor-associated periodic syndrome (TRAPS) in children. Methods: The clinical manifestations, laboratory tests, genetic testing and follow-up of 10 children with TRAPS from May 2011 to May 2021 in 6 hospitals in China were retrospectively analyzed. Results: Among the 10 patients with TRAPS, including 8 boys and 2 girls. The age of onset was 2 (1, 5) years, the age of diagnosis was (8±4) years, and the time from onset to diagnosis was 3 (1, 7) years. A total of 7 types of TNFRSF1A gene variants were detected, including 5 paternal variations, 1 maternal variation and 4 de novo variations. Six children had a family history of related diseases. Clinical manifestations included recurrent fever in 10 cases, rash in 4 cases, abdominal pain in 6 cases, joint involvement in 6 cases, periorbital edema in 1 case, and myalgia in 4 cases. Two patients had hematological system involvement. The erythrocyte sedimentation rate and C-reactive protein were significantly increased in 10 cases. All patients were negative for autoantibodies. In the course of treatment, 5 cases were treated with glucocorticoids, 7 cases with immunosuppressants, and 7 cases with biological agents. Conclusions: TRAPS is clinically characterized by recurrent fever accompanied by joint, gastrointestinal, skin, and muscle involvement. Inflammatory markers are elevated, and autoantibodies are mostly negative. Treatment mainly involves glucocorticoids, immunosuppressants, and biological agents.

Identifying the optimal deep learning architecture and parameters for automatic beam aperture definition in 3D radiotherapy

PURPOSE

Two-dimensional radiotherapy is often used to treat cervical cancer in low- and middle-income countries, but treatment planning can be challenging and time-consuming. Neural networks offer the potential to greatly decrease planning time through automation, but the impact of the wide range of hyperparameters to be set during training on model accuracy has not been exhaustively investigated. In the current study, we evaluated the effect of several convolutional neural network architectures and hyperparameters on 2D radiotherapy treatment field delineation.

METHODS

Six commonly used deep learning architectures were trained to delineate four-field box apertures on digitally reconstructed radiographs for cervical cancer radiotherapy. A comprehensive search of optimal hyperparameters for all models was conducted by varying the initial learning rate, image normalization methods, and (when appropriate) convolutional kernel size, the number of learnable parameters via network depth and the number of feature maps per convolution, and nonlinear activation functions. This yielded over 1700 unique models, which were all trained until performance converged and then tested on a separate dataset.

RESULTS

Of all hyperparameters, the choice of initial learning rate was most consistently significant for improved performance on the test set, with all top-performing models using learning rates of 0.0001. The optimal image normalization was not consistent across architectures. High overlap (mean Dice similarity coefficient = 0.98) and surface distance agreement (mean surface distance < 2 mm) were achieved between the treatment field apertures for all architectures using the identified best hyperparameters. Overlap Dice similarity coefficient (DSC) and distance metrics (mean surface distance and Hausdorff distance) indicated that DeepLabv3+ and D-LinkNet architectures were least sensitive to initial hyperparameter selection.

CONCLUSION

DeepLabv3+ and D-LinkNet are most robust to initial hyperparameter selection. Learning rate, nonlinear activation function, and kernel size are also important hyperparameters for improving performance.

[Prognostic comparison of active surveillance and adjuvant chemotherapy in the treatment of patients with stage Ⅰ ovarian immature teratoma after fertility-sparing surgery]

Objective: To compare the survival outcomes between surveillance and adjuvant chemotherapy in patients with stage Ⅰ ovarian immature teratoma (IMT) underwent fertility-sparing surgery. Methods: Clinical and pathological records of patients with stage Ⅰ ovarian IMT between Jan. 2011 to Feb. 2023 were collected from Peking Union Medical College Hospital, except stage Ⅰa grade 1. The consultation of risks and benefits regarding adjuvant chemotherapy was conducted by gynecologic oncologists. A shared decision about surveillance or chemotherapy was made by physician and patients or their guardians. Patients who finally decided to undergo surveillance were included in the surveillance group (n=40), the others were included in the adjuvant chemotherapy group (n=63). Clinical characteristics, treatment and survival outcomes were analyzed and compared between two groups. Results: A total of 103 patients were included. The median age of initial diagnosis was 20 years old (range: 3-39 years old), and the median follow-up time was 31 months (range: 1-254 months). The age, International Federation of Gynecology and Obstetrics (FIGO) stage, pathological grade, surgical method, and preoperative and postoperative alpha-fetoprotein levels in the surveillance group and the adjuvant chemotherapy group were similar (all P>0.05). The surgical approach and maximum tumor diameter between two groups were significantly different (all P<0.05). Forty patients of the surveillance group were identified, only one patient with stage Ⅰa grade 2 IMT who underwent cystectomy had malignant recurrence on the same ovary. Another 63 patients received adjuvant chemotherapy after surgery, five patients had malignant recurrence, and two of them died of disease progression after relapsed. There were no significant differences in disease-free survival (DFS;20 vs 36 months) and overall survival (OS; 23 vs 39 months) between the surveillance group and the adjuvant chemotherapy group (follow-up time censored at 72 months; DFS: P=0.325, OS: P=0.278). Conclusions: There are no differences in survival outcomes between patients with stage Ⅰ ovarian IMT underwent adjuvant chemotherapy or not. Active surveillance might be safe and preferable in stage Ⅰ IMT patients underwent complete resection of tumor.

[Clinical study of mature B-cell lymphoma in 11 children with chromosome 11 long-arm abnormalities]

Objective: To explore the clinical, pathological, diagnostic, treatment, and prognostic features of children with mature B-cell lymphoma (MBCL) . Methods: This retrospective study included pediatric patients with MBCL with chromosome 11 long-arm abnormalities who were diagnosed and treated at our hospital from December 2018 to February 2023. Results: Among the 11 pediatric patients with MBCL, nine were male and two were female, with a median age of 9 (2-13) years and a median disease course of 1.8 (0.5-24) months. The clinical manifestations were cervical lymph node enlargement in four patients, nasal congestion and snoring in four patients, abdominal pain in two patients, and difficulty breathing in one patient. There were seven cases of Burkitt's lymphoma, two of follicular lymphoma, and two of advanced B-cell lymphoma according to the pathological morphology examination. No patients had central nervous system or bone marrow involvement, and no extensive metastasis was observed on B-ultrasound or positron emission tomography-computed tomography (PET/CT). One patient had a huge tumor lesion. The Revised International Pediatric Non-Hodgkin Lymphoma Staging System classified four patients as stage Ⅱ, five as stage Ⅲ, and two as stage Ⅳ. 11q probe detection showed five cases of 11q gain, three of 11q loss, and three of both gain and loss. FISH showed positive MYC expression in three patients, including eight with advanced B-cell lymphoma with 11q abnormalities and three with Burkitt's lymphoma with 11q abnormalities. According to the 2019 edition of the National Health Commission's diagnostic and treatment guidelines for invasive MBCL in children, one patient was classified as Group A, two as Group B, and eight as Group C. Early evaluation of the efficacy showed complete remission. After mid-term evaluation, the intensity of chemotherapy was reduced in Group B and Group C. Among two cases of chemotherapy, the remaining nine cases had a median follow-up of 32 (6-45) months, and none had event-related survival. Conclusion: The incidence of MBCL with 11q abnormalities in children is low, clinical symptoms are mild, and progression is slow. The absence of MYC, BCL2, BCL6 rearrangements, C-MYC negative and 11q abnormalities on FISH is an important diagnostic indicator, and reducing the intensity of chemotherapy can improve prognosis.

[Analysis on the implementation of payment policies for four non-national immunization program vaccines in China]

This study systematically retrieved information on the payment policy of vaccination fees for pneumococcal vaccines, human papillomavirus vaccines, haemophilus influenzae type b vaccines and rotavirus vaccines using a Python-based crawler. The proportion of the population covered by policies among the total applicable population was estimated based on the medical insurance coverage ratio and population data in 2020. This study showed that the payment policies included two categories, government-funded free vaccination policies and medical insurance payment policies. Among the four non-national immunization program vaccines, the free vaccination policies only involved pneumococcal vaccines and human papillomavirus vaccines. Among them, the 13-valent pneumococcal conjugate vaccine, the 23-valent pneumococcal polysaccharide vaccine, and the human papillomavirus vaccine were provided free of charge in 1, 10 and 15 provinces, respectively. For these policies, the corresponding covered population and the proportion among the total applicable population were children aged 6 months to 2 years old (2.5%), older people (1.2% to 21.5%) and middle school girls (1.1% to 12.2%). Medical insurance payment policies were implemented in 14 provinces, and nearly covered the four types of vaccines in the policy implementation areas, with the proportion of the covered population about 10.9% to 41.5% among the total applicable population.

[Analysis of clinical presentation and genetic characteristics of malignant infantile osteopetrosis]

Objective: To investigate the clinical presentation and genetic characteristics of malignant infantile osteopetrosis. Methods: This was a retrospective case study. Thirty-seven children with malignant infantile osteopetrosis admitted into Beijing Children's Hospital from January 2013 to September 2022 were enrolled in this study. According to the gene mutations, the patients were divided into the CLCN7 group and the TCIRG1 group. Clinical characteristics, laboratory tests, and prognosis were compared between two groups. Wilcoxon test or Fisher exact test were used in inter-group comparison. The survival rate was estimated with the Kaplan-Meier method and the Log-Rank test was used to compare the difference in survival between groups. Results: Among the 37 cases, there were 22 males and 15 females. The age of diagnosis was 0.5 (0.2, 1.0) year. There were 13 patients (35%) and 24 patients (65%) with mutations in CLCN7 and TCIRGI gene respectively. Patients in the CLCN7 group had an older age of diagnosis than those in the TCIRGI group (1.2 (0.4, 3.6) vs. 0.4 (0.2, 0.6) years, Z=-2.60, P=0.008). The levels of serum phosphorus (1.7 (1.3, 1.8) vs. 1.1 (0.8, 1.6) mmol/L, Z=-2.59, P=0.010), creatine kinase isoenzyme (CK-MB) (457 (143, 610) vs. 56 (37, 82) U/L, Z=-3.38, P=0.001) and the level of neutrophils (14.0 (9.9, 18.1) vs. 9.2 (6.7, 11.1) ×109/L, Z=-2.07, P=0.039) at diagnosis were higher in the CLCN7 group than that in the TCIRG1 group. However, the level of D-dimer in the CLCN7 group was lower than that in the TCIRGI group (2.7 (1.0, 3.1) vs. 6.3 (2.5, 9.7) μg/L, Z=2.83, P=0.005). After hematopoietic stem cell transplantation, there was no significant difference in 5-year overall survival rate between the two groups (92.3%±7.4% vs. 83.3%±7.6%, χ²=0.56, P=0.456). Conclusions: TCIRGI gene mutations are more common in children with osteopetrosis. Children with TCIRGI gene mutations have younger age, lower levels of phosphorus, CK-MB, and neutrophils and higher level of D-dimer at the onset. After hematopoietic stem cell transplantation, patients with CLCN7 or TCIRGI gene mutations have similar prognosis.

Optimal biopsy site for the diagnosis of oral pemphigus vulgaris and mucous membrane pemphigoid: a systematic review and meta-analysis

The aim of this study was to critically evaluate the diagnostic yields of direct immunofluorescence (DIF) analysis on perilesional and normal-appearing mucosa biopsy samples, to determine the optimal biopsy site for patients presenting with oral pemphigus vulgaris (PV) or mucous membrane pemphigoid (MMP). Electronic databases and article bibliographies were searched in December 2022. The primary outcome was the rate of DIF positivity. Of 374 records identified after the elimination of duplicates, 21 studies with 1027 samples were ultimately included. Meta-analysis revealed a pooled DIF positivity rate of 99.6% (95% confidence interval (CI) 97.4-100.0%, I2 = 0%) for PV and 92.6% (95% CI 87.9-96.5%, I2 = 44%) for MMP for biopsies from perilesional sites, and of 95.4% (95% CI 88.6-99.5%, I2 = 0%) for PV and 94.1% (95% CI 86.5-99.2%, I2 = 42%) for MMP for biopsies from normal-appearing sites. For MMP, there was no significant difference in the rate of DIF positivity between the two biopsy sites (odds ratio 1.91, 95% CI 0.91-4.01, I2 = 0%). The results suggest that the perilesional mucosa remains the optimal biopsy site for DIF diagnosis of oral PV, while the normal-appearing mucosa biopsy is optimal for oral MMP.

[Association of category of dietary intake and physical activity with the risk of mortality in patients with type 2 diabetes mellitus: a prospective cohort study]

Objective: To investigate the association between dietary intake and physical activity category and their combined effects on all-cause and cause-specific mortality risk in patients with type 2 diabetes mellitus (T2DM). Methods: Between December 2013 and December 2021, a prospective cohort study was conducted on 19 863 T2DM patients in Changshu City, Qingjiangpu District (formerly Qinghe District), and Huai'an District, included in the national basic health service management. Information on deaths and underlying causes of death was obtained from the Jiangsu Provincial CDC and Prevention Death Surveillance System. Cox proportional hazards models were used to estimate the intensity of associations between dietary intake, physical activity, and their combined effects with all-cause and cause-specific mortality in patients with T2DM. Results: As of December 31, 2021, the research subjects had been followed up for 150 283 person-years, with a median follow-up time of 8.15 years. During the follow-up period, 3 293 people died, including 1 124 deaths from cardiovascular disease (CVD) and 875 deaths from cancer. Cox regression analysis showed that compared with the population of 0-1 recommended food group, those having more than five recommended food groups had a 19% lower risk of all-cause mortality [hazard ratio (HR)=0.81, 95%CI: 0.70-0.94] and a 33% lower risk of all-cause mortality (HR=0.67, 95%CI: 0.52-0.87). Compared with the T2DM population in the physical activity Q1 group, the risk of all-cause mortality, CVD mortality, and cancer mortality among the physical activity Q4 group reduced by 50% (HR=0.50, 95%CI: 0.45-0.56), 50% (HR=0.50, 95%CI: 0.41-0.61), and 27% (HR=0.73, 95%CI: 0.60-0.88), respectively. The combined effect showed that compared with the population in the intake of food categories 0-2 and low physical activity groups, the risk of all-cause, CVD mortality, and cancer mortality in the intake of food categories 4-9 and high physical activity groups reduced by 55% (HR=0.45, 95%CI: 0.38-0.53), 56% (HR=0.44, 95%CI: 0.32-0.59), and 40% (HR=0.60, 95%CI: 0.44-0.82), respectively. Conclusion: Type of dietary intake, physical activity, and their combined effects are associated with a reduced mortality risk in patients with T2DM.

Radiation Planning Assistant - A Web-based Tool to Support High-quality Radiotherapy in Clinics with Limited Resources

Access to radiotherapy worldwide is limited. The Radiation Planning Assistant (RPA) is a fully automated, web-based tool that is being developed to offer fully automated radiotherapy treatment planning tools to clinics with limited resources. The goal is to help clinical teams scale their efforts, thus reaching more patients with cancer. The user connects to the RPA via a webpage, completes a Service Request (prescription and information about the radiotherapy targets), and uploads the patient's CT image set. The RPA offers two approaches to automated planning. In one-step planning, the system uses the Service Request and CT scan to automatically generate the necessary contours and treatment plan. In two-step planning, the user reviews and edits the automatically generated contours before the RPA continues to generate a volume-modulated arc therapy plan. The final plan is downloaded from the RPA website and imported into the user's local treatment planning system, where the dose is recalculated for the locally commissioned linac; if necessary, the plan is edited prior to approval for clinical use.

[Clinical characteristics of children with SARS-CoV-2 Omicron variant infection in Kunming]

Objective: To investigate the clinical characteristics of hospitalized children infected with the Omicron variant in Kunming after the withdrawal of non-pharmaceutical interventions (NPI) and analyze the risk factors of severe cases. Methods: Clinical data was retrospectively collected from 1 145 children with SARS-CoV-2 Omicron infection who were hospitalized in six tertiary grade A hospitals in Kunming from December 10th, 2022 to January 9th, 2023. According to clinical severity, these patients were divided into the general and severe SARS-CoV-2 groups, and their clinical and laboratory data were compared. Between-group comparison was performed using t-test, chi-square test and Mann-Whitney U test. Spearman correlation test and multivariate Logistic regression analysis were used to determine the risk factors of severe illness. Results: A total of 1 145 hospitalized patients were included, of whom 677 were male and 468 female. The age of these patients at visit was 1.7 (0.5, 4.1) years. Specifically, there were 758 patients (66.2%) aged ≤3 years at visit and 387 patients (33.8%) aged >3 years. Of these children, 89 cases (7.8%) had underline diseases and the remaining 1 056 cases (92.2%) had no combined diseases. Additionally, of all the patients, 319 cases (27.9%) were vaccinated with one or two doses of SARS-CoV-2 vaccine, 748 cases (65.3%) had acute upper respiratory tract infection (AURTI), and six cases died (0.5%). A total of 1 051 cases (91.8%) were grouped into general SARS-CoV-2 group and 94 cases (8.2%) were grouped into severe SARS-CoV-2 group. Compared with the general cases, the severe cases showed a lower rate of SARS-CoV-2 vaccination and younger median age, lower lymphocyte count, as well as proportions of CD8+T lymphocyte (36 cases (38.3%) vs. 283 cases (26.9%), 0.5 (2.6, 8.0) vs. 1.6 (0.5, 3.9) years, 1.3 (1.0, 2.7) ×109 vs. 2.7 (1.3,4.4)×109/L, 0.17 (0.12, 0.24) vs. 0.21 (0.15, 0.16), respectively, χ2=4.88, Z=-2.21,-5.03,-2.53, all P<0.05). On the other hand, the length of hospital stay, proportion of underline diseases, ALT, AST, creatine kinase isoenzyme, and troponin T were higher in the severe group compared to those in the general group ((11.6±5.9) vs. (5.3±1.8) d, 41 cases (43.6%) vs. 48 cases (4.6%), 67 (26,120) vs. 20 (15, 32) U/L, 51 (33, 123) vs. 44 (34, 58) U/L、56.9 (23.0, 219.3) vs. 3.6 (1.9, 17.9) U/L, 12.0 (4.9, 56.5) vs. 3.0 (3.0, 7.0) ×10-3 pg/L,respectively, t=-20.43, χ2=183.52, Z=-9.14,-3.12,-6.38,-3.81, all P<0.05). Multivariate regression analysis indicated that increased leukocyte count (OR=1.88, 95%CI 1.18-2.97, P<0.01), CRP (OR=1.18, 95%CI 1.06-1.31, P<0.01), ferritin (OR=1.01, 95%CI 1.00-1.00, P<0.01), interleukin (IL)-6 (OR=1.05, 95%CI 1.01-1.08, P=0.012), D-dimer (OR=2.56, 95%CI 1.44-4.56, P<0.01) and decreased CD4+T lymphocyte (OR=0.84, 95%CI 0.73-0.98, P=0.030) were independently associated with the risk of severe SARS-CoV-2 in hospitalized children with Omicron infection. Conclusions: After the withdrawal of NPI, the pediatric inpatients with Omicron infection in Kunming were predominantly children younger than 3 years of age, and mainly manifested as AURTI with relatively low rate of severe SARS-CoV-2 infection and mortality. Elevated leukocyte counts, CRP, ferritin, IL-6, D-dimer, and decreased CD4+T lymphocytes are significant risk factors for developing severe SARS-CoV-2 infection.

Long-Term Outcomes of Stereotactic Body Radiation Therapy with or without PD-1 Inhibitors in Metastatic Nasopharyngeal Carcinoma

PURPOSE/OBJECTIVE(S)

Data on the benefit of stereotactic body radiation therapy (SBRT) in patients with metastatic nasopharyngeal carcinoma (mNPC) remain limited. The purpose of this study is to assess the outcomes of mNPC treated with SBRT and programmed death-ligand 1 (PD-1) inhibitors.

MATERIALS/METHODS

We reviewed all SBRT performed in patients with mNPC during the period of 2013-2022 in our institution. Treatments carried out with ablative intent in stereotactic conditions with dose/fraction ≥ 5 Gy were considered. The local control (LC), overall survival (OS), and progression-free survival (PFS) rates were calculated using Kaplan-Meier analyses. Risk factors were assessed through univariate and multivariate analysis by Cox regression.

RESULTS

A total of 55 patients with 77 metastatic lesions treated with SBRT were analyzed. All of these patients received systemic treatment, either chemotherapy alone (n = 34) or chemotherapy with PD-1 inhibitors (n = 21). 28 patients (50.9%) had ≤ five metastatic lesions in the metastatic sites. The number of irradiated tumors ranged from 1 to 6, and 36 patients (65.5%) with 47 lesions received a physical dose ≥48 Gy (BED≥75Gy, α/β = 10). After a median follow-up of 43.6 months (range 1.9-115.3 months), 20 patients (36.4%) experienced local recurrence after completion of SBRT for metastatic lesions. The 1- and 3-year LC rates were 76.9% and 61.9%, respectively. The 1- and 3-year OS rates were 84.4% and 58.2%, and the 1- and 3-year PFS rates were 50.0% and 29.9%, respectively. Patients with ≤ 2 metastatic lesions (n = 24, 43.6%) had significant better LC (HR 0.11, 95% CI 0.036-0.313, p<0.001), OS (HR 0.24, 95% CI 0.08-0.74, p = 0.013) and PFS (HR 0.16, 95% CI 0.063-0.42, p<0.001) than patients with>2 metastatic lesions. Total dose≥48 Gy was also found to be a significant prognostic factor for better OS (HR 0.44, 95% CI 0.18-1.09, p = 0.044) and PFS (HR 0.42, 95% CI 0.17-0.88, p = 0.005), but not LC (HR 0.84, 95% CI 0.36-1.97, p = 0.678). In addition, adding PD-1 inhibitors to SBRT showed a significant benefit, improving the 2-year LC to 87.7% vs. 50.6% for SBRT (HR 0.27, 95% CI 0.18 - 0.41, p = 0.002). No patients experienced grade 4 or 5 toxicity.

CONCLUSION

SBRT is an effective and safe treatment option for mNPC patients. Adding PD-1 inhibitors to SBRT offers a benefit in LC. Additional studies exploring the clinical benefit and predictive biomarkers of combined SBRT and PD-1 directed immunotherapy are warranted.

A Cascaded Deep Learning-Based Cardiac Substructures Segmentation Frame and on Non-Gated Non-Enhanced Planning CT Scans in Breast Cancer Patients

PURPOSE/OBJECTIVE(S)

To develop a deep learning-based segmentation frame for cardiac substructures especially coronary arteries (CAs) on non-gated non-enhanced planning computed tomography (CT) scans in breast cancer (BC) patients.

MATERIALS/METHODS

Non-gated non-enhanced CT scans of 39 BC patients receiving adjuvant radiotherapy (RT) were collected. Cardiac substructures were manually labelled, including four chambers, left main (LM), left anterior descending (LAD), left circumflex (LCX) and right coronary artery (RCA). The training, validation, and test sample is 28, 7 and 4, respectively. A cascaded network, using nnUNet as the backbone, is proposed to use chambers as prior information to constrain the segmentation of CAs. The mean Dice similarity coefficient (DSC), 95th percentile Hausdorff distance (HD95) and average symmetrical surface distance (ASSD) were used as geometric metrics. Dosimetric parameters of cardiac substructures was calculated based on the segmentation frame and manually labeled contouring, respectively. The data of cardiac examination including ultrasonography, electrocardiogram before and during the follow-up after RT were retrospectively collected. The cardiac event was any symptomatic heart disease or new-onset abnormality in the cardiac examination after RT.

RESULTS

The mean DSC of heart, atriums and ventricles of the proposed frame was 0.93, 0.90, and 0.93, respectively. As shown in Table 1, compared with direct segmentation (as baseline), the proposed frame had a better performance in terms of HD95, ASSD, and the mean dose (Dmean) absolute error for all CAs. Compared to the dosimetric parameters of the heart collected based on the manual labelled contours, the relative errors of D5, D95, and V15Gy for LAD was 4.3±7.8%, 11.7±5.9%, and 14.6±13.0% collected based on the direct segmentation contours and 2.4±4.4%, 3.9±3.1%, 8.5±6.9% collected based on the auto-segmented contours, respectively. Multivariate analysis showed that increased V15Gy of LAD was an independent cardiac toxicity risk factor ([HR] = 1.07, 95% CI 1-1.15, p = 0.0387).

CONCLUSION

We developed a cascaded network for cardiac substructures segmentation with dosimetric validation on non-enhanced CT scans in breast cancer radiotherapy. This is the first attempt to use chambers as prior information for CAs' segmentation and had a superior stable performance. Accurate segmentation will help radiation oncologists to better evaluate DVHs based on substructures and thus to estimate cardiovascular risk. An optimized cardiac substructure-based dosimetric constrain may be proposed accordingly.

High Dose Hyperfractionated Thoracic Radiotherapy vs. Standard Dose for Limited Stage Small-Cell Lung Cancer: A Multicenter, Open-Label Randomized, Phase 3 Trial

PURPOSE/OBJECTIVE(S)

Limited stage small-cell lung cancer (LS-SCLC) is associated with poor prognosis. We aimed to assess the efficacy and safety of high-dose, hyperfractionated thoracic radiotherapy of 54 Gy in 30 fractions compared with standard dose (45 Gy in 30 fractions) as a first-line treatment for LS-SCLC.

MATERIALS/METHODS

The study was an open-label, randomized, phase 3 trial, done at 16 public hospitals in China. Key inclusion criteria were patients aged 18-70 years, with previously histologically or cytologically confirmed LS-SCLC, previously untreated or received 1-2 courses of intravenous cisplatin (75 mg/m²of body-surface area, on day 1 or divided into two days of each cycle) or carboplatin (area under the curve of 5 mg/mL per min, day 1 of each cycle)and intravenous etoposide (100 mg/m²of body-surface area, on days 1-3 of each cycle), and an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1.Eligible patients were randomly assigned (1:1) to receive volumetric-modulated arc radiotherapy (VMAT) of 45 Gy in 30 fractions or the simultaneous integrated boost VMAT (SIB-VMAT) of 54 Gy in 30 fractions to the primary lung tumor and lymph node metastases starting 0-42 days after the first chemotherapy course. Both groups of patients received thoracic radiotherapy twice per day and 10 fractions per week. Prophylactic cranial radiation (PCI, 25 Gy in 10 fractions) was implemented to patients with responsive disease. The primary endpoint was overall survival. Safety was analyzed in the as-treated population.

RESULTS

Between June 30, 2017, and April 6, 2021, 224 eligible patients were enrolled and randomly assigned to 54 Gy (n = 108) or 45 Gy (n = 116). Median follow-up for the primary analysis was 45 months (IQR 41-48). Median overall survival was significantly improved in the 54 Gy group (62.4 months) compared with the 45 Gy group (43.1 months; p = 0.001). Median progression-free survival was significantly improved in the 54 Gy group (30.5 months) compared with the 45 Gy group (16.7 months; p = 0.044). The most common grade 3-4 adverse events were neutropenia (30 [28%] of 108 patients in the 54 Gy group vs 27 [23%] of 116 patients in the 45 Gy group), neutropenic infections (6 [6%] vs 2 [2%]), thrombocytopenia (13 [12%] vs 12 [10%]), anemia (6 [6%] vs 4 [3%]), and esophagitis (1 [1%] vs 3 [3%]). Treatment-related serious adverse events occurred in 9 [8%] patients in the 54 Gy group and 16 [14%] patients in the 45 Gy group. There were one treatment-related deaths in 54 Gy group (myocardial infarction).

CONCLUSION

Compared with standard thoracic radiotherapy dose of 45 Gy, the high dose of 54 Gy improved overall survival and progression-free survival without increasing toxicities in patients with LS-SCLC, supporting twice-daily hyperfractionated thoracic radiotherapy of 54 Gy with concurrent chemotherapy is an alternative treatment option for LS-SCLC. This study is complete and registered with ClinicalTrials.gov, NCT03214003.

Effect of Anemia on Tumor Response to Preoperative Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer

PURPOSE/OBJECTIVE(S)

Preoperative neoadjuvant chemoradiotherapy (nCRT) and total rectal mesenteric resection (TME) are the primary treatment options for locally advanced rectal cancer (LARC), but their efficacy varies. This study aimed to investigate the impact of anemia on the tumor response of patients with LARC receiving preoperative neoadjuvant chemoradiotherapy.

MATERIALS/METHODS

This study was a retrospective analysis of clinical and pathological data from patients with LARC who underwent nCRT and TME from January 2019 to May 2022 at a single institution. The tumor response was evaluated based on the tumor regression grade (TRG) and T-stage change of the primary tumor. Hemoglobin concentration was measured and graded to determine the presence of anemia. Anemia was categorized into four groups based on the hemoglobin levels: mild anemia (90-120 g/L), moderate anemia (60-90 g/L), severe anemia (30-60 g/L), and extreme anemia (less than 30 g/L). Finally, tumor response was quantified histologically using the AJCC 8th edition tumor regression grading system for rectal cancer and pre- and post-treatment T-grading.

RESULTS

A total of 88 patients with LARC who received nCRT and TME were included in the study, with 17 females and 71 males. Of these patients, 9 were moderately anemic and 37 were mildly anemic. The radiation therapy regimen was administered at a dose of 1.8-2 Gy per fraction, five times a week, for a total dose of 45-50.4 Gy. Capecitabine chemotherapy was also administered orally (825 mg/m2, twice a day) on the days of radiation therapy. Other chemotherapy regimens included XELOX and mFOLFOX6. The TRG was significantly different in anemic patients compared to non-anemic patients (P = 0.039). Only 2 out of 46 anemic patients (4%) showed an excellent response (TRG0), while 8 out of 42 non-anemic patients (19%) showed an excellent response (p = 0.043). There was also a significant difference in the incidence of anemia between cT3 and cT4 stages (p = 0.048), with 44% of cT3 patients and 67% of cT4 patients being anemic. The number of patients with poor response (TRG2-3) decreased as the degree of anemia decreased, but no significant difference was found. The incidence of TRG3 was 11% in patients with moderate anemia and 7% in non-anemic patients (P = 0.863). There was no significant difference in postoperative pathological T-stage between anemic and non-anemic patients. 89% of anemic patients had a pathological stage of ypT3 or less after chemoradiotherapy, while 95% of non-anemic patients did (P = 0.167). The pre- and post-treatment pathological staging did not significantly differ between anemic and non-anemic patients. 67% of anemic patients had descending tumors, while 59.5% of non-anemic patients had descending tumors (p = 0.509).

CONCLUSION

Patients with LARC who have normal hemoglobin concentrations during nCRT have better tumor regression compared to patients with anemia. Additionally, the incidence of anemia was higher among patients with advanced T-stage prior to treatment.

Does Dual Anti-HER2 Therapy Increase Early Cardiac Toxicity in Comparison with Trastuzumab Alone in Breast Cancer Patients Receiving Adjuvant Radiotherapy? A Multicenter Retrospective Study

PURPOSE/OBJECTIVE(S)

Adjuvant trastuzumab in combination with RT has proved its safety in terms of cardiac events. Dual anti-HER2 therapy with pertuzumab is currently standard adjuvant therapy in N+ and high-risk N0 early breast cancer (BC) patients. Our study aims to find if it increases early cardiac toxicity compared with trastuzumab alone in BC patients receiving adjuvant radiotherapy.

MATERIALS/METHODS

Operable BC patients who received adjuvant radiotherapy (RT) and trastuzumab with or without pertuzumab between January 2017 and September 2020 in 7 Chinese centers were retrospectively reviewed. The cardiac examination included ultrasonography, electrocardiogram (ECG), NT-proBNP, and cTnI before RT and during follow-up. The cardiac event was any new-onset symptomatic heart disease or abnormality in the cardiac examination after RT.

RESULTS

In total, 711 patients with a median age of 52 years were included, of whom 567 (79.7%) patients were treated with trastuzumab-only and 144 (20.3%) patients received dual anti-HER2 therapy. Adjuvant RT was given concurrently in 140/144 (97.2%) of dual anti-HER2 therapy and 562/567 (99.1%) of trastuzumab alone, respectively. With a median follow-up of 11 months, no patients developed symptomatic heart diseases. Among patients with normal baseline, 17 (2.4%), 86 (12.1%), 18 (2.5%) and 14 (7.3%) developed new-onset diastolic dysfunction, left ventricular ejection fraction (LVEF) decline, abnormal ECG, and abnormal NT-proBNP, respectively. No significant difference was found between the trastuzumab-only and dual anti-HER2 cohort in the incidence of all kinds of new-onset cardiac events (all p > 0.1). Multivariate analysis showed that left-sided (vs right-sided) RT significantly increased the risk of ECG abnormality (HR = 2.32, 95% CI 1.62-3.32, p<0.001). Increased age was an independent risk factor for diastolic dysfunction (HR = 1.1, 95% CI 1.02-1.18, p = 0.0098). Dosimetric analysis showed that patients who developed any cardiac events had increased mean heart dose (397.67±251.08 vs 344.87±236.75 cGy, p = 0.032). A significant increase in risk of cardiac events was found in patients with mean heart dose > 450 cGy (HR = 1.55, 95% CI 1.17-2.05, p = 0.0024), V5 > 26% (HR = 1.51, 95% CI 1.09-2.09, p = 0.013), and V30 > 5.5% (HR = 1.49, 95% CI 1.09-2.04, p = 0.0117), respectively. Further analysis was done in the subgroup of patients treated with left-sided RT, internal mammary nodes RT, or anthracyclines, no difference in risk of cardiac events was found between trastuzumab alone and dual anti-HER2 therapy in concurrent with RT (all p > 0.05).

CONCLUSION

Compared with trastuzumab-only, dual anti-HER2 therapy does not increase early cardiac toxicity in combination with adjuvant RT in BC patients. Cardiac radiation exposure remains the primary risk factor associated with early cardiac toxicity.

Characteristics of solid waste from common generation source in nonferrous smelting industry reveal a new classification method

Solid waste produced by the nonferrous smelting industry has a significant number of notable differences. The lack of recognition of solid waste characteristics is the main factor restricting its disposal and utilization. In this study, we analyzed the main production processes of the nonferrous smelting industry; identified the key production nodes of solid waste; and clarified the characteristics, including the physical, chemical, and pollution characteristics of solid wastes, through a large sample statistical analysis. We found similarities among solid wastes from a common generation source as well as notable differences among the different generation sources: slags and sludges from waste acid treatment and wastewater treatment units had a water content of 27.43-52.71% and 51.14-68.27%, respectively, which were significantly higher than those of other metallurgy and dust collection units; the pH of slags from an electrorefining unit was strongly alkaline; the mineral phase of sludges from wastewater treatment was only calcite; slags from a waste acid treatment unit were mainly in phase of gypsum, claudetite, and anglesite; the chemical composition of slags from pyrometallurgy and hydrometallurgy units was mainly SiO2 and Fe2O3. In this paper, we discuss a new classification method based on a common generation source for the first time. These results are beneficial to guide the disposal, utilization, and management of solid waste.

Convolution Neural Network-Based Automatic Scoring of Coronary Artery Calcification and Its Value to Identify the Risk of Radiation-Induced Cardiac Toxicity on Radiotherapy Planning CT Scans in Breast Cancer Patients

PURPOSE/OBJECTIVE(S)

To develop an automatic scoring of coronary artery calcification (CAC) on breast cancer radiotherapy (RT) planning computed tomography (CT) scans, and to explore its predictive value of CAC for radiation-induced cardiac toxicity.

MATERIALS/METHODS

Planning CT scans of 668 breast cancer patients from two prospective clinical trials (NCT02942615, NCT03829553) were retrospectively reviewed. In total, 34 CTs containing CAC were identified. The training and test samples were 29 and 5, respectively. We proposed a two-stage model for CAC segmentation task with nnU-Net as backbone. The segmentation results were processed by threshold extraction and region growth algorithm. We also employed transfer learning to automatically identify calcification of left anterior descending artery (LAD), right coronary artery (RCA), left circumflex artery (LCX), and left main coronary artery (LM) based on a public dataset of 430 cases from Stanford University. The data of cardiac examination of these 34 patients before and during the follow-up after RT were collected. The cardiac event was any symptomatic heart disease or new-onset abnormality in the cardiac examination after RT.

RESULTS

The mean dice coefficients (DSC) and 95% Harsdorf distance (95HD) of test samples were 0.992 and 0.599 mm, respectively. The mean absolute error (MAE) of CAC Angaston score between ground truth (GT) and predictions was 0.532. The detailed consistency parameters of 5 test samples were shown in Table 1. After 1:2 propensity score matching (PSM), 21 patients had CAC and 42 patients had no CAC were selected. The number of patients with CAC scores of 1 to 10, 11 to 100, and greater than 100 was 10, 9 and 2, respectively. During median follow-up of 9.2 months (range, 1-42.7), 90.5% and 38.1% of patients in CAC cohort and no CAC cohort developed cardiac event (p<0.001). Patients with CAC had significantly increased cardiac events (HR = 2.4; 95% CI, 1.22-4.75; p = 0.0117). The risk of cardiac events increased with CAC scores ([HR]1-10 = 2.1, 95% CI 0.9-4.9; [HR]11-100 = 2.5, 95% CI 1.0-5.9; [HR]>100 = 4.0, 95% CI 0.9-17.4).

CONCLUSION

Our primary results showed that this two-stage segmentation model is capable of achieving automatic CAC scoring which might assist to predict the risk of post-RT cardiac events in breast cancer patients.

Proton Based Stereotactic Radiotherapy for Skull Base Patients: Dosimetric Comparison to 4 Modern Radiation Treatment Modalities

PURPOSE/OBJECTIVE(S)

Re-irradiation with ablative doses to a smaller target volume and strict critical structure constraint is a challenge for modern radiation planning and delivery systems. Several advanced radiation treatment techniques can be used for fractionated stereotactic ablative radiosurgery (FSRS) in select patients with unresectable recurrent head and neck tumors. In this study, in order to better understand the dosimetry advantage of each technique, we compare the stereotactic treatment plans of our new small spot size Hitachi proton treatment unit to those of CyberKnife stereotactic radiosurgery (CK), Gamma Knife radiosurgery (GK), volumetric modulated arc therapy (VMAT), and MR Linac radiotherapy (MRL).

MATERIALS/METHODS

Ten FSRS skull base patients treated at our institution using VMAT (n = 5) or GK (n = 5) techniques. Intensity-modulated proton therapy (IMPT) plans were created in Raystation using Monte Carlo dose calculation algorithm. VMAT, CK, GK and MRL plans were generated in RayStation, Accuray Precision, Leksell Gamma Plan, and Monaco treatment planning systems, separately. Planning goals were to achieve the best target coverage of prescribed dose without compromising the critical organs at risk dose volume constraints of the clinical treatment plans. Plans were compared based on percent CTV coverage, Paddick conformity index (PCI), gradient index (GI, V50/V100), dose homogeneity index (HI, (D2-D98)/D50), low dose bath volume (LDBV, ratio of total volume irradiated between 20% and 50% prescription dose and the target volume), beam-on-time (BOT), and mean/maximum doses to brainstems.

RESULTS

The median target volume was 15.5 cm3 (range 1.0 - 36.23 cm3). The prescription was 45 Gy in 5 fractions for VMAT patients, and 21 - 27 Gy in 3 fractions for GK patients. The comparison of the treatment plans of these 5 delivery modalities was shown in table. All techniques achieved comparable CTV coverage. GI was superior for GK plans and outstanding in CK and IMPT plans. IMPT plans were also outstanding in regard to BOT and PCI. Significantly improved HI, LDBV and brainstem mean doses were achieved in IMPT plans. For adjacent brainstem and other OARs, maximum doses were comparable among all techniques.

CONCLUSION

In these five advanced radiation therapy modalities, proton therapy SBRT showed dosimetric advantage over other modalities to spare nearby OARs without sacrifice of target coverage. Further studies are needed to utilize this clinical benefit and investigate plan robustness.

Correlation between Lymph Node Regression Grading and Tumor Regression Grading after Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer

PURPOSE/OBJECTIVE(S)

This study aimed to determine the relationship between tumor regression grading (TRG) and lymph node regression grading (LRG) after neoadjuvant chemoradiotherapy (nCRT) for locally advanced rectal cancer (LARC).

MATERIALS/METHODS

The study was a retrospective analysis of the clinical data of LARC patients who underwent preoperative nCRT at one institution. A total of 101 rectal cancer patients who received nCRT and underwent total rectal mesenteric excision (TME) were included. Pathologists independently assessed the pathological response of the primary tumor and lymph nodes (LN) to nCRT using TRG and LRG, respectively. The highest LRG score for each patient was defined as LRGmax, and LRGsum was the overall tumor burden of all LNs in the specimen.

RESULTS

The study included 101 LARC patients who underwent nCRT and TME. The patient population consisted of 65 males and 36 females with an average age of 54.86 years (range 20-81 years), of which 68 were aged 60 years or younger and 33 were older than 60. The radiotherapy treatment plan consisted of 1.8-2Gy per dose, administered 5 times per week for a total dose of 45-50.4Gy, along with oral capecitabine chemotherapy (825 mg/m2, bid) on the day of radiation therapy. The chemotherapy treatment plan included XELOX, mFOLFOX6, and FOLFOX4. The cTNM stage of the tumor before surgery was cT2 in 2 cases, cT3 in 63 cases, and cT4 in 36 cases. Eight cases were cN0 and 93 were cN+. After surgery, the ypTNM stage was T0 in 19 cases, T1 in 4 cases, T2 in 27 cases, T3 in 45 cases, and T4 in 6 cases. The N stage was N0 in 76 cases, N1 in 20 cases, and N2 in 5 cases. TRG was 0 in 17 cases (16.8%), 1 in 15 cases (14.9%), 2 in 61 cases (60.4%), and 3 in 8 cases (7.9%). LRGmax scores were 0 in 66 cases (65.3%), 1 in 17 cases (16.8%), 2 in 5 cases (5.0%), 3 in 3 cases (3.0%), 4 in 5 cases (5.0%), and 5 in 5 cases (5.0%). LRGsum scores were ≤3 in 85 cases (84.2%), 4-9 in 11 cases (10.9%), and ≥10 in 5 cases (5.0%). Correlation analysis showed that LRGmax was significantly correlated with TRG, ypT, and ypN (P = 0.038, P = 0.015, P < 0.01), with correlation coefficients of 0.184, 0.212, and 0.626, respectively. There was no significant correlation between LRGmax and cT and cN+. Similarly, LRGsum was significantly correlated with TRG, ypT, and ypN (P = 0.022, P = 0.002, P < 0.01) with correlation coefficients of 0.212, 0.276, and 0.707, respectively. There was no significant correlation between LRGsum and cT and cN. The results of our study indicate a significant correlation between LRG and TRG (P = 0.022). Additionally, LRG was found to be positively correlated with the ypT and ypN stages of the primary tumor and lymph nodes post-surgery, with correlation coefficients of 0.276 and 0.707, respectively (P = 0.002 and P<0.01). No significant correlations were observed between LRG and cT and cN+ stages.

CONCLUSION

Our findings demonstrate a significant association between LRG and TRG, as well as a positive correlation between LRG and the ypT and ypN stages of the primary tumor and lymph nodes following surgery.

Cost-Effectiveness of Short-Course Radiotherapy Based Total Neoadjuvant Therapy for Locally Advanced Rectal Cancer in China

PURPOSE/OBJECTIVE(S)

The phase III STELLAR (NCT02533271) trial demonstrated that four cycles of chemotherapy after short-course radiotherapy (SCRT-TNT) were not inferior to the standard care of long-course concurrent radiotherapy (LCRT) in patients with locally advanced rectal cancer (LARC). This study assessed the cost-effectiveness of SCRT-TNT versus LCRT in locally advanced rectal cancer in China on the basis of the STELLAR trial.

MATERIALS/METHODS

A Markov model was used to synthesize the healthcare costs and benefits of LARC patients based on results from the STELLAR trial. The model assumes that LARC who meet the inclusion criteria of the STELLAR trial experience four possible states: No Evidence of Disease (NED), locally recurrence, distant metastases, or any death from rectal cancer or other unrelated causes, where local recurrence continues to be classified as resectable and unresectable. The transition status period is 3 month, and 5 years is used to calculate direct medical costs and health benefits. The probabilities of states transition after SCRT-TNT or LCRT were derived from the results of the STELLAR trial and previous published article (Table.1). Costs were evaluated from the Chinese payer's perspective reported in early 2022 US dollars (US$1 = 6.78 Chinese Yuan). Sensitivity analyses were performed for key variables. Cost-effectiveness was evaluated using the incremental cost-effectiveness ratio and net monetary benefits. Effectiveness was defined as quality-adjusted life-years (QALYs). Willingness-to-pay (WTP) threshold was set at $43500/QALY. Data were collected from October 3, 2020, to September 20, 2021, and analyzed from November 15, 2020, to October 25, 2021.

RESULTS

During the 5-year horizon, for the base case scenario, SCRT-TNT incurred a lower total cost and higher QALYs compared with LCCRT. The total cost was $65767 and QALYs were 1.77 for SCRT-TNT; for LCCRT, the total cost was $72802 and QALYs were 1.64. This resulted in an ICER of -$ 55470.69 per QALY. Therefore, SCRT-TNT was a cost-saving and dominating treatment strategy compared with LCRT. Sensitivity analysis showed that ICERs were most sensitive to the parameters of distant metastases risk after treatment.

CONCLUSION

SCRT-TNT in locally advanced rectal cancer can be a cost-effective alternative to LCRT in China, and should be considered in appropriately selected patients.

Real-Time Spinal Cord Motion Tracking for MR-guided Spine SBRT (A Pilot Study)

PURPOSE/OBJECTIVE(S)

The aim of this study was to assess the feasibility of real-time motion tracking of the spinal cord using 2D-cine MRI on the MR-Linac system. Spinal SBRT delivers high-precision doses to targets near the spinal cord but with the dosimetric cord tolerance sometimes defined using a spinal cord PRV and the treatment alignment visualizing a surrogate measure (spinal canal) with cone beam CT guidance. MR-guided spine SBRT enables clear visualization of the true spinal cord and real-time monitoring of the cord during treatment, which may allow for increased cord dose constraints and offer new treatment options for patients with epidural disease.

MATERIALS/METHODS

A Motion Monitoring Research Package (MMRP) that has the similar tracking functionality as the future motion management system for a 1.5 T MR-Linac system was used to track real-time target motion on 2D orthogonal T2-weighted bFFE cine MRI using a reference 3D T2 MRI scan to locate tracking object initially. The spinal cord was contoured from the T2 MRI scan as the tracking object, and the cine images were obtained in sagittal and coronal planes at the center of the contoured spinal cord with a temporal resolution of 1.2 seconds. The motion tracking data was collected for 20 min and retrospectively analyzed using standard deviation of motion was collected from two volunteers immobilized with the Klarity SBRT system on the MR-Linac couch during MRI scans of their cervical, thoracic, and lumbar spines.

RESULTS

In the thoracic spinal cord, the was 0.07mm (left-right excursion range: ±0.15mm), 0.15mm (anterior-posterior: ±0.26mm), and 0.27mm (superior-inferior: ±0.53mm). In the lumbar spinal cord, the standard deviation was 0.06mm (±0.12mm), 0.1mm (±0.14mm), and 0.1mm (±0.27mm). In the cervical spine, since the tracking accuracy in Sup/Inf direction was compromised by tilted spine orientation in the orthogonal 2D image, a single entire vertebra including the spinal cord was tracked with a standard deviation of 0.19mm (±0.31mm), 0.27mm (±0.62mm), and 0.25mm (±0.4mm).

CONCLUSION

This study demonstrated the possibility of real-time tracking of the spinal cord using 2D-cine MRI on an MR-Linac system. Future work will aim to increase sample size and evaluate the reproducibility of the tracking results over time. The excursion of the thoracic/lumbar spinal cord was found to be less than 0.5mm, while the anterior/posterior or superior-inferior excursion of the cervical spine was greater than 1.0mm during the 20-minute scan.

[Application of augmented reality navigation combined with indocyanine green fluorescence imaging technology in the accurate guidance of laparoscopic anatomical segment 8 liver resection]

Objective: To investigate the application value of augmented reality navigation combined with indocyanine green(ICG) fluorescence imaging technology in laparoscopic anatomical segment 8 liver resection. Methods: Clinical and pathological data from 8 patients with hepatocellular carcinoma located in segment 8 of the liver admitted to the First Department of Hepatobiliary Surgery,Zhujiang Hospital,Southern Medical University from October 2021 to October 2022 were collected restrospectively. Among them,there were 5 males and 3 females,aged between 40 and 72 years. During the operation,the self-developed laparoscopic augmented reality surgical navigation system was used to integrate the three-dimensional liver model with the laparoscopic scene,and ICG fluorescence imaging technology was used to guide the anatomical liver resection of segment 8. The predicted liver resection volume and actual liver resection volume,related surgical indicators and postoperative complications were analyzed. Results: Among the 8 patients, 4 underwent laparoscopic anatomical segment 8 liver resection,1 underwent laparoscopic anatomical ventral subsegment of segment 8 liver resection,2 underwent laparoscopic anatomical ventral subsegment combined with medial subsegment of segment 8 liver resection, and 1 underwent laparoscopic anatomical dorsal subsegment of segment 8 liver resection. All operations were completed under the guidance of augmented reality navigation combined with ICG fluorescence imaging,without conversion to open surgery. The operation time was (276.3±54.8)minutes(range:200 to 360 minutes). Intraoperative blood loss was (75.0±35.4)ml(range:50 to 150 ml). No blood transfusion was performed during the operation. The length of postoperative hospital stay was (7.6±0.8)days(range:7 to 9 days). There were no deaths or postoperative complications such as bleeding or biliary fistula during the perioperative period. Conclusion: Augmented reality navigation combined with ICG fluorescence imaging technology can guide the implementation of laparoscopic anatomical segment 8 liver resection.

Clinical application of laparoscopic continuous interposition jejunostomy with double-tract anastomosis and esophagogastric anastomosis: a retrospective study

OBJECTIVE

The aim of this study was to compare the early clinical outcomes of laparoscopic-assisted proximal gastrectomy with continuous interposition of jejunal cis-peristaltic dual-channel anastomosis and esophagogastric anastomosis.

PATIENTS AND METHODS

A retrospective analysis of 130 patients who underwent laparoscopic-assisted radical resection of proximal gastric cancer in the Department of Gastrointestinal Surgery at the Affiliated Hospital of Chengde Medical College between June 2018 and October 2022 was conducted. Continuous interposition jejunal double-channel anastomosis (double-tract anastomosis) was used in 71 patients and esophagogastric anastomosis (esophagogastrostomy) in 59 patients. The basic clinical data, preoperative and postoperative clinical test indexes, postoperative complications and improvement of symptoms compared to preoperative ones, basic nutritional status and Visick classification of esophageal reflux symptoms at 6 months after surgery were compared between the two groups. Postoperative contrast images of patients in the continuous interposition jejunal double-tract group were collected and analyzed for the ratio of contrast agent remaining in the stomach to that remaining in the small intestinal channel.

RESULTS

A total of 130 cases meeting the criteria were included in this study, including 71 cases involving the double-tract (DT) anastomosis method and 59 cases involving the esophagogastrostomy (EG) anastomosis method. There was no significant difference in preoperative information and perioperative safety between the two groups. Visick score of the DT group was significantly better than that of the EG group.

CONCLUSIONS

Double-tract jejunal anastomosis can effectively improve esophageal reflux symptoms after proximal gastrectomy. At the same time, its anastomotic method also improves the nutritional status in the short term compared to the esophagogastric anastomosis and is a more ideal procedure for reconstructing the digestive tract after proximal gastrectomy.

A Prospective Clinical Trial of Radiotherapy Combined with PD-1 Inhibitors and GM-CSF, Sequentially Followed by IL-2 (PRaG 2.0) Regimen in Advanced Refractory Solid Tumors

PURPOSE/OBJECTIVE(S)

Radiotherapy could stimulate the immune response and might synergize with PD-1/PD-L1 inhibitors in the clinical treatment of malignancies. Our previous PRaG trial also demonstrated that SBRT/HFRT in combination with PD-1 inhibitors and granulocyte macrophage-colony stimulating factor (GM-CSF) could improve clinical response in patients with advanced refractory solid tumors (ChiCTR1900026175). To further improve the efficacy of immunotherapy combined with radiotherapy, we conducted the PRaG 2.0 trial (ClinicalTrials.gov: NCT04892498) and optimized the PRaG regimen by adding interleukin-2 (IL-2). Preliminary results of PRaG 2.0 had been reported in the 64th ASTRO. Now we report an updated result.

MATERIALS/METHODS

The PRaG 2.0 regimen was administered to patients with advanced refractory solid tumors who lacked or were unable to tolerate standard-of-care treatments. A treatment cycle consisted of SBRT or HFRT (5 or 8 Gy×2-3f) delivered for one metastatic lesion, PD-1 inhibitor dosing within one week after completion of radiotherapy, GM-CSF 200μg subcutaneous (SC) injection once daily for 7 days, and then sequentially followed by IL-2 2million IU SC once daily for 7 days. PRaG 2.0 regimen was repeated every 21 days for at least 2 cycles until no appropriate lesions for irradiation or reached the tolerance dose of normal tissues. Patients who could not continue radiotherapy and had not yet developed progression disease (PD) allowed PD-1 inhibitors to be continued as maintenance therapy until PD or unacceptable toxicity but no more than one year. The primary endpoint was Progression-Free Survival (PFS).

RESULTS

As of 31st October 2022, 51 patients were enrolled in the study, and 42 completed at least one tumor assessment. The median Progression-Free Survival (PFS) was 5.8 months, and the median overall survival (OS) was 13.5 months. The objective response rate (ORR) was 21.4%, and the disease control rate (DCR) was 61.9% according to RECIST version 1.1. Lower plasma levels of Interleukin (IL)-6 and IL-17 at baseline were found to be associated with improved PFS. Treatment-related adverse events (TRAE) occurred in 34 of 42 (78.6%) patients, Grade ≥ 3 TRAEs occurred in 4 patients (9.5%). TRAEs leading to discontinuation of all study treatments occurred in three patients (7.1%).

CONCLUSION

The PRaG 2.0 trial demonstrates that PD-1 inhibitors in combination with SBRT/HFRT, GM-CSF, and IL-2 could be a potential treatment regimen for patients with advanced refractory solid tumors, with an acceptable benefit/risk profile.

Homeostatic Balance of Gut Microbiota in Head and Neck Squamous Cell Carcinoma Patients during Radiotherapy

PURPOSE/OBJECTIVE(S)

Radiotherapy is the major treatment for head and neck squamous cell carcinoma (HNSCC). Oral microbiota changes have been described before. However, gut microbiota changes in HNSCC patients who received local radiotherapy remain unclear. We aim to investigate the dynamic change of gut microbiota composition in HNSCC patients undergoing radiotherapy and to construct the radiotherapy related gut microbiota database in HNSCC patients.

MATERIALS/METHODS

We enrolled 47 HNSCC patients who scheduled with radiotherapy solely. Intensity-modulated radiotherapy (IMRT) was the standard radiotherapy technique for all the enrolled patients. The field was irradiated with a total dose of 60-66Gy in 30-33 fractions. Fecal pellets were collected at three time points. Bacterial genomic DNA was isolated using magnetic beads and then analyzed by the Illumina MiSeq Sequencing System based on the V3-V4 hypervariable regions of the 16S rRNA gene.

RESULTS

A total of 194 genera which belonged to 27 phyla were found in 141 samples. Increased abundance of microbiota in diversity and richness was observed in mid-radiotherapy group. Moreover, Bacteroides, Blautia, and Phascolarctobacterium were three main genera in all three groups and the mid-radiotherapy group had the highest relative abundance of Phascolarctobacterium. What's more, most significantly altered bacteria shared the same variation pattern which was increased in mid-radiotherapy while decreased to the almost same level of as pre-radiotherapy in post-radiotherapy group.

CONCLUSION

Local radiotherapy can affect the composition of the gut microbiota in HNSCC patients during the mid-term of radiotherapy. However, self-stabilized ability maintained the gut microbiota homeostasis in the end.

Multi-constraint point set registration with redundant point removal for the registration of coronary arteries

BACKGROUND

Coronary artery disease (CAD) is the leading cause of death worldwide. The registration of the coronary artery at different phases can help radiologists explore the motion patterns of the coronary artery and assist in the diagnosis of CAD. However, there is no automatic and easy-to-execute method to solve the missing data problem that occurs at the endpoints of the coronary artery tree. This paper proposed a non-rigid multi-constraint point set registration with redundant point removal (MPSR-RPR) algorithm to tackle this challenge.

METHODS

Firstly, the MPSR-RPR algorithm roughly registered two coronary artery point sets with the pre-set smoothness regularization parameter and Gaussian filter width value. The moving coherent, local feature, and the corresponding relationship between bifurcation point pairs were exploited as the constraints. Next, the spatial geometry information of the coronary artery was utilized to automatically recognize the vessel endpoints and to delete the redundant points of the coronary artery. Finally, the algorithm continued carrying out the multi-constraint registration with another group of the pre-set parameters to improve the alignment performance.

RESULTS

The experimental results demonstrated that the MPSR-RPR algorithm achieved a significantly lower mean value of the modified Hausdorff distance (MHD) compared to the other state-of-the-art methods for addressing the serious missing data in the left and right coronary arteries.

CONCLUSION

This study demonstrated the effectiveness of the proposed algorithm in aligning coronary arteries, providing significant value in assisting in the diagnosis of coronary artery and myocardial lesions.

The Safety and Efficacy of SCART for Bulky Metastatic or Recurrent Cancer, a Phase I Study

PURPOSE/OBJECTIVE(S)

We are proposing a new treatment methodology, (called Stereotactic Centralized Ablative Radiation Therapy, (SCART), for bulky or metastatic tumors, which is based on the principles of SFRT, by using SBRT methods to deliver an ablative radiation dose to the central portion of the target while keeping the dose to surrounding normal tissue to a relatively low level. We performed a prospective dose escalation study of SCART for bulky metastatic or recurrent cancer. The purpose of the study was to determine dose-limiting toxicities (DLTs) and the Maximum Tolerated Dose (MTD) of SCART.

MATERIALS/METHODS

This study was registered at ClinicalTrials.gov Identifier: NCT0488198, and approved at Foshan Chancheng Hospital. Patients with unresectable solid "bulky" nonhematological malignancies with limited treatment options were enrolled and received SCART with a prescription to the central spot in the tumor with a peripheral dose to the tumor edge at around 20% isodose line of the prescription dose. Five dose levels were proposed. The primary endpoint was the maximum tolerated dose (MTD), defined as the highest dose where zero of three or one of six patients experienced grade 3 dose-limiting toxicity (DLT), scored according to the Common Toxicity Criteria for Adverse Events v. 4.03, up to 6 months after SCART.

RESULTS

A total of 21 patients received SCART and have eligible data for study follow-up. The dose was escalated for two patients to 24 GyX3. No grade 3 toxicity was observed in any of the enrolled patients. The median SCART dose was 18 Gy (range: 15 - 24). Six out of the 18 patients with data for overall survival (OS) died, and the median time to death was 16.29 months (range: 0.99 - 25.58). Three patients out of the 15 patients with available data for local recurrence (LR) were found to have an LR and the median time to LR was 16.01 months (range: 0.99 - 25.58). There appears to be a trend of tumors decreasing from the patient's first visit date, or pre-SCART, to their final volume post-SCART. The mean percent change for tumor shrinkage between first visit volumes and post-SCART volumes was 49.49% (SD: 40.89, p-value:0.009). Of 15 patients with available data for progression free survival, 9 had a local recurrence or were deceased. Estimated median survival (i.e., when survival is 50%) was equal to16.80 months (95% CI = 13.90, NA). The survival rate at 12 months and 24 months were72.22% and 24.07%, respectively. Of 15 patients with available data for time to local recurrence, 3 people had a local recurrence. The percent of patients that were free from local recurrence at one and two years after the beginning of SCART treatment was 85.56% for both.

CONCLUSION

Despite the high dose delivered and the excellent local control achieved; the incidence of Any toxicity was unexpectedly low. Multiple courses of SCART are possible. The optimal dose, volume and timing of SCART still need more study.

[Spatial distribution of Oncomelania hupensis spread in Hubei Province from 2020 to 2022]

OBJECTIVE

To identify the spatial distribution pattern of Oncomelania hupensis spread in Hubei Province, so as to provide insights into precision O. hupensis snail control in the province.

METHODS

Data pertaining to emerging and reemerging snails were collected from Hubei Province from 2020 to 2022 to build a spatial database of O. hupensis snail spread. The spatial clustering of O. hupensis snail spread was identified using global and local spatial autocorrelation analyses, and the hot spots of snail spread were identified using kernel density estimation. In addition, the correlation between environments with snail spread and the distance from the Yangtze River was evaluated using nearest-neighbor analysis and Spearman correlation analysis.

RESULTS

O. hupensis snail spread mainly occurred along the Yangtze River and Jianghan Plain in Hubei Province from 2020 to 2022, with a total spread area of 4 320.63 hm2, including 1 230.77 hm2 emerging snail habitats and 3 089.87 hm2 reemerging snail habitats. Global spatial autocorrelation analysis showed spatial autocorrelation in the O. hupensis snail spread in Hubei Province in 2020 and 2021, appearing a spatial clustering pattern (Moran's I = 0.003 593 and 0.060 973, both P values < 0.05), and the mean density of spread snails showed spatial aggregation in Hubei Province in 2020 (Moran's I = 0.512 856, P < 0.05). Local spatial autocorrelation analysis showed that the high-high clustering areas of spread snails were mainly distributed in 50 settings of 10 counties (districts) in Hubei Province from 2020 to 2022, and the high-high clustering areas of the mean density of spread snails were predominantly found in 219 snail habitats in four counties of Jiangling, Honghu, Yangxin and Gong'an. Kernel density estimation showed that there were high-, secondary high- and medium-density hot spots in snail spread areas in Hubei Province from 2020 to 2022, which were distributed in Jingzhou District, Wuxue District, Honghu County and Huangzhou District, respectively. There were high- and medium-density hot spots in the mean density of spread snails, which were located in Jiangling County, Honghu County and Yangxin County, respectively. In addition, the snail spread areas negatively correlated with the distance from the Yangtze River (r = -0.108 9, P < 0.05).

CONCLUSIONS

There was spatial clustering of O. hupensis snail spread in Hubei Province from 2020 to 2022. The monitoring and control of O. hupensis snails require to be reinforced in the clustering areas, notably in inner embankments to prevent reemerging schistosomiasis.

[The mediating role of resilience between social capital at work and anxiety of medical staff]

Objective: To explore the influence of social capital at work on anxiety of medical staff, and the mediating role of resilience. Methods: From March to May 2022, a total of 201 medical staff in the Affiliated Hospital of Jining Medical University were investigated with the General Information Questionnaire, Workplace Social Capital Scale, Connor-Davidson Resilience Scale (CD-RISC-10) and Generalized Anxiety Disorder-7 (GAD-7) . K-S method was used for normdity test of econometic voriobles, and normal distribution data were represented by Mean±SD, Pearson correlation analysis and linear regression analysis were used to test correlation between variables and mediating effect, and Bootstrap method was carried out by SPSS macro program PROCESS v3.5 to verify the mediating effect. Results: The detection rate of anxiety was 59.20% (119/201) in medical staff. The scores of social capital at work (28.90±5.83) and resilience (31.55±4.98) were negatively correlated with the score of anxiety (7.20±2.06) (r=-0.338, -0.510, P<0.001) , while the score of social capital at work was positively correlated with resilience (r=0.392, P<0.001) . Workplace social capital positively predicted resilience (β=0.392, P<0.001) , and both workplace social capital (β=-0.222, P=0.001) and resilience at work (β=-0.423, P<0.001) negatively predicted anxiety score. The direct effect of social capital in the workplace of medical staff on anxiety was -0.222 (95%CI: -0.349~-0.095, P=0.001) , and the indirect effect of resilience on anxiety was -0.166 (95%CI: -0.265~-0.080) . The resilience of medical staff had a partial mediating effect between workplace social capital and anxiety, which accounted for 42.78% of the total effect. Conclusion: The resilience of medical staff has a partial mediating effect between workplace social capital and anxiety. Workplace social capital can not only directly affect the anxiety of medical staff, but also indirectly affect it through resilience.

A real-time contouring feedback tool for consensus-based contour training

Purpose

Variability in contouring structures of interest for radiotherapy continues to be challenging. Although training can reduce such variability, having radiation oncologists provide feedback can be impractical. We developed a contour training tool to provide real-time feedback to trainees, thereby reducing variability in contouring.

Methods

We developed a novel metric termed localized signed square distance (LSSD) to provide feedback to the trainee on how their contour compares with a reference contour, which is generated real-time by combining trainee contour and multiple expert radiation oncologist contours. Nine trainees performed contour training by using six randomly assigned training cases that included one test case of the heart and left ventricle (LV). The test case was repeated 30 days later to assess retention. The distribution of LSSD maps of the initial contour for the training cases was combined and compared with the distribution of LSSD maps of the final contours for all training cases. The difference in standard deviations from the initial to final LSSD maps, ΔLSSD, was computed both on a per-case basis and for the entire group.

Results

For every training case, statistically significant ΔLSSD were observed for both the heart and LV. When all initial and final LSSD maps were aggregated for the training cases, before training, the mean LSSD ([range], standard deviation) was -0.8 mm ([-37.9, 34.9], 4.2) and 0.3 mm ([-25.1, 32.7], 4.8) for heart and LV, respectively. These were reduced to -0.1 mm ([-16.2, 7.3], 0.8) and 0.1 mm ([-6.6, 8.3], 0.7) for the final LSSD maps during the contour training sessions. For the retention case, the initial and final LSSD maps of the retention case were aggregated and were -1.5 mm ([-22.9, 19.9], 3.4) and -0.2 mm ([-4.5, 1.5], 0.7) for the heart and 1.8 mm ([-16.7, 34.5], 5.1) and 0.2 mm ([-3.9, 1.6],0.7) for the LV.

Conclusions

A tool that uses real-time contouring feedback was developed and successfully used for contour training of nine trainees. In all cases, the utility was able to guide the trainee and ultimately reduce the variability of the trainee's contouring.

Search for a Dark-Matter-Induced Cosmic Axion Background with ADMX

We report the first result of a direct search for a cosmic axion background (CaB)-a relativistic background of axions that is not dark matter-performed with the axion haloscope, the Axion Dark Matter eXperiment (ADMX). Conventional haloscope analyses search for a signal with a narrow bandwidth, as predicted for dark matter, whereas the CaB will be broad. We introduce a novel analysis strategy, which searches for a CaB induced daily modulation in the power measured by the haloscope. Using this, we repurpose data collected to search for dark matter to set a limit on the axion photon coupling of a CaB originating from dark matter cascade decay via a mediator in the 800-995 MHz frequency range. We find that the present sensitivity is limited by fluctuations in the cavity readout as the instrument scans across dark matter masses. Nevertheless, we suggest that these challenges can be surmounted using superconducting qubits as single photon counters, and allow ADMX to operate as a telescope searching for axions emerging from the decay of dark matter. The daily modulation analysis technique we introduce can be deployed for various broadband rf signals, such as other forms of a CaB or even high-frequency gravitational waves.

Relationship between dietary patterns and diabetic microvascular complications in patients with type 2 diabetes mellitus

OBJECTIVE

This study aimed to investigate the relationship between different dietary patterns and diabetic microvascular complications in patients with type 2 diabetes mellitus.

PATIENTS AND METHODS

This study was conducted based on the Chinese Chronic Disease and its Risk Factor Surveillance System. A multi-stage stratified sampling method was used to randomly select two districts (Henghualing District, Taiyuan City, and Yuzi District, Jinzhong City) and two counties (Huguan County, Changzhi City, and Jiang County, Yuncheng City) from the chronic disease surveillance sites in Shanxi Province to collect general information, dietary records, physical measurements, and laboratory tests. In total, 1,227 patients were enrolled according to the study criteria. Factor analysis was performed to construct six dietary patterns, and the relationship between dietary pattern scores and type 2 diabetic microvascular complications was analysed using binary logistic regression after correcting for confounders.

RESULTS

(1) Regarding the prevalence of type 2 diabetic microvascular complications and dietary characteristics, the prevalence of microvascular complications in patients with type 2 diabetes mellitus was 55.3% and was higher in urban than in rural areas. The prevalence of diabetic kidney disease (DKD), diabetic retinopathy, and diabetic peripheral neuropathy (DPN) were 21.4%, 12.7%, and 38.0%, respectively. (2) Six dietary patterns were constructed, namely, 'animal protein', 'coarse grains and plant protein', 'nuts and fruits', 'refined grains and vegetables', 'dairy', and 'added sugars', with factor contributions of 15.42%, 9.99%, 8.23%, 8.16%, 7.56%, and 7.28% respectively, explaining 56.64% of the total dietary variation. (3) After adjusting for confounding variables, the results of binary logistic regression indicated that patients in the highest quartile of dietary pattern scores for 'nuts and fruits' experienced a 43.3% lower risk of DKD compared to those in the lowest quartile [odds ratio (OR) = 0.567; 95% confidence interval (CI), 0.359-0.894; p < 0.001]. Similarly, patients in the highest quartile of dietary pattern scores for 'animal protein' had a 42.8% lower risk of DPN compared with those in the lowest quartile (OR = 0.572; 95% CI, 0.388-0.843; p < 0.05).

CONCLUSIONS

The results of this study suggest that in patients with type 2 diabetes mellitus, a 'nuts and fruits' dietary pattern reduces the risk of DKD and an 'animal protein' dietary pattern reduces the risk of DPN.

A transformer-based hierarchical registration framework for multimodality deformable image registration

Deformable image registration (DIR) between daily and reference images is fundamentally important for adaptive radiotherapy. In the last decade, deep learning-based image registration methods have been developed with faster computation time and improved robustness compared to traditional methods. However, the registration performance is often degraded in extra-cranial sites with large volume containing multiple anatomic regions, such as Computed Tomography (CT)/Magnetic Resonance (MR) images used in head and neck (HN) radiotherapy. In this study, we developed a hierarchical deformable image registration (DIR) framework, Patch-based Registration Network (Patch-RegNet), to improve the accuracy and speed of CT-MR and MR-MR registration for head-and-neck MR-Linac treatments. Patch-RegNet includes three steps: a whole volume global registration, a patch-based local registration, and a patch-based deformable registration. Following a whole-volume rigid registration, the input images were divided into overlapping patches. Then a patch-based rigid registration was applied to achieve accurate local alignment for subsequent DIR. We developed a ViT-Morph model, a combination of a convolutional neural network (CNN) and the Vision Transformer (ViT), for the patch-based DIR. A modality independent neighborhood descriptor was adopted in our model as the similarity metric to account for both inter-modality and intra-modality registration. The CT-MR and MR-MR DIR models were trained with 242 CT-MR and 213 MR-MR image pairs from 36 patients, respectively, and both tested with 24 image pairs (CT-MR and MR-MR) from 6 other patients. The registration performance was evaluated with 7 manually contoured organs (brainstem, spinal cord, mandible, left/right parotids, left/right submandibular glands) by comparing with the traditional registration methods in Monaco treatment planning system and the popular deep learning-based DIR framework, Voxelmorph. Evaluation results show that our method outperformed VoxelMorph by 6 % for CT-MR registration, and 4 % for MR-MR registration based on DSC measurements. Our hierarchical registration framework has been demonstrated achieving significantly improved DIR accuracy of both CT-MR and MR-MR registration for head-and-neck MR-guided adaptive radiotherapy.

Electronic structures, transport properties, and optical absorption of bilayer blue phosphorene nanoribbons

Based on first-principles density functional theory and nonequilibrium Green's function, we study the electronic band structures, the electronic transport properties, and the optical absorption of bilayer blue phosphorene nanoribbons (BPNRs). Both bilayer armchair BPNRs (a-BPNRs) and zigzag BPNRs (z-BPNRs) behave as semiconductors in the narrow nanoribbon case and metals in the wide nanoribbon case, sharply different from their monolayer counterparts where the monolayer a-BPNRs (z-BPNRs) are always semiconducting (metallic). This indicates that interlayer couplings or the increasing layer number may induce the switching of the conductivity of the monolayer BPNRs, which is absent in graphene and phosphorene nanoribbons. Furthermore, we explore the edge states of the energy bands near Fermi energy, and find that there are almost no pure edge-state band branches in the bilayer BPNRs, which can be attributed to the interlayer couplings between the edge-states in one layer and the bulk-states in the other. Consequently, the resulting complex band structures cannot be directly analyzed any more in the framework of the two-body coupling picture just according to the simple band structures of the monolayer BPNRs. Finally, we present the current-voltage characteristics and the optical absorption of the bilayer a-BPNRs and z-BPNRs. The influences of the nanoribbon width and the interlayer couplings on the current and the anisotropic optical absorption can be understood based on the complex energy band structures. This research should be an important reference of extending the field of BPNRs from the monolayer to the bilayer case, and deepen the understanding of the difference between the monolayer and bilayer nanoribbons in different materials.

[Association between volatile organic compounds and mortality risk of stroke]

Objective: To investigate the effect of volatile organic compounds (VOCs) exposure in the atmosphere on the risk of daily death from stroke in Guangzhou. Methods: Daily average concentrations of twelve atmospheric VOCs, meteorological factors, and daily deaths for stroke and its subtypes (including ischemic and hemorrhagic stroke) in Guangzhou from 2020 to 2021 were collected. The time-series Poisson generalized additive model was established to analyze the relationship between daily average concentrations of atmospheric VOCs and daily mortality from a stroke on different lag days. The season, gender, and age group further performed stratification analysis. Results: Toluene and n-pentane were associated with a higher mortality risk from stroke and its subtypes. For each interquartile range (IQR) increment in toluene concentration at lag0- 1 days, the RRs for mortality from stroke and hemorrhagic stroke were 1.060 (95%CI: 1.036-1.085) and 1.071 (95%CI: 1.030-1.113), respectively. For each IQR increment in n-pentane concentration, the RR for mortality from ischemic stroke was 1.064 (95%CI: 1.030-1.099). The effect estimates of VOCs may be higher during the cold season and among women and people aged ≥75 years. For each IQR increment in toluene concentration, the RRs for mortality risk of stroke in the cold season and women were 1.099 (95%CI: 1.056-1.143) and 1.085 (95%CI: 1.050-1.120), respectively. For n-pentane, the RR for death risk of stroke in people aged ≥75 years old was 1.072 (95%CI: 1.036-1.109). Results of sensitivity analysis showed that the effect estimates fluctuated less when PM2.5 and O3 were separately introduced for the two-pollutant model, as well as changing the degrees of freedom for covariates. Conclusions: This study suggests that VOCs may be an independent risk factor for daily mortality from stroke. Moreover, Toluene presented the most significant health impact.

[Epidemiological characteristics of falls in the elderly in Jiangsu from 2006 to 2021]

Objective: To understand the epidemiological characteristics and influencing factors of elderly unintentional fall-related injuries (EUFI) in Jiangsu from 2006 to 2021 and provide a scientific basis for the prevention of falls in the elderly and the formulation of related policies. Methods: Data on EUFI was collected from the first diagnosed cases in the injury surveillance hospitals in Jiangsu from 2006 to 2021, and epidemiological characteristics of injuries were analyzed. logistic regression was performed to identify the risk factors for EUFI. Results: The number of EUFI increased from 2006 to 2021, ranked as the first cause of elderly unintentional injuries during these years. The proportion of EUFI among elderly unintentional injuries increased in the same period. The male-to-female ratio is 1∶1.4. Falls mainly occurred during 8:00-10:00 am (32.7%). The most common place where falls occurred was at home (63.6%). From 2006 to 2014, leisure activities (62.1%), housework/study (23.1%), and work (5.2%) were the top three activities when injuries occurred. During 2015-2021, leisure activities (41.7%), housework/study (22.6%) and walking (20.5%) were the top three activities when injuries occurred. The major fall-related injuries were fractures (39.9%), with the injured parts at low limbs (32.5%), of which most were mild injuries (60.3%), and the primary outcome was hospitalization after treatment (74.1%). logistic regression showed that the risk factors of EUFI were female, old age, immigrants, winter, public residence, housework/study, and leisure activities. Higher education, occupation of household and production and transportation equipment operators were protective factors (all P<0.05). Conclusions: Fall is the leading cause of unintentional injuries in the elderly in Jiangsu, especially the elderly female population. Corresponding measures should be taken to prevent and intervene in falls in the elderly in the community according to the distribution characteristics.

Numerical simulation and testing of laser-MIG hybrid-welding angle-structure sheets

Numerical simulation and experimental investigation of laser-MIG hybrid angle-welding low-carbon 1.5-mm-thin SPCC steel sheets are presented in this work. The transient simulation analysis provides an access to the thermal-fluid phenomena prediction by employing a hybrid three-dimensional heat source model. Special attention is paid to the melt dynamic behaviors within the triangular molten pool affected by the Marangoni convection. The simulation results show that the temperature and its gradient distribution are symmetrical with respect to the laser beam, which is validated well by the experimental study. The microstructure of the welded joints was analyzed by scanning electron microscopy and transmission electron microscopy. The results show that the cross-section microstructures of welded joint are mainly composed of the weld zone, narrow heat-affected zone, and substrate. The semielliptic-like molten pool shape is consistent with that of the simulated results. The finer microstructure in the weld bead results from the rapid cooling rate of laser welding confirmed by the FEM calculation. The columnar and equiaxed dendrites are formed in the peripheral and central region of the molten pool, which is beneficial for the improvement of the microhardness.

[Influencing factors of futile recanalization after endovascular therapy in acute ischemic stroke patients with large vessel occlusions]

Objective: To analyze the influencing factors of futile recanalization after endovascular therapy (EVT) in acute ischemic stroke patients with large vessel occlusions (AIS-LVO). Methods: AIS-LVO patients who underwent EVT with successful recanalization between January 2019 and December 2021 in Neurovascular Center of Changhai Hospital of Naval Medical University were retrospectively selected. Modified Rankin scale (mRS) score 3 months after EVT was used as the prognostic evaluation index, and patients with mRS scores≤2 were classified as the meaningful recanalization group and mRS scores 3-6 as the futile recanalization group. The risk factors, National Institutes of Health stroke scale (NIHSS) score, Glasgow coma scale (GCS) score, Alberta Stroke Program Early CT (ASPECT) score, core infarct volume, etc. in both groups were analyzed, and the influencing factors of futile recanalization after EVT were analyzed by multivariate logistic regression. Continuous variables that do not conform to the normal distribution are represented by [M(Q1,Q3)]. Results: A total of 368 patients meeting the inclusion criteria were collected, including 228 males and 140 females, and aged 68 (61, 77) years. There are 196 patients and 172 patients in the meaningful recanalization and futile recanalization groups, respectively, with the rate of futile recanalization 3 months after EVT of 46.74% (172/368). Comparing the general information and risk factors between the two groups found that the age of patients in the futile recanalization group [71 (65, 79) years] was higher than that in the meaningful recanalization group [65 (59, 72) years]. The baseline NIHSS score [18 (14, 22)] and the rate of not achieving modified Thrombolysis in Cerebral Ischemia grade 3 (mTICI 3) reperfusion (36.1%) were higher in the futile recanalization group than those in the meaningful recanalization group [12 (7, 17) and 19.9%]. The baseline GCS score [11 (9, 13)] was lower in the futile recanalization group than that in the meaningful recanalization group [14 (11, 15)]. The core infarct volume in the futile recanalization group [28 (7, 65) ml] was larger than that in the meaningful recanalization group [6 (0, 17) ml]. The ASPECT score [7 (5, 9)] was lower in the futile recanalization group than that in the meaningful recanalization group [9 (7, 10)]. In addition, the proportion of hypertension, atrial fibrillation, general anesthesia, and symptomatic intracranial hemorrhage was higher in the futile recanalization group (all P<0.05). The time from symptom onset to puncture and from symptom onset to reperfusion was longer in the futile recanalization group (both P<0.05). There were statistically significant differences in trial of Org 10172 in acute stroke treatment (TOAST) classification and the site of occluded blood vessels between the two groups (both P<0.05). Multivariate logistic regression indicated that age ≥80 years(OR=1.935,95%CI: 1.168-3.205), baseline NIHSS score (OR=1.999,95%CI: 1.202-3.325), GCS score (OR=2.299,95%CI: 1.386-3.814), previous stroke history (OR=1.977,95%CI: 1.085-3.604), general anesthesia (OR=1.981,95%CI: 1.143-3.435), not achieving grade 3 recanalization (OR=2.846, 95%CI: 1.575-5.143), ASPECT score<6 (OR=2.616, 95%CI: 1.168-5.857), and core infarct volume>70 ml (OR=2.712, 95%CI: 1.130-6.505) were risk factors for futile recanalization. Conclusion: Age≥80 years, previous stroke history, baseline NIHSS score≥20, GCS score≤8, general anesthesia, ASPECT score<6, core infarct volume>70 ml, and failure to achieve Grade 3 recanalization are independent influencing factors for futile recanalization after endovascular therapy in AIS-LVO patients.

[Analysis of factors associated with futile recanalization after endovascular treatment for acute ischemic stroke with large vessels occlusion in anterior intracranial circulation]

Objective: To analyze the related factors of futile recanalization (FR) after emergency endovascular treatment of large artery occlusion in anterior circulation. Methods: Three studies on endovascular treatment of acute anterior circulation large vessels occlusion stroke were selected, and their data were merged for retrospective analysis. Patients were divided into the FR group and favorable prognosis group according to the functional prognosis. Risk factor analysis was conducted using multivariate logistic regression. Results: A total of 1 581 patients were finally included, with 858 (48.9%) patients in favorable prognosis group and 926 (51.91%) patients in FR group. Among them, there were 939 males and 642 females, with a mean age of (65±12) years. Multivariate logistic regression analysis showed that National Institute of Health Stroke Scale (NIHSS) score (OR=1.089,95%CI:1.066-1.113), puncture to recanalization time (OR=0.756, 95%CI:0.586-0.971), age (OR=1.04,95%CI:1.029-1.051), serum glucose (OR=1.101,95%CI:1.062-1.143), systolic blood pressure (OR=1.005,95%CI:1.001-1.010), passes≥3(OR=1.941,95%CI:1.294-2.941)Alberta stroke program early CT (ASPECT) score (OR=0.919,95%CI:0.847-0.996), occlusion site (M1 segment of middle cerebral artery, OR=0.744,95%CI:0.565-0.980) and collateral circulation [(2 points, OR=0.757, 95%CI:0.581-0.985); (3-4 points, adjusted OR=0.640, 95%CI: 0.472-0.866)] were independent factors of FR. Conclusion: The incidence of FR in patients with large artery occlusion in anterior circulation who achieve satisfied reperfusion after endovascular treatment is high. Higher NIHSS score, longer puncture to recanalization time, older age, higher serum glucose and systolic blood pressure are risk factors, while lower ASPECTS, occlusion in cerebral middle M1 segment, better collateral circulation are protective factors.

Comparison between ultrasound-guided pericapsular nerve group block and anterio quadratus lumborum block for total hip arthroplasty: a double-blind, randomized controlled trial

OBJECTIVE

Peripheral nerve block can provide effective postoperative analgesia to patients undergoing total hip arthroplasty (THA). This study aimed to compare ultrasound-guided pericapsular nerve group (PENG) block against anterior quadratus lumborum (AQL) block for pain management in primary THA.

PATIENTS AND METHODS

In this prospective, double-blind, randomized controlled trial, 90 patients undergoing primary THA under general anesthesia were randomly allocated to receive ultrasound-guided PENG block + sham AQL block ("PENG group") or ultrasound-guided AQL block + sham PENG block ("AQL" group). The primary outcome was the highest pain score on a visual analogue scale while the patient was in the recovery room. Secondary outcomes included pain scores after transfer out of the recovery room, morphine consumption, quadricep strength, duration of hospitalization, pain level one year after surgery, and incidence of complications.

RESULTS

Patients in the PENG group reported significantly lower maximum pain scores in the recovery room (31.3±9.1 vs. 37.3±7.4, p=0.001), as well as significantly lower pain scores at rest at 3 h after surgery and during motion at 3 and 6 h after surgery. The two groups did not differ significantly in postoperative morphine consumption, length of hospitalization, pain level at one year after surgery, or incidence of complications. Neither block significantly weakened the quadriceps.

CONCLUSIONS

PENG block may provide slightly more effective postoperative analgesia than AQL block during the early recovery period after primary THA.

Pulmonary arteries segmentation from CT images using PA-Net with attention module and contour loss

BACKGROUND

Pulmonary embolism is a kind of cardiovascular disease that threatens human life and health. Since pulmonary embolism exists in the pulmonary artery, improving the segmentation accuracy of pulmonary artery is the key to the diagnosis of pulmonary embolism. Traditional medical image segmentation methods have limited effectiveness in pulmonary artery segmentation. In recent years, deep learning methods have been gradually adopted to solve complex problems in the field of medical image segmentation.

PURPOSE

Due to the irregular shape of the pulmonary artery and the adjacent-complex tissues, the accuracy of the existing pulmonary artery segmentation methods based on deep learning needs to be improved. Therefore, the purpose of this paper is to develop a segmentation network, which can obtain higher segmentation accuracy and further improve the diagnosis effect.

METHODS

In this study, the pulmonary artery segmentation performance from the network model and loss function is improved, proposing a pulmonary artery segmentation network (PA-Net) to segment the pulmonary artery region from 2D CT images. Reverse Attention and edge attention are used to enhance the expression ability of the boundary. In addition, to better use feature information, the channel attention module is introduced in the decoder to highlight the important channel features and suppress the unimportant channels. Due to blurred boundaries, pixels near the boundaries of the pulmonary artery may be difficult to segment. Therefore, a new contour loss function based on the active contour model is proposed in this study to segment the target region by assigning dynamic weights to false positive and false negative regions and accurately predict the boundary structure.

RESULTS

The experimental results show that the segmentation accuracy of this proposed method is significantly improved in comparison with state-of-the-art segmentation methods, and the Dice coefficient is 0.938 ± 0.035, which is also confirmed from the 3D reconstruction results.

CONCLUSIONS

Our proposed method can accurately segment pulmonary artery structure. This new development will provide the possibility for further rapid diagnosis of pulmonary artery diseases such as pulmonary embolism. Code is available at https://github.com/Yuanyan19/PA-Net.

Association between serum asprosin and diabetic peripheral neuropathy in patients with type 2 diabetes mellitus in the community

OBJECTIVE

This study aimed to investigate the relationship between serum asprosin level and diabetic peripheral neuropathy (DPN) in community patients with type 2 diabetes mellitus (T2DM).

PATIENTS AND METHODS

A total of 498 patients with T2DM were recruited from Zhuoma Community Health Service Station and Chengbei West Street Community Health Service Center in Changzhi City of Shanxi Province between November 2019 and July 2021. Their height, weight, and body mass index (BMI), as well as fasting plasma glucose (FPG), glycosylated hemoglobin (HbA1c), triglyceride (TG), and serum asprosin levels, were analyzed. Patients were divided into the DPN group (n = 329) and the non-DPN group (n = 169) according to the presence or absence of DPN. The t-test, Mann-Whitney U test, and χ² test were used to compare the indicators between the two groups. Pearson or Spearman correlation analysis was used to evaluate the correlation between serum asprosin and other clinical data. Multivariate logistic regression analysis was used to analyze the influencing factors of DPN.

RESULTS

Compared with the non-DPN group, the DPN group had higher serum asprosin (p < 0.05). The prevalence of DPN gradually increased according to the tertiles of asprosin (56%, 67%, and 75%; p < 0.05). Multivariate logistic regression analysis showed that after adjustment for covariates, patients with asprosin concentrations between 295.4-367.0 pg/ml and concentrations > 367.0 pg/ml had a higher risk of diabetic neuropathy compared than those with asprosin levels < 295.4 pg/ml (p < 0.05).

CONCLUSIONS

Serum asprosin was found to be positively correlated with DPN, and it resulted as an influencing factor for DPN in patients with T2DM in the community. With the increase of asprosin, the risk of DPN also increased.

Addressing the Global Expertise Gap in Radiation Oncology: The Radiation Planning Assistant

PURPOSE

Automation, including the use of artificial intelligence, has been identified as a possible opportunity to help reduce the gap in access and quality for radiotherapy and other aspects of cancer care. The Radiation Planning Assistant (RPA) project was conceived in 2015 (and funded in 2016) to use automated contouring and treatment planning algorithms to support the efforts of oncologists in low- and middle-income countries, allowing them to scale their efforts and treat more patients safely and efficiently (to increase access).

DESIGN

In this review, we discuss the development of the RPA, with a particular focus on clinical acceptability and safety/risk across jurisdictions as these are important indicators for the successful future deployment of the RPA to increase radiotherapy availability and ameliorate global disparities in access to radiation oncology.

RESULTS

RPA tools will be offered through a webpage, where users can upload computed tomography data sets and download automatically generated contours and treatment plans. All interfaces have been designed to maximize ease of use and minimize risk. The current version of the RPA includes automated contouring and planning for head and neck cancer, cervical cancer, breast cancer, and metastases to the brain.

CONCLUSION

The RPA has been designed to bring high-quality treatment planning to more patients across the world, and it may encourage greater investment in treatment devices and other aspects of cancer treatment.

Antiferromagnetic Spin Fluctuations and Unconventional Superconductivity in Topological Superconductor Candidate YPtBi Revealed by ^{195}Pt-NMR

We report ^{195}Pt nuclear magnetic resonance (NMR) measurements on topological superconductor candidate YPtBi, which has broken inversion symmetry and topological nontrivial band structures due to the strong spin-orbit coupling. In the normal state, we find that Knight shift K is field- and temperature independent, suggesting that the contribution from the topological bands is very small at low temperatures. However, the spin-lattice relaxation rate 1/T_{1} divided by temperature (T), 1/T_{1}T, increases with decreasing T, implying the existence of antiferromagnetic spin fluctuations. In the superconducting state, no Hebel-Slichter coherence peak is seen below T_{c} and 1/T_{1} follows T^{3} variation, indicating the unconventional superconductivity. The finite spin susceptibility at zero-temperature limit and the anomalous increase of the NMR linewidth below T_{c} point to a mixed state of spin-singlet and spin-triplet (or spin-septet) pairing.