Comparison of Estimated Late Toxicities between IMRT and IMPT when Treating Retroperitoneal Sarcoma Preoperatively with Ultra-Hypofractionation

PURPOSE/OBJECTIVE(S)

While preoperative radiation did not improve abdominal recurrence-free survival for retroperitoneal sarcoma (RPS) in the randomized STRASS trial, it did reduce rates of local recurrence. The risk of radiation-associated toxicity is substantial, with 77% of irradiated patients experiencing grade ≥3 lymphopenia in STRASS. Thus, finding methods to mitigate the issues of delaying surgery and irradiating normal tissue may provide a path towards affording the benefits of radiation while limiting its downside. One potential solution involves the use of hypofractionation to limit delay from radiation initiation to surgery, and proton therapy to limit dose to surrounding organs at risk (OARs). We conducted a dosimetric comparison of preoperative ultra-hypofractionated intensity-modulated photon radiotherapy (IMRT) and proton therapy (IMPT) for RPS, comparing estimated rates of late toxicity using published normal tissue complication probability (NTCP) models.

MATERIALS/METHODS

Volumetric modulated arc therapy IMRT and IMPT plans were generated on 10 RPS patients previously treated with preoperative radiation. The prescription was 25 Gy radiobiological equivalent (GyE) to the clinical target volume (CTV) and 30 GyE to the margin-at-risk, all in five fractions. Proton doses were calculated using a radiobiological effective dose of 1.1. NTCPs were calculated for each OAR as a function of equivalent uniform dose. The ΔNTCP (difference in absolute NTCP between IMRT and IMPT plans) for each of the toxicity domains was calculated. Student T-tests were used to compare differences in dosimetric and NTCP outcomes.

RESULTS

CTV coverage was met for all IMRT and IMPT plans with >99% of CTVs receiving ≥100% of prescription doses. The following endpoints were significantly lower with IMPT than IMRT: mean doses to liver, bone, and all analyzed genitourinary and gastrointestinal OARs; bowel, kidney, and bone V5-V20; stomach V15; liver V5; maximum doses to stomach, spinal canal, and body; and whole-body integral dose. No OAR endpoint was significantly higher with IMPT. The average ΔNTCP for grade 3 bowel ulceration/perforation and renal toxicity was 1.9% (p = .037) and 43.0% (p = .023), respectively, favoring IMPT. Using a model-based selection threshold of any ΔNTCP >10%, 50% (n = 5) of patients would be eligible for IMPT.

CONCLUSION

IMPT maintained target coverage while significantly reducing dose to adjacent OARs and integral dose compared to IMRT. This translated to significantly lower risks of estimated late gastrointestinal and renal toxicities with IMPT. Further investigation is warranted to validate these findings and potential clinical benefit in the management of RPS. A prospective trial treating RPS with preoperative ultra-hypofractionated IMPT at our institution is currently being pursued (NCT05302570).

Sarcopenia as a Predictor of Neoadjuvant Therapy-Related Toxicity in Esophageal Squamous Cell Carcinoma Patients

PURPOSE/OBJECTIVE(S)

Sarcopenia, characterized by loss of muscle mass, plays a critical role in patients with esophageal squamous cell cancer (ESCC). Preoperative chemoradiotherapy and immunotherapy in ESCC patients has been reported to improve survival. Therefore, we sought to evaluate the predictive value of preoperative sarcopenia for toxicity and pathological tumor response to neoadjuvant therapy (NAT) in ESCC patients.

MATERIALS/METHODS

A retrospective analysis was performed using a prospectively collected patient cohort of an academic cancer center diagnosed with cT2-4N0-3M0 ESCC between 2019-2022 and treated with neoadjuvant chemoradiotherapy ± pembrolizumab. Sarcopenia was assessed by skeletal muscle index at the third lumbar vertebra in computed tomography scans before NAT (men: 43cm²/m² for body mass index (BMI) < 25kg/m², 53cm²/m² for BMI≥25 kg/m²; women: 41cm²/m²). Logistic regression was performed to assess the association between sarcopenia and preoperative therapy-related toxicity and tumor response.

RESULTS

The study included 59 locally advanced ESCC patients (53 male and 6 female), 48 (81.4%) in the non-sarcopenia group, and 11 (18.6%) in the sarcopenia group. Mean age at diagnosis was 62±8 years. Mean BMI at diagnosis was 22.13±2.85 kg/m². 19 patients (32.2%) were stage ⅢA, 25 patients (42.4%) were ⅢB, 15 patients (25.4%) were ⅣA. No significant differences were found between both groups regarding sex, age, BMI, and clinical stage. Acute grade ≥3 toxicity occurred significantly more frequently in the sarcopenia group (54.5% vs. 22.9%, p = 0.045), which mainly included leukopenia, neutropenia, anemia and thrombocytopenia. The discontinuation of NAT owing to toxicity occurred in 8 patients (13.5%), which was significantly associated with sarcopenia (p = 0.003). All patients proceeded to surgery and 33 patients (55.9%) had a pathological complete response (pCR). Univariate analysis revealed no significant association between sarcopenia and pCR (p = 0.071).

CONCLUSION

Among patients with locally advanced EC, sarcopenia is not a predictor of poor NAT response, but it is strongly associated with discontinuation of NAT due to toxicity.

First Implementation of Full-Workflow Automation for Online Adaptive Radiotherapy of Nasopharyngeal Carcinoma

PURPOSE/OBJECTIVE(S)

The aim of this work is to established the technical characteristics and implementation procedures of an artificial intelligence (AI)-powered radiotherapy workflow that enables full-process automation for online adaptive radiotherapy (ART); and evaluate its feasibility and performance implemented for ART of nasopharyngeal carcinoma (NPC).

MATERIALS/METHODS

This single center, prospective study has been approved by the ethical committee of the institution. The online ART workflow was developed based on a CT-integrated linear accelerator. During the course of radiotherapy, the patient underwent daily pre-treatment fan-beam CT (FBCT) scan. Then the FBCT was automatically registered to the original planning CT and used to assess the need for the patient to implement ART according to radiation oncologist's discretionary. The online ART workflow incorporates critical radiotherapy procedures from re-simulation, auto-segmentation by integrating image fusion and deep learning method, auto-replanning, beam delivery, and in vivo quality assurance (QA) into one scheme, while the patient is on the treatment couch during the whole process.

RESULTS

From 2th April 2022 to 5th January 2023, 20 patients with newly-diagnosed, non-metastatic NPC were enrolled in this study. Only one-time online ART was performed for each patient, because that the appropriate timing for triggering online ART was explored in parallel with this study. According to radiation oncologists' discretionary, the median fraction for performing online ART was at 21 fractions (interquartile range, 19-24 fractions). All patients were well tolerated and successfully completed the treatment. For tumor targets contouring, minor revisions were required for automated contours of the primary gross tumor volume (GTVp) and clinical target volumes (CTVs, including CTV1 and CTV2), with the mean DSC between before and after revision of 0.91±0.042, 0.94 ± 0.042 and 0.91 ± 0.061, respectively; and much more revisions for the automated contours of cervical lymph nodes GTV (GTVn), with the mean DSC of 0.74 ± 0.28. The automated contours of normal tissues were clinically acceptable with little modifications. Median time consuming for auto-segmentation and revision was 9.5 minutes (min). For treatment planning, 18 automated plans (90%) were passed at their first auto-optimization and two plans (10%) were passed after further optimization of the dose coverage of CTVs by physicist; and the median time consuming for auto-planning was 6.2 min. Time consuming for other procedures were as follows: re-simulation, 2.3 min; plan evaluation, 3.3 min; beam delivery, 4.6 min; and the duration of the entire process was 25.9 min, range from 19.4 min to 32.5 min.

CONCLUSION

We successfully established an AI-powered online ART workflow for adaptive radiotherapy of NPC, and confirmed that current auto-segmentation and auto-replanning methods are powered enough to support the clinical application of its online ART.

Inaugural Experience with Real-time Gated Liver Proton SBRT and Treatment Plan Quality Improvement

PURPOSE/OBJECTIVE(S)

DIBH SBRT is routinely used for liver proton therapy. While intra-fraction target motion is limited with DIBH, acquisition of DIBH CT simulations in triplicate, as is done at our institution, reveals that variation does exist between each DIBH scan. The related target position can also vary correspondingly. The most common setup uncertainty for robust proton SBRT liver plan used at our institution is 5 mm sup-inf (SI) and 3 mm radially. Real-time gated proton therapy (RGPT) has the potential to provide instantaneous feedback for intra-fraction target motion to maximize patient safety and inform optimal treatment planning. Our first RGPT liver SBRT with intra-fraction motion under deep inspiration breath hold (DIBH). The potential treatment plan quality improvement brought by RGPT is investigated.

MATERIALS/METHODS

The following metrics were used in establishing our RGPT proton DIBH SBRT liver program: the iso center is always set at the fiducial mark; the beam orientation is selected to achieve both good plan quality and tracking performance; daily CBCTs are acquired and verified using fiducial maker position with kV images; robust uncertainty is determined by the gating tolerance; SBRT plan has three beams with uniform dose. Target motion was monitored throughout treatment. To evaluate dose sparing for surrounding OARs, a plan with tighter gating tolerance (3 mm SI and 2 mm radially) is optimized for dosimetric comparison. Statistical analyses were conducted using a programming environment.

RESULTS

Each of the three proton beams were delivered using DIBH over a total of 120-140 seconds. The average beam on time were 61.4, 66.9 and 62.8 seconds. The intra-fraction motion showed that targets could move up to 3 mm within the same DIBH. The motion increased with time. The table details the mean, maximum, standard deviation, and estimated upper 95% of directional shifts for three beams. Based on these results, plan delivery efficiency was maintained even with tighter gating tolerance. The comparison plan with tight gating tolerance showed significantly less dose (-25%) to the stomach in coronal view.

CONCLUSION

RGPT successfully tracked fiducial marker motion for DIBH SBRT liver treatment. Despite target drift during DIBH, the uncertainty of our DIBH SBRT procedure was sufficient to cover target motion throughout treatment. Based on the target drift value, a maximum of 25 seconds for breath hold time should be employed. Utilizing a tighter gating tolerance of 3 mm SI and 2 mm radially has the potential to maintain target coverage while significantly reducing OAR dose. Aggregated RGPT-derived data may provide optimal treatment planning parameters such as variable uncertainty based on target location.

A Modified Robust Nomogram for Predicting the Probability of Pelvic Lymph Node Invasion in Localized Prostate Cancer

PURPOSE/OBJECTIVE(S)

Improved predictive models for the risk of pelvic lymph node invasion (LNI) in localized prostate cancer (PCa) is important in decision making of pelvic lymph node dissection (PLND) or whole pelvic RT (WPRT). We aimed to establish a nomogram with improved robustness (Ruijin model) based on pre-treatment information.

MATERIALS/METHODS

Continuous localized PCa patients with detailed prostate tumor biopsy information, treated with laparoscopic radical prostatectomy and PLND between 2013 and 2022 in single institution were retrospectively reviewed. A multivariable logistic regression model was fitted and represented the basis for a coefficient-based nomogram of predicting LNI. Comparisons between the Ruijin model and the Roach formula were conducted using the receiver operating characteristic-derived area under the curve (AUC), calibration plot, and decision-curve analyses (DCAs).

RESULTS

In total, 624 patients with median age (69.5 year) were included in this analysis. The median number of pelvis lymph nodes removed was 6 (range: 2-30). LNI was found in 35 (5.6%) patients. In the multivariable logistic regression model, total prostate-specific antigen (OR = 1.008, P = 0.025), percentage of cores with the highest-grade PCa (OR = 14.822, P<0.001), clinical stage (III vs. I-II: OR = 7.733, P = 0.008), and biopsy Gleason Grading Group (G3 vs G1-2: OR = 3.152, P = 0.082; G4 vs G1-2: OR = 3.065, P = 0.083; G5 vs G1-2: OR = 5.262, P = 0.008;) were included and formed the basis for the nomogram. The predictive accuracy of Ruijin nomogram in our cohort was 87.7%. Using a cutoff of 4% based on Ruijin nomogram, 395 (63%) PLND would be spared and LNI would be missed in only two (0.5%) patients. The sensitivity, specificity, and negative predictive value associated with the 4% cutoff were 94.3%, 66.7%, and 99.5%, respectively. As compared with the Roach formula, the Ruijin model showed higher AUC (87.7% vs 80.9%, Z = -2.013, P = 0.044), better calibration characteristics, and a higher net benefit at DCA.

CONCLUSION

We developed a novel nomogram for predicting the LNI in localized PCa patients with detailed biopsy information. PLND or WPRT could be avoided in patients with a risk of LNI <4%, so as to spare more than 60% of unnecessary pelvic nodal treatment with a cost of missing only 0.5% LNIs.

Quality and Safety Considerations in Image Guided Radiation Therapy: An ASTRO Safety White Paper Update

PURPOSE/OBJECTIVE(S)

This updated report on image guided radiation therapy (IGRT) is based on a consensus-based white paper previously published by the American Society for Radiation Oncology (ASTRO) addressing patient safety. In the past decade, IGRT technology and procedures have progressed significantly and are now more commonly used. The use of IGRT has now extended beyond high-precision treatments, such as stereotactic radiosurgery and stereotactic body radiation therapy, and into routine clinical practice for many treatment techniques and anatomic sites. Therefore, quality and treatment planning and delivery considerations for these techniques are paramount for patient safety.

MATERIALS/METHODS

In 2021, ASTRO convened an interdisciplinary task force to assess the original IGRT white paper and update content where appropriate. Recommendations were created using a consensus-building methodology, and task force members indicated their level of agreement based on a 5-point Likert scale from "strongly agree" to "strongly disagree." A prespecified threshold of ≥75% of raters who selected "strongly agree" or "agree" indicated consensus.

RESULTS

The IGRT white paper was published (Pract Radiat Oncol. 2022 Dec) and endorsed by the American Association of Physicists in Medicine (AAPM), American Association of Medical Dosimetrists, and American Society of Radiologic Technologists. Since the first IGRT paper was published by ASTRO in 2013, significant technological advancement has taken place. New and updated considerations in personnel requirements, staffing, education and training, equipment and technological requirements, quality management and assurance, IGRT program management, and safety considerations were reported. A 17-point consensus was reached and recommended in 5 areas surrounding program development, quality assurance, quality management, treatment delivery, and vendor engagement (Table 5, Summary of key recommendations).

CONCLUSION

This IGRT white paper builds on the previous version and uses other guidance documents to primarily focus on processes related to quality and safety. IGRT requires an interdisciplinary team-based approach, staffed by appropriately trained specialists, as well as significant personnel resources, specialized technology, and implementation time. A thorough feasibility analysis of resources is required and should be discussed with all personnel before undertaking new imaging techniques. A comprehensive quality-assurance program must be developed to ensure IGRT is performed safely and effectively. As IGRT technologies continue to improve or emerge, existing practice guidelines should be updated regularly according to the latest AAPM Task Group reports. Patient safety in the application of IGRT is everyone's responsibility, and professional organizations, regulators, vendors, and end-users must demonstrate strong commitments to ensure that the highest levels of safety are achieved.

Proton LET Optimization Via Iterative Convex Relaxation Method

PURPOSE/OBJECTIVE(S)

If not optimized, the LET distribution can greatly impact normal tissue toxicity near tumor targets, because the LET often peaks at the distal edge of Bragg peak. LET optimization can account for biological effectiveness of protons during treatment planning, for minimizing biological proton dose and hot spots to normal tissues. However, the LET optimization is nonlinear and nonconvex to solve, which poses a great challenge in optimization. This work will develop an effective LET optimization method via iterative convex relaxation (ICR).

MATERIALS/METHODS

In contrast to the generic nonlinear optimization method, such as Quasi-Newton (QN) method, that does not account for specific characteristics of LET optimization, ICR is tailored to LET modeling and optimization in order to effectively and efficiently solve the LET problem. Specifically, nonlinear dose-averaged LET term is iteratively linearized and becomes convex during ICR, while nonconvex dose-volume constraint and minimum-monitor-unit constraint are also handled by ICR, so that the solution for LET optimization is obtained by solving a sequence of convex and linearized convex subproblems. Since the high LET mostly occurs near the target, a 1cm normal-tissue expansion of clinical target volume (CTV) (excluding CTV), i.e., CTV1cm, is defined to as an auxiliary structure during treatment planning, where LET is minimized.

RESULTS

ICR was validated in comparison with QN for abdomen, lung, and head-and-neck (HN) cases. ICR was effective for LET optimization, as ICR substantially reduced the LET and biological dose in CTV1cm the ring, with preserved dose conformality to CTV. Compared to QN, ICR had smaller LET, physical and biological dose in CTV1cm, and higher conformity index values; ICR was also computationally more efficient, which was about 3 times faster than QN. A lung case is presented in the table, where the quantities from top to bottom are computational time T (unit: second); total objective F, dose objective Fd and LET objective FL (unit: 10-3); conformity index for physical dose CId and biological dose CIb; mean LET L (unit: keV/μm), mean physical dose d and mean biological dose b (in ratio to prescription dose) for CTV1cm; mean LET L (unit: keV/μm), mean physical dose d and mean biological dose b (in ratio to prescription dose; unit: 10-1) for the heart.

CONCLUSION

A LET-specific optimization method based on ICR has been developed for solving proton LET optimization, which has been shown to be more computationally efficient than generic nonlinear optimizer via QN, with better plan quality in terms of LET, biological and physical dose conformality.

Safety and efficacy of the Low-Profile Visualized Intraluminal Support stent in treating intracranial atherosclerotic stenosis

PURPOSE

The performance of the Low-Profile Visualized Intraluminal Support (LVIS) stent deployed following balloon angioplasty is unknown in treating intracranial atherosclerotic stenosis, and this study was to investigate the safety and efficacy of the LVIS stent in treating intracranial atherosclerotic stenosis in the middle cerebral artery M1 segment.

METHODS

Thirty-five patients were enrolled with 35 atherosclerotic stenoses at the M1 segment. The stenosis was about 75% in 16 patients, 80% in 15, and 90% in the rest four. The LVIS stent was used to treat these patients.

RESULTS

The success rate of stenting was 97.1%. The stenting procedure was failed in one patient because of intraprocedural dissection of the stenotic (75%) segment, resulting in a 30-day periprocedural complication rate of 2.9% (1/35). Before stenting, the stenosis rate ranged 75%-90% (mean 78.9%±4.7%), and after stenting, the diameter of the stented segment was significantly (P<0.0001) increased to 1.5-3.4mm (mean 2.1±0.32mm) ranging 68.2%-100% (mean 94.0%±5.8%) of the normal arterial diameter, with the residual stenosis ranging 0-31.8% (median 4.8%, IQR 2.4%-7.3%). Follow-up was performed at 6-20 months (mean 8.5) after stenting. One patient (2.9%) had occlusion of the stented M1 segment with no symptoms, and two patients (5.7%) had slight asymptomatic instent stenosis (40%) at the M1 segment, with the instent restenosis and occlusion rate of 8.6% (3/35).

CONCLUSION

The braided LVIS stent can be safely applied for treatment of intracranial atherosclerotic stenosis in the middle cerebral artery with good safety and efficacy immediately after stenting and at follow-up.

Prediction of Response to Neoadjuvant Chemoradiotherapy Combined with Pembrolizumab in Esophageal Squamous Cell Carcinoma with CT/FDG PET Radiomic Signatures Based on Machine Learning Classification

PURPOSE/OBJECTIVE(S)

PALACE-1 trial has confirm that the addition of pembrolizumab to neoadjuvant chemoradiotherapy (NCRT) improves the pathological complete response(pCR) for esophageal squamous cell carcinoma (ESCC), which might be a novel treatment strategy for ESCC. In the present study, we aim to establish a machine learning model to predict the local response to NCRT+ pembrolizumab for ESCC by using pretreatment 18-fluorodeoxyglucose positron emission tomography (FDG PET) and contrast-enhanced plan CT images.

MATERIALS/METHODS

A total of 65 cases treated with NCRT+ pembrolizumab followed by surgery were prospectively enrolled for analysis from 2019-2022. Each patient contains a contrast-enhanced plan CT and FDG PET images. 52 patients were randomly divided into training set and 13 patients were used as test set. The Extraction of radiomics features was performed using an open-source Python library PyRadiomics automatically. Features were computed according to the radiologist-drawn ROIs on both CT and PET images. In the feature selection stage least absolute shrinkage and selection operator (LASSO) was utilized on CT features and PET features separately. Four different machine learning models were implemented: Support Vector Machine (SVM), Logistic Regression (LR), Random Forest (RF) and XGBoost (XGB). The features selected by LASSO regression were used as model input and the output of the model is "pCR" or "non-pCR". To find the optimal parameter, the 5-fold cross-validation method was used in the training stage. In this study, we use accuracy, sensitivity and specificity as the metrics to evaluate the performance of the model on the testing cohort. The predictive performance of the model was assessed using the area under curve (AUC) of the receiver operating characteristics curve (ROC).

RESULTS

Of the 65 cases treated with NCRT+pembrolizumab, 35 patients archived pCR (53.8%), and 30 archived non-pCR. 1684 radiomics features were extracted from each case, and half of them (842 features) were from CT and others were from PET. Among the machine learning models mentioned above SVM achieves the most promising performance on the evaluation metrics. Accuracy, sensitivity, specificity and AUC score on test set were 0.692, 0.833, 0.571 and 0.786 for CT features and 0.615, 0.667, 0.571 and 0.762 for PET features, respectively. For CT+FDG PET fused features accuracy, sensitivity, specificity and AUC score on test set were 0.769, 0.667, 0.857 and 0.833.

CONCLUSION

In this study, we performed several different machine learning models to predict the response to NCRT+ pembrolizumab among ESCC based on the extracted radiomics features from CT and FDG PET images. The best-performing model based on radiomics features of CT and PET images could identify non-pCR to NCRT + pembrolizumab in EC patients.

Dosimetric Benefits of Online Adaptive Radiotherapy in Nasopharyngeal Carcinoma

PURPOSE/OBJECTIVE(S)

Online adaptive radiotherapy (ART) has the advantage of compensating for potential underdosing to targets and overdosing to organs-at-risk (OARs) caused by variations in patient anatomy and tumor geometry. Artificial intelligence (AI)-assisted rapid generation of new plans makes online ART possible. We aimed to evaluate the dosimetric benefits of online ART on tumor coverage and OARs sparing in nasopharyngeal carcinoma (NPC).

MATERIALS/METHODS

Twenty patients diagnosed with NPC (19 with stage III and 1 with stage II according to the 8th edition of the AJCC/UICC staging system) who underwent definitive radiotherapy or concurrent chemoradiotherapy and received online ART on CT-Linac between April 2022 and December 2022 were included in this study, consisting of 14 males and 6 females with a median age of 48 years (range: 29-68 years). The prescription dose was 6996 cGy/33 fractions for primary gross tumor volume (GTVp), 6600-6996 cGy/33 fractions for gross tumor volume of nodes (GTVn), 6006 cGy/33 fractions for high-risk clinical tumor volume (CTV1), 5412 cGy/33 fractions for low-risk clinical tumor volume (CTV2). The majority of the patients (15/20) received online ART during the fourth to fifth week of their radiotherapy treatment The auto-segmented contours and auto-plan generated by AI were manually reviewed and edited by radiotherapists and physicists. The paired samples t-test was used to compare the dose and volumes metrics of targets and OARs between scheduled plan and online ART plan.

RESULTS

The results of this study showed that compared to the scheduled plan, the online ART plan resulted in significant reductions in the volumes of all targets and 8/12 OARs (temporal lobes, optic nerves, lenses, eyes, parotids, submandibulars, mandibles, and thyroid) (P<0.05). The online ART plan also improved target coverage, with D98% for GTVp in the scheduled plan compared to the online ART plan being 7063.4 ± 76.1 cGy and 7096.1 ± 53.9 cGy (P = 0.1), CTV1 being 6266.7 ± 114.9 cGy and 6208.7 ± 54.7 cGy (P<0.05), and CTV2 being 4142.5 ± 1700.9 cGy and 5416.4 ± 23.8 cGy (P<0.01), respectively. The dose to all 12 OARs was reduced with the use of online ART, with 5/12 OARs showing statistical significance. The D0.03cm3 for the spinal cord in the scheduled plan and online ART plan were 3630.9 ± 197.6 and 3454.1 ± 132.0 cGy; for the temporal lobes were 7075.2 ± 303.0 and 6994.2 ± 345.1 cGy; and 4396.0 ± 2575.0 and for the pituitary were 4214.5 ± 2499.2 cGy. Meanwhile the Dmean for the eyes in the scheduled plan and online ART plan was 769.0 ± 232.0 and 714.8 ± 200.1 cGy; and for the mandibles were 3187.7 ± 211.5 and 3066.0 ± 152.1 cGy.

CONCLUSION

Online ART was effective in protecting most of the OARs in NPC patients, while simultaneously indicating a trend towards enhancing target coverage. This study demonstrated the promising potential of online ART for patients with NPC. This approach will be tested in an upcoming phase III trial.

Impact of Prophylactic Pelvic Lymph Node Irradiation in De-Novo Oligometastatic Prostate Cancer

PURPOSE/OBJECTIVE(S)

To evaluate the impact of prophylactic pelvic nodal irradiation in de-novo oligometastatic prostate cancer treated with radiotherapy (RT) for both primary tumor and all metastatic lesions.

MATERIALS/METHODS

This was a single-center prospective cohort study. De novo oligometastatic prostate cancer patients with RT for both primary tumor and all metastatic lesions were included. Kaplan-Meier method, log rank test and cox regression were used to calculate OS and PFS. PFS included PSA failure, local or distant failure assessed by imaging.

RESULTS

This study analyzed 202 patients from 10/2011 to 1/2022 with median follow-up of 48 months. A total of 126 (62.4%) patients were treated with pelvic lymph node RT. The dose was 47.5 Gy with 1.9 Gy per fraction. Among them, 66 (32.7%) patients were treated with whole pelvic RT (WPRT), which the upper limit was at the aortic bifurcation. 60 (29.7%) patients were treated with mini-WPRT, which the upper limit was at the lower margin of obturator foramen. The incidence of diarrhea (P = 0.038) and leukocyte reduction (P = 0.040) in the WPRT subgroup during radiotherapy was significantly higher than that in the mini-WPRT and non-pelvic RT subgroup. For the whole cohort, the median OS and PFS were not reached. The subgroup analysis showed that the elective pelvic nodal irradiation could improve PFS (P = 0.042). However, there was no difference of PFS between standard WPRT and mini-WPRT.

CONCLUSION

The study suggests that for de-novo oligometastatic prostate cancer, elective pelvic nodal irradiation may improve PFS. For patients who cannot tolerate WPRT, mini-WPRT may be an alternative option. However, it needs to be verified in the prospective RCT study.

Can Advanced Radiotherapy Clinical Trials be Conducted in Resources Limited Countries?

PURPOSE/OBJECTIVE(S)

The Lancet Oncology Commission on Cancer in Sub-Saharan Africa (SSA) highlighted the region's increasing cancer incidence and mortality, and recommended a series of actions to address this growing crisis. One such approach recommended by the Commission to increase access to curative treatment is the use of hypofractionated radiotherapy (HFRT). Here we highlight the barriers and facilitators to launching HFRT in SSA, as identified through the HypoAfrica clinical trial.

MATERIALS/METHODS

HypoAfrica is a longitudinal multi-center clinical trial that was launched in late 2021 at three centers in Nigeria, Tanzania, and South Africa. The goal of HypoAfrica was to assess the feasibility of implementing HFRT for localized prostate cancer in SSA. To date, 155 of 182 subjects have been enrolled in this study. During the last year, a team of radiation oncology professionals from Africa, Europe, Australia, and USA met once every Saturday and reviewed the sites' data to identify the barriers to the implementation of HFRT and find solutions to overcome these challenges. With the intent to expand HFRT trials and practice to new SSA countries and radiotherapy centers, we also conducted an online survey to elucidate the readiness of radiotherapy centers across SSA to perform HFRT.

RESULTS

The major challenge identified by this team was securing high-quality data that will yield statistically significant results. Factors that contribute to quality data are: harmonization of machine and patient-specific quality assurance (QA) procedures across the centers, data quality harmonization, and challenges associated with machine maintenance. Immediate solutions implemented included introduction of low-cost QA tools for patient-specific QA measurements, ongoing training of the site's healthcare professionals, implementation of preventative maintenance for Linacs, and data centralization infrastructure. These actions have resulted in the production of a high-quality, standardized dataset. Planned longer-term solutions to HFRT challenges include implementation of ongoing training, telehealth for remote support and QA, and the creation of an Imaging and Radiation Oncology Core for Africa. The online survey indicated that 61% of respondents' institutions perform HFRT for palliative purposes, emphasizing the readiness of sites in SSA to utilize HFRT for curative purposes.

CONCLUSION

The study serves as a useful guide for increasing access to HFRT treatment in resource-limited settings and for conducting multicenter radiotherapy clinical trials.

Low Incidence of Late Lymphopenia Following Stereotactic Body Radiotherapy for Localized Prostate Cancer

PURPOSE/OBJECTIVE(S)

Stereotactic body radiotherapy (SBRT) is increasing in use for the treatment of localized prostate cancer. The utilization of highly conformal photon therapy such as SBRT may increase the whole-body integral dose. Lymphocytes are very radiation sensitive. This dose increase could lead to unintended consequences such as lymphopenia. Prior studies have shown that lymphopenia following radiation therapy may negatively impact long-term outcomes. This study sought to evaluate the incidence and timeline of chronic lymphopenia following prostate SBRT.

MATERIALS/METHODS

Institutional IRB (IRB#: 2012-1175) approval was obtained. The absolute lymphocyte count was measured 1-2 hours prior to robotic SBRT (35-36.25 Gy in 5 fractions) and at each follow-up (3, 6, 12, 18 and 24 months). Lymphopenia was graded using the CTCAEv.4: Grade 1 (1.0-0.8 k/μl), Grade 2 (0.8-0.5 k/μl), Grade 3 (0.5-0.2 k/μl) and Grade 4 (<0.2 k/μl). Late lymphopenia was defined as lymphopenia occurring 3 or more months post-SBRT.

RESULTS

From 2019 to 2022, 198 localized prostate cancer patients (23 low-, 148 intermediate-, and 27 high-risk according to the D'Amico classification) at a median age of 73.5 years were treated with SBRT (35-36.25 Gy) at Georgetown University Hospital on a prospective clinical trial. Baseline lymphopenia was uncommon: Grade 1 (3.5%), Grade 2 (1.5%) and Grade 3 (0%). The baseline ALC of 1.9 k/μl decreased to 1.5 k/μl at 3 months post-SBRT and then remained stable for the remainder of the two-year follow-up. Overall, 14.6% of men experienced lymphopenia in the two years following SBRT: Grade 1 (7.6%), Grade 2 (6.6%) and Grade 3 (0.5%). No patient experienced Grade 4 lymphopenia.

CONCLUSION

Prostate SBRT leads to a low rate of late lymphopenia with the vast majority of toxicities being low grade. The peak incidence occurred at 3 months post-SBRT. Resolution of lymphopenia occurs in most patients within two years after SBRT. Future studies should explore the possible impact on quality of life and cancer control outcomes.

Exploration of Multiomic Profiles and Biomarkers as Predictors of Neoadjuvant Chemoradiotherapy Responsiveness in Esophageal Squamous Cell Carcinoma

PURPOSE/OBJECTIVE(S)

The current gold standard of care for resectable locally advanced esophageal cancer is neoadjuvant chemoradiotherapy (NCRT) followed by surgery. Given that only 30-40% of patients with esophageal squamous cell carcinoma (ESCC) achieved a pathologic complete response (pCR) following neoadjuvant chemoradiotherapy, it is critical to understand the biological basis of NCRT resistance in esophageal cancer and identify biomarkers for these patients in order to further personalize treatment plans. We aim to depict the biological landscape of ESCC responsiveness and resistance to neoadjuvant chemoradiotherapy.

MATERIALS/METHODS

Endoscopic biopsied specimens of the primary tumors and paired peripheral blood samples were obtained from 24 patients before neoadjuvant chemoradiotherapy and tested for whole exosome sequencing, RNA sequencing, and DIA mass spectrometry. Genomic data were analyzed for significantly mutated genes, copy number alterations, MSI, TMB, and mutational signatures. Transcriptomics and proteomics data were used to examine differentially activated pathways. GSEA and ActivePathways were used for the single omics level and joint multi-omics analysis, respectively. Tumor microenvironment (TME) characteristics were deconvoluted by xCell upon RNA-seq data. Treatment resistance biomarkers were identified and validated in a separate cohort using mIHC.

RESULTS

In the study cohort, 54% (13/24) of the patients achieved pCR. WES data suggested that FBXW7 was more frequently mutated in the pCR group (fisher test p-value = 0.029), and the most significant cytoband loss in the pCR group was 9p21.3 (qval = 0.001). Differences in TMB, MSI, and mutational signatures were not significant between groups. Combined transcriptomics and proteomics analysis revealed that type I interferon signaling pathways and RIG-I-like receptor signaling pathways(p<0.05) were enriched in non-pCR tumors. Esophageal cancer cohort RNA-seq data from TCGA verified the correlation between the genetic variances (FBXW7 mutation and 9p21.3 loss) and the decreased expression of type I interferon signaling pathway genes. In TME analysis, tolerogenic dendritic cells and exhausted T cell signatures were significantly enriched in non-pCR tumors, indicating an immunosuppressive status in treatment resistant patients. Based on proteomics PPI network and differential expression genes from RNA-seq data, a biomarker panel consisted of 12 proteins predictive of non-pCR tumors was identified: STAT1, EIF2AK2, MX1, BST2, TRIM21, SAMHD1, IFI44L, GBP1, PARP14, ISG15, IFIT3, and HLA-B. The expression of selected genes was validated by mIHC in an independent cohort.

CONCLUSION

Through a multiomics approach, we described the biological characteristics of ESCC with distinct responses to neoadjuvant chemoradiotherapy and proposed a panel of 12 proteins as predictive biomarkers for non-pCR patients.

Observation of New Ω_{c}^{0} States Decaying to the Ξ_{c}^{+}K^{-} Final State

Two new excited states, Ω_{c}(3185)^{0} and Ω_{c}(3327)^{0}, are observed in the Ξ_{c}^{+}K^{-} invariant-mass spectrum using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9  fb^{-1}. Five previously observed excited Ω_{c}^{0} states are confirmed, namely Ω_{c}(3000)^{0}, Ω_{c}(3050)^{0}, Ω_{c}(3065)^{0}, Ω_{c}(3090)^{0}, and Ω_{c}(3119)^{0}. The masses and widths of these seven states are measured with the highest precision to date.

Evidence of a J/ψK_{S}^{0} Structure in B^{0}→J/ψϕK_{S}^{0} Decays

An amplitude analysis of B^{0}→J/ψϕK_{S}^{0} decays is performed using proton-proton collision data, corresponding to an integrated luminosity of 9  fb^{-1}, collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. Evidence with a significance of 4.0 standard deviations of a structure in the J/ψK_{S}^{0} system, named T_{ψs1}^{θ}(4000)^{0}, is seen, with its mass and width measured to be 3991_{-10}^{+12} _{-17}^{+9}  MeV/c^{2} and 105_{-25}^{+29} _{-23}^{+17}  MeV, respectively, where the first uncertainty is statistical and the second systematic. The T_{ψs1}^{θ}(4000)^{0} state is likely to be the isospin partner of the T_{ψs1}^{θ}(4000)^{+} state, previously observed in the J/ψK^{+} system of the B^{+}→J/ψϕK^{+} decay. When isospin symmetry for the charged and neutral T_{ψs1}^{θ}(4000) states is assumed, the signal significance increases to 5.4 standard deviations.

Host response of Nicotiana benthamiana to the parasitism of five populations of root-lesion nematode, Pratylenchus coffeae, from China

In a recent survey of nematodes associated with tobacco in Shandong, China, the root-lesion nematode Pratylenchus coffeae was identified using a combination of morphology and molecular techniques. This nematode species is a serious parasite that damages a variety of plant species. The model plant benthi, Nicotiana benthamiana, is frequently used to study plant-disease interactions. However, it is not known whether this plant species is a host of P. coffeae. The objectives of this study were to evaluate the parasitism and pathogenicity of five populations of the root-lesion nematode P. coffeae on N. benthamiana.N. benthamiana seedlings with the same growth status were chosen and inoculated with 1,000 nematodes per pot. At 60 days after inoculation, the reproductive factors (Rf = final population densities (Pf)/initial population densities (Pi)) for P. coffeae in the rhizosphere of N. benthamiana were all more than 1, suggesting that N. benthamiana was a good host plant for P. coffeae.Nicotiana. benthamiana infected by P. coffeae showed weak growth, decreased tillering, high root reduction, and noticeable brown spots on the roots. Thus, we determined that the model plant N. benthamiana can be used to study plant-P. coffeae interactions.

Search for Λ[over ¯]-Λ Baryon-Number-Violating Oscillations in the Decay J/ψ→pK^{-}Λ[over ¯]+c.c

We report on the first search for Λ[over ¯]-Λ oscillations in the decay J/ψ→pK^{-}Λ[over ¯]+c.c. by analyzing 1.31×10^{9}  J/ψ events accumulated with the BESIII detector at the BEPCII collider. The J/ψ events are produced using e^{+}e^{-} collisions at a center of mass energy sqrt[s]=3.097  GeV. No evidence for hyperon oscillations is observed. The upper limit for the oscillation rate of Λ[over ¯] to Λ hyperons is determined to be P(Λ)=[B(J/ψ→pK^{-}Λ+c.c.)/B(J/ψ→pK^{-}Λ[over ¯]+c.c.)]<4.4×10^{-6} corresponding to an oscillation parameter δm_{ΛΛ[over ¯]} of less than 3.8×10^{-18}  GeV at the 90% confidence level.

[Impact of different diagnostic criteria for assessing mild micro-hepatic encephalopathy in liver cirrhosis: an analysis based on a prospective, multicenter, real-world study]

Objective: To compare the differences in the prevalence of mild micro-hepatic encephalopathy (MHE) among patients with cirrhosis by using the psychometric hepatic encephalopathy score (PHES) and the Stroop smartphone application (Encephal App) test. Methods: This prospective, multi-center, real-world study was initiated by the National Clinical Medical Research Center for Infectious Diseases and the Portal Hypertension Alliance and registered with International ClinicalTrials.gov (NCT05140837). 354 cases of cirrhosis were enrolled in 19 hospitals across the country. PHES (including digital connection tests A and B, digital symbol tests, trajectory drawing tests, and serial management tests) and the Stroop test were conducted in all of them. PHES was differentiated using standard diagnostic criteria established by the two studies in China and South Korea. The Stroop test was evaluated based on the criteria of the research and development team. The impact of different diagnostic standards or methods on the incidence of MHE in patients with cirrhosis was analyzed. Data between groups were differentiated using the t-test, Mann-Whitney U test, and χ (2) test. A kappa test was used to compare the consistency between groups. Results: After PHES, the prevalence of MHE among 354 cases of cirrhosis was 78.53% and 15.25%, respectively, based on Chinese research standards and Korean research normal value standards. However, the prevalence of MHE was 56.78% based on the Stroop test, and the differences in pairwise comparisons among the three groups were statistically significant (kappa = -0.064, P < 0.001). Stratified analysis revealed that the MHE prevalence in three groups of patients with Child-Pugh classes A, B, and C was 74.14%, 83.33%, and 88.24%, respectively, according to the normal value standards of Chinese researchers, while the MHE prevalence rates in three groups of patients with Child-Pugh classes A, B, and C were 8.29%, 23.53%, and 38.24%, respectively, according to the normal value standards of Korean researchers. Furthermore, the prevalence rates of MHE in the three groups of patients with Child-Pugh grades A, B, and C were 52.68%, 58.82%, and 73.53%, respectively, according to the Stroop test standard. However, among the results of each diagnostic standard, the prevalence of MHE showed an increasing trend with an increasing Child-Pugh grade. Further comparison demonstrated that the scores obtained by the number connection test A and the number symbol test were consistent according to the normal value standards of the two studies in China and South Korea (Z = -0.982, -1.702; P = 0.326, 0.089), while the other three sub-tests had significant differences (P < 0.001). Conclusion: The prevalence rate of MHE in the cirrhotic population is high, but the prevalence of MHE obtained by using different diagnostic criteria or methods varies greatly. Therefore, in line with the current changes in demographics and disease spectrum, it is necessary to enroll a larger sample size of a healthy population as a control. Moreover, the establishment of more reliable diagnostic scoring criteria will serve as a basis for obtaining accurate MHE incidence and formulating diagnosis and treatment strategies in cirrhotic populations.

[Interventional effect and mechanism of fermentation liquid of Dendrobium officinale leaves on alcoholic hepatitis mice]

Objective: To explore the intervention effect and mechanism of Dendrobium officinale leaf fermentation liquid on alcoholic hepatitis (AH) mice. Methods: Seventy inbred C57BL/6J male mice aged 6-8 weeks were selected and randomly divided into normal group (NG), model group (MG), liquid feed control group (CG), silybum group (SI), low-dose group (DL), medium-dose group (DM), and high-dose group (DH) of Dendrobium officinale fermentation liquid, with 10 mice in each group. NG group was given common feed, CG group was given control feed (LB alcoholic liquid control feed), SI group was given LB alcoholic liquid feed and silybum by gavage, DL, DM and DH groups were given LB alcoholic liquid feed and 25%, 50% and 100% concentration of Dendrobium officinale leaf fermentation liquid by gavage. An AH model was established by feeding LB alcoholic liquid feed for 8 weeks.At week 8, alanine Transaminase (ALT), triglyceride (TG), transferrin (TRF), interleukin (IL)-6, IL-10, and IL-1β, tumor necrosis factor-α(TNF-α), interferon-γ(IFN-γ) were detected in eye blood of mice. Liver tissues were stained with HE, Oil Red O, Prussian blue and immunofluorescence ROS. The contents of glutathione(GSH) and malondialdehyde (MDA) in liver tissue homogenate were detected. To analyze the intervention effect and mechanism of Dendrobium officinale leaf fermentation solution on AH mice, the mRNA and protein relative expression levels of adenylate activated protein kinase (AMPK), AMPKβ1, phosphorylated AMPKβ1 (p-AMPKβ1), tumor suppressor gene p53 (p53), solsolic vector family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GXP4) were detected by polymerase chain reaction (PCR) and Western blot. Results: Compared with MG group, the serum ALT and TG levels in the DL, DM, and DH groups were all reduced [ALT: (45.94±19.85), (45.73±22.62), and (41.68±7.13) vs (75.51±17.76) U/L, respectively; TG: (0.90±0.23), (0.69±0.22) and (0.41±0.20) vs (1.28±0.19) mmol/L, respectively, all P<0.05]; IL-6, IL-1β, TNF-α, IFN-γ were decreased (all P<0.05). The serum TRF and IL-10 levels in the DM and DH groups were increased (all P<0.05). Compared with MG group, the liver tissue MDA of mice in DL, DM and DH groups was decreased [(0.41±0.05), (0.40±0.03), and (0.43±0.14) vs (0.64±0.06)μmol/g, respectively], GSH was increased (all P<0.05). Compared with MG, mRNA expression levels of AMPK (1.36±0.11, 1.61±0.17, 1.68±0.11 vs 0.80±0.12, respectively), SLC7A11 (0.91±0.12, 0.97±0.12, 0.99±0.13 vs 0.60±0.14, respectively) and GPX4 (0.51±0.11, 0.63±0.17, 0.83±0.15 vs 0.42±0.14, respectively) in the liver tissue of DL, DM and DH groups were all increased (all P<0.05). Compared with MG group, DL, DM and DH groups showed the relative expression levels of AMPKβ1, p-AMPKβ1, SLC7A11 and GPX4 were increased in the liver tissue of mice, while the relative expression levels of p53 protein were decreased (all P<0.05). Compared with MG group, DL, DM and DH groups reduced the degree of hepatic steatosis and inflammation in the lobules, while the iron and ROS staining in the liver tissue became lighter. Conclusion: Dendrobium officinale leaf fermentation liquid can alleviate the severity of AH in mice, and its mechanism may be related to the up-regulation of AMPK to inhibiting the p53/SLC7A11/GPX4 mediated Ferroptosis pathway.

Measurement of the Ratios of Branching Fractions R(D^{*}) and R(D^{0})

The ratios of branching fractions R(D^{*})≡B(B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]→D^{*}μ^{-}ν[over ¯]_{μ}) and R(D^{0})≡B(B^{-}→D^{0}τ^{-}ν[over ¯]_{τ})/B(B^{-}→D^{0}μ^{-}ν[over ¯]_{μ}) are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0  fb^{-1} of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ^{-}→μ^{-}ν_{τ}ν[over ¯]_{μ}. The measured values are R(D^{*})=0.281±0.018±0.024 and R(D^{0})=0.441±0.060±0.066, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is ρ=-0.43. The results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the standard model.

[Clinical characteristics and prognosis of patients with therapy-related myelodysplastic syndrome and acute myeloid leukemia arising from malignant tumors]

Objective: To investigate the clinical characteristics, cytogenetics, molecular biology, treatment, and prognosis of patients with therapy-related myelodysplastic syndrome and acute myeloid leukemia (t-MDS/AML) secondary to malignancies. Methods: The clinical data of 86 patients with t-MDS/AML in West China Hospital of Sichuan University between January 2010 and April 2023 were retrospectively analyzed. The clinical characteristics, primary tumor types, and tumor-related therapies were analyzed. Results: The study enrolled a total of 86 patients with t-MDS/AML, including 67 patients with t-AML, including 1 patient with M(0), 6 with M(1), 27 with M(2), 9 with M(3), 12 with M(4), 10 with M(5), 1 with M(6), and 1 with M(7). Sixty-two patients could be genetically stratified, with a median overall survival (OS) of 36 (95% CI 22-52) months for 20 (29.9%) patients in the low-risk group and 6 (95% CI 3-9) months for 10 (14.9%) in the intermediate-risk group. The median OS time was 8 (95% CI 1-15) months in 32 (47.8%) patients in the high-risk group. For patients with non-acute promyelocytic leukemia (APL) and AML, the median OS of the low-risk group was 27 (95% CI 18-36) months, which was significantly longer than that of the non-low-risk group (χ(2)=5.534, P=0.019). All 9 APL cases were treated according to the initial treatment, and the median OS was not reached, and the 1-, 2-, and 3-year OS rates were 100.0%, (75.0±6.2) %, and (75.0±6.2) % respectively. Of the 58 patients with non-APL t-AML (89.7%), 52 received chemotherapy, and 16 achieved complete remission (30.8%) after the first induction chemotherapy. The 1-, 2-, and 3-year OS rates of the non-APL t-AML group were (42.0 ± 6.6) %, (22.9±5.7) %, and (13.4±4.7) %, respectively. The median OS of patients who achieved remission was 24 (95% CI 18-30) months, and the median OS of those who did not achieve remission was 6 (95% CI 3-9) months (χ(2)=10.170, P=0.001). Bone marrow CR was achieved in 7 (53.8%) of 13 patients treated with vineclar-containing chemotherapy, with a median OS of 12 (95% CI 9-15) months, which was not significantly different from that of vineclar-containing chemotherapy (χ(2)=0.600, P=0.437). In 19 patients with t-MDS, the 1-, 2-, and 3-year OS rates were (46.8±11.6) %, (17.5±9.1) %, and (11.7±9.1) % with a median OS of 12 (95% CI 7-17) months, which was not significantly different from that in t-AML (χ(2)=0.232, P=0.630) . Conclusions: Breast cancer, bowel cancer, and other primary tumors are common in patients with t-MDS/AML, which have a higher risk of adverse genetics. Patients with APL had a high induction remission rate and a good long-term prognosis, whereas patients without APL had a low remission rate and a poor long-term prognosis.

Near-Infrared Triggered Self-Accelerating Nanozyme Camouflaged with a Cancer Cell Membrane for Precise Targeted Imaging and Enhanced Cancer Immunotherapy

Although cancer immunotherapy has made encouraging progress, clinical therapeutic efficiency is often modest due to inadequate immunogenicity and immune resistance. Developing promising nanoagents for simultaneously activating tumor-specific immunity and suppressing immune resistance to achieve efficient immunotherapy is still challenging. Herein, we developed a biomimetic nanozyme consisting of a gold nanorod@mesoporous ceria core-shell scaffold with gold nanoparticle deposition and cancer cell membrane camouflage. The nanozyme exhibited near-infrared (NIR)-enhanced GOx-mimicking activity at high temperatures and performed well under hypoxic environments due to an increased in situ oxygen supply. In cancer cells, the nanozyme induced and amplified hyperthermia by triggering self-accelerating cascade reactions to deplete glucose and inhibiting the expression of heat shock protein under NIR irradiation, which can cause mitochondrial dysfunction and redox balance disruption to activate pyroptosis and elicit a robust immune response. Additionally, the immune checkpoint blockade caused by encapsulated JQ1-mediated PD-L1 downregulation synergistically contributed to excellent immune therapeutic effects. Besides, we demonstrated that cancer cell membrane coating endows the nanozyme targeting ability to tumor. The proposed nanozyme will broaden the application of GOx and have the potential as the nanoplatform for imaging-guided and O2-consuming combined treatments.

Measurement of the Prompt D^{0} Nuclear Modification Factor in p-Pb Collisions at sqrt[s_{NN}]=8.16 TeV

The production of prompt D^{0} mesons in proton-lead collisions in both the forward and backward rapidity regions at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=8.16  TeV is measured by the LHCb experiment. The nuclear modification factor of prompt D^{0} mesons is determined as a function of the transverse momentum p_{T}, and the rapidity in the nucleon-nucleon center-of-mass frame y^{*}. In the forward rapidity region, significantly suppressed production with respect to pp collisions is measured, which provides significant constraints on models of nuclear parton distributions and hadron production down to the very low Bjorken-x region of ∼10^{-5}. In the backward rapidity region, a suppression with a significance of 2.0-3.8 standard deviations compared to parton distribution functions in a nuclear environment expectations is found in the kinematic region of p_{T}>6  GeV/c and -3.25 Collapse

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