Spatially Controlled Phase Transition in MoTe2 Driven by Focused Ion Beam Irradiations.

Phase transitions play an important role in tuning the physical properties of two-dimensional (2D) materials as well as developing their high-performance device applications. Here, we reported the observation of a phase transition in few-layered MoTe2 flakes by the irradiation of gallium (Ga+) ions using a focused ion beam (FIB) system. The semiconducting 2H phase of MoTe2 can be controllably converted to the metallic 1T'-like phase via Te defect engineering during irradiations. By taking advantage of the nanometer-sized Ga+ ion probe proved by FIB, in-plane 1T'-2H homojunctions of MoTe2 at submicrometer scale can be fabricated. Furthermore, we demonstrate the improvement of device performance (on-state current over 2 orders of magnitude higher) in MoTe2 transistors using the patterned 1T'-like phase regions as contact electrodes. Our study provides a new strategy to drive the phase transitions in MoTe2, tune their properties, and develop high-performance devices, which also extends the applications of FIB technology in 2D materials and their devices.

Thermal ablation with and without adjuvant systemic therapy: a nationwide multicenter observational cohort study of solitary colorectal liver metastases.

BACKGROUND: Thermal ablation is routinely used for solitary colorectal liver metastases (SCLM), but the added value of adjuvant systemic therapy in SCLM remains unclear. This study aimed to compare the long-term outcomes for SCLM treated by ablation alone (AB) versus ablation plus systemic therapy (AS). METHODS: This multicenter retrospective study using nationwide data from fourteen institutions between October 2010 and May 2023, 369 patients with initial SCLM smaller than 5 cm, no extrahepatic metastases, and colorectal cancer R0 resection treated by thermal ablation were included. The crude analysis was used to analyze eligible cases between the two groups. The propensity score matching (PSM) to control for potential confounders in each matched group. Subgroup analyses were performed to identify specific survival benefits. RESULTS: 61.2% (226/369) of eligible patients were treated with AS and 38.8% (143/369) with AB. During the median follow-up period of 8.8 years, 1-/3-/5-year DFS/OS rates did not differ between the two groups, when analyzed via PSM (P=0.52/0.08). Subgroup analysis revealed that AS was significantly associated with better OS than AB in patients with plasma CEA >5 ug/L (P=0.036), T (III-IV) category of primary cancer (P=0.034), or clinical risk score (1-2) (P=0.041). In each matched group, we did find a significant difference in drug-related adverse events (P<0.001) between AS group (24.1%, 28/116) and AB group (0.0%, 0/116). CONCLUSIONS: For patients with plasma CEA >5 ug/L, T (III-IV) category of primary cancer, or clinical risk score (1-2), thermal ablation plus systemic therapy appeared to be associated with improved overall survival. Thermal ablation was equally effective in disease-free survival for treating solitary colorectal liver metastasis, whether with or without adjuvant systemic therapy.

Acute kidney injury comorbidity analysis based on international classification of diseases-10 codes.

OBJECTIVE: Acute kidney injury (AKI) is a clinical syndrome that occurs as a result of a dramatic decline in kidney function caused by a variety of etiological factors. Its main biomarkers, serum creatinine and urine output, are not effective in diagnosing early AKI. For this reason, this study provides insight into this syndrome by exploring the comorbidities of AKI, which may facilitate the early diagnosis of AKI. In addition, organ crosstalk in AKI was systematically explored based on comorbidities to obtain clinically reliable results. METHODS: We collected data from the Medical Information Mart for Intensive Care-IV database on patients aged [Formula: see text] 18 years in intensive care units (ICU) who were diagnosed with AKI using the criteria proposed by Kidney Disease: Improving Global Outcomes. The Apriori algorithm was used to mine association rules on the diagnoses of 55,486 AKI and non-AKI patients in the ICU. The comorbidities of AKI mined were validated through the Electronic Intensive Care Unit database, the Colombian Open Health Database, and medical literature, after which comorbidity results were visualized using a disease network. Finally, organ diseases were identified and classified from comorbidities to investigate renal crosstalk with other distant organs in AKI. RESULTS: We found 579 AKI comorbidities, and the main ones were disorders of lipoprotein metabolism, essential hypertension, and disorders of fluid, electrolyte, and acid-base balance. Of the 579 comorbidities, 554 were verifiable and 25 were new and not previously reported. In addition, crosstalk between the kidneys and distant non-renal organs including the liver, heart, brain, lungs, and gut was observed in AKI with the strongest heart-kidney crosstalk, followed by lung-kidney crosstalk. CONCLUSION: The comorbidities mined in this study using association rules are scientific and may be used for the early diagnosis of AKI and the construction of AKI predictive models. Furthermore, the organ crosstalk results obtained through comorbidities may provide supporting information for the management of short- and long-term treatment practices for organ dysfunction.

Evaluation of transrectal ultrasound-guided tru-cut biopsy as a complementary method for predicting pathological complete response in rectal cancer after neoadjuvant treatment: a phase II prospective and diagnostic trial.

IMPORTANCE: Patients with pathological complete response (pCR) of rectal cancer following neoadjuvant treatment had better oncological outcomes. However, reliable methods for accurately predicting pCR remain limited. OBJECTIVE: To evaluate whether transrectal ultrasound-guided tru-cut biopsy (TRUS-TCB) adds diagnostic value to conventional modalities for predicting pathological complete response in patients with rectal cancer after neoadjuvant treatment. DESIGN, SETTING, AND PARTICIPANTS: This study evaluated data of patients with rectal cancer who were treated with neoadjuvant treatment and reassessed using TRUS-TCB and conventional modalities before surgery. This study is registered with ClinicalTrials.gov. MAIN OUTCOMES AND MEASURES: The primary outcome was accuracy, along with secondary outcomes including sensitivity, specificity, negative predictive value, and positive predictive value in predicting tumour residues. Final surgical pathology was used as reference standard. RESULTS: Between June 2021 and June 2022, a total of 74 patients were enroled, with 63 patients ultimately evaluated. Among them, 17 patients (28%) exhibited a complete pathological response. TRUS-TCB demonstrated an accuracy of 0.71 (95% CI, 0.58-0.82) in predicting tumour residues. The combined use of TRUS-TCB and conventional modalities significantly improved diagnostic accuracy compared to conventional modalities alone (0.75 vs. 0.59, P =0.02). Furthermore, TRUS-TCB correctly reclassified 52% of patients erroneously classified as having a complete clinical response by conventional methods. The occurrence of only one mild adverse event was observed. CONCLUSIONS AND RELEVANCE: TRUS-TCB proves to be a safe and accessible tool for reevaluation with minimal complications. The incorporation of TRUS-TCB alongside conventional methods leads to enhanced diagnostic performance.

Numerical study on the characteristics of roadway failure and instability in coal seam with rock parting.

In order to explore the mechanism of rockburst in coal seam with rock parting, a combination of on-site and numerical experiment is used to study the failure and instability process, crack propagation mechanism, and influencing factors. The following four points were addressed: (1) the instability is a process that roadway in coal seam with rock parting go through from stable locking in the initial stress unloading stage to slipping unlocking, and then to spatter ejection in slipping dynamic load disturbance stage. (2) The fracture development caused by unloading excavation of coal seam with rock parting will change from shear crack to tensile crack. In this process, coal-rock contact surface slip and coal-rock fracture are coupled with each other. (3) The greater the mining depth is, the greater the lateral pressure coefficient is, and the higher the rockburst risk is. On the contrary, the lower the risk of rockburst. (4) When choosing the support form of roadway in coal seam with rock parting, the two supporting forms of bolting (cable) and supplementary masonry support should be preferred. The results enrich the theory of the dynamics of surrounding rock fracture in coal mine, further clarify the potential dangers to mining-area roadways and working faces, and provide technical information to ensure the safe and efficient mining of bifurcated coal seam.

Contrast-enhanced ultrasound with microbubbles containing sulfur hexafluoride and perfluorobutane with Kupffer phase for the detection of colorectal liver metastases.

OBJECTIVE: To compare contrast-enhanced ultrasound (CEUS) with microbubbles containing sulfur hexafluoride (SHF) and perfluorobutane (PFB) for the detection of colorectal liver metastasis (CRLM). METHODS: In this prospective study, conducted from September to November 2021, patients with colorectal cancer were consecutively recruited and underwent same-day ultrasound, SHF-CEUS, and PFB-CEUS. The reference standard was contrast-enhanced MRI and follow-up imaging. The size, depth, echogenicity, and calcification of each focal liver lesion were recorded. The number and conspicuity of CRLMs, based on washout appearance during the late phase (LP) (> 120 s)/Kupffer phase (KP), were evaluated offsite by two blinded readers. RESULTS: Overall, 230 lesions (CRLMs, n = 219; benign lesions, n = 11) in 78 patients were evaluated. Lesion conspicuity (p = 0.344) and accuracy in the detection of CRLM were comparable for SHF- and PFB-CEUS (0.877 for SHF vs. 0.770 for PFB, p = 0.087). More CRLMs ≥ 10 mm were identified by LP contrast washout in SHF-CEUS than in KP PFB-CEUS (p < 0.001). More CRLMs < 10 mm were identified by KP washout in PFB-CEUS than in LP SHF-CEUS (p < 0.001). Conspicuity was better on PFB-CEUS than on SHF-CEUS (p = 0.027). In hyperechoic lesions, lesions located deeper than 80 mm, and calcified lesions, CRLM conspicuity on PFB-CEUS was inferior to that on SHF-CEUS (p < 0.05). CONCLUSIONS: The overall accuracy of detection and conspicuity of washout in CRLMs were comparable between SHF and PFB-CEUS. PFB-CEUS has the advantage of identifying washout in small CRLMs. However, larger, hyperechogenic, deep-seated, or calcified lesions were better identified using SHF-CEUS. CLINICAL RELEVANCE STATEMENT: Accuracy of detection and conspicuity of washout in CRLMs were comparable between SHF- and PFB-CEUS. PFB-CEUS has the advantage in detecting small CRLMs, whereas SHF-CEUS is better for detecting larger, hyperechogenic, deep-seated, or calcified lesions. KEY POINTS: Contrast-enhanced ultrasound with sulfur hexafluoride in the late phase and perfluorobutane microbubbles in the Kupffer phase were comparable in terms of accuracy in the detection and conspicuity of colorectal liver metastases. Small colorectal liver metastases (< 10 mm) were more often identified in the Kupffer phase contrast-enhanced ultrasound imaging when using perfluorobutane microbubbles. Larger, hyperechogenic, deep-seated, or calcified lesions were better identified in the late phase contrast-enhanced ultrasound imaging (> 120 s) when using sulfur hexafluoride microbubbles.

Inflammatory mesenteric fat detected by Intestinal ultrasound is correlated with poor long-term clinical outcomes in patients with Crohn's disease.

BACKGROUND: Data on the correlation between inflammatory mesenteric fat (i-fat), detected by intestinal ultrasound (IUS), and the prognosis of Crohn's disease (CD) remains limited. AIMS: To investigate the impact of IUS-detected i-fat on long-term clinical outcomes. METHODS: We retrospectively enrolled 171 active CD patients who initiated infliximab. Clinical remission (CR), mucosal healing (MH) and transmural healing (TH) were assessed at week-14 and 1 year. RESULTS: Baseline i-fat was detected in 107 patients, while 64 without i-fat. At week-14 and 1 year, patients with i-fat showed lower rates of CR (61.7% vs. 87.5%; 62.3% vs. 86.7%), MH (20.6% vs. 46.9%; 38.6% vs. 65.0%) and TH (10.3% vs. 31.3%; 21.6% vs. 51.7%), compared to those without (all p<0.01). Multivariable analysis revealed that baseline i-fat was a negative predictor for CR (OR=0.212) and MH (OR=0.425) at week-14, and CR (OR=0.340) and TH (OR=0.364) at 1 year (all p<0.05). At week-14, 56 patients with baseline i-fat recovered to without i-fat. Patients with i-fat recovery had higher rates of CR (86.8% vs. 23.1%), MH (58.5% vs. 7.7%) and TH (34.0% vs. 2.6%) at 1 year than those with i-fat at week-14 (all p<0.001). CONCLUSION: IUS-detected i-fat correlated poor long-term clinical outcomes in CD with infliximab.

Percutaneous ablation of colorectal liver metastases: a comparison between the outcomes of grayscale US guidance and Sonazoid CEUS Kupffer phase guidance using propensity score matching.

PURPOSE: To assess the utility of Sonazoid contrast-enhanced ultrasound (CEUS) for guiding percutaneous microwave ablation (MWA) for colorectal liver metastases (CRLMs). MATERIALS AND METHODS: The medical records of patients who had undergone ultrasound (US)-guided percutaneous MWA between July 2020 and June 2022, were reviewed. Propensity score matching (PSM) with a ratio of 1:1 was used to balance the potential bias between the grayscale US-guided and Sonazoid CEUS-guided groups. Local tumor progression (LTP), intrahepatic recurrence (IR), and complication rates were compared between the two groups. RESULTS: Of 252 patients enrolled, 247 achieved complete ablation, and the technical effectiveness was 98.0% (247/252). Of these 247 patients, 158 were in the grayscale US-guided group and 89 in the Sonazoid CEUS-guided group. The median follow-up period was 14.6 months. After PSM, there were no significant differences in LTP, IR, or complication rates between the two groups (p = 0.100, p = 0.511, p > 0.99, respectively). Multivariate analysis identified tumor size ≥ 3 cm (hazard ratio [HR], 7.945; 95% CI, 2.591-24.370; p < 0.001), perivascular (HR, 2.331; 95% CI, 1.068-5.087; p = 0.034), and tumor depth > 8 cm (HR, 3.194; 95% CI, 1.439-7.091; p = 0.004) as significant factors associated with LTP. For tumors with poor vision on grayscale US, Sonazoid CEUS-guided ablation achieved a better LTP rate than grayscale US-guided ablation (3.7% vs.14.8%, p = 0.032). CONCLUSION: For tumors with poor vision on grayscale US, Sonazoid CEUS guidance is recommended for better local tumor control.

Colitis cystica profunda: A report of two cases.

Colitis cystica profunda (CCP) is a rare benign disease characterized by mucus-filled cysts in the submucosa. Endoscopic, radiological and histological examinations are not highly specific, which can lead to misdiagnosis, resulting in unnecessary radical surgical resection. This report presents two cases of CCP with their clinical and imaging features.

Baseline and Postinduction Intestinal Ultrasound Findings Predict Long-term Transmural and Mucosal Healing in Patients With Crohn's Disease.

BACKGROUND: Intestinal ultrasound (IUS) is becoming a standard assessment tool in Crohn's disease (CD), but limited data exist on its ability to predict long-term objective outcomes. Therefore, we aimed to investigate the predictive value of IUS findings for long-term transmural healing (TH) and mucosal healing (MH) in CD. METHODS: We prospectively included consecutive CD patients with active endoscopic disease and bowel wall thickness (BWT) >3.0 mm, initiating infliximab. Intestinal ultrasound parameters (ie, BWT, inflammatory mesenteric fat [i-fat], bowel blood flow and stratification) and International Bowel Ultrasound Segmental Activity Score (IBUS-SAS) were collected at baseline, after 14 to 26 weeks (visit 1, postinduction) and 44 to 56 weeks (visit 2). Transmural healing (normalization of all IUS parameters) and MH (SES-CD ≤2) were assessed at visit 2. RESULTS: One hundred twenty-nine patients were evaluated. At visit 2, 38.0% and 48.1% of patients achieved TH and MH, respectively. All the IUS parameters and IBUS-SAS showed improvement at visit 1 and visit 2 compared with the baseline (all P < .001). Multivariable analysis found that presence of i-fat at baseline (odds ratio [OR], 0.57; P = .008) and greater postinduction BWT (OR, 0.24; P < .001) were negative predictors for TH, while higher baseline (OR, 0.98; P = .013) and postinduction (OR, 0.94; P < .001) IBUS-SAS predicted negatively for MH. Postinduction BWT <4.5mm best predicted TH (AUC 0.85; P < .001), while postinduction IBUS-SAS <25.0 best predicted MH (AUC 0.82; P < .001). Moreover, colonic disease was associated with higher risk of TH (OR, 2.55; P = .027), and disease duration >24 months with lower risk of MH (OR, 0.27; P = .006). CONCLUSIONS: Baseline and postinduction IUS findings reliably predict long-term TH and MH in patients with CD receiving infliximab.

Baseline and postinduction intestinal ultrasound findings reliably predict long-term transmural and mucosal healing in patients with Crohn's disease receiving infliximab. International Bowel Ultrasound Segmental Activity Score is responsive to treatment.

MRI-based brain age prediction model for children under 3 years old using deep residual network.

Early identification and intervention of abnormal brain development individual subjects are of great significance, especially during the earliest and most active stage of brain development in children aged under 3. Neuroimage-based brain's biological age has been associated with health, ability, and remaining life. However, the existing brain age prediction models based on neuroimage are predominantly adult-oriented. Here, we collected 658 T1-weighted MRI scans from 0 to 3 years old healthy controls and developed an accurate brain age prediction model for young children using deep learning techniques with high accuracy in capturing age-related changes. The performance of the deep learning-based model is comparable to that of the SVR-based model, showcasing remarkable precision and yielding a noteworthy correlation of 91% between the predicted brain age and the chronological age. Our results demonstrate the accuracy of convolutional neural network (CNN) brain-predicted age using raw T1-weighted MRI data with minimum preprocessing necessary. We also applied our model to children with low birth weight, premature delivery history, autism, and ADHD, and discovered that the brain age was delayed in children with extremely low birth weight (less than 1000 g) while ADHD may cause accelerated aging of the brain. Our child-specific brain age prediction model can be a valuable quantitative tool to detect abnormal brain development and can be helpful in the early identification and intervention of age-related brain disorders.

Outcomes Following Different Thermal Ablation Strategies in Patients with Unresectable Colorectal Liver Metastases.

Background For patients with unresectable colorectal liver metastases (CRLM), clinical guidelines recommend imaging-guided thermal ablation combined with systemic therapy. However, the optimal thermal ablation strategy remains unclear. Purpose To compare long-term outcomes between patients who underwent upfront ablation or delayed ablation for unresectable CRLM. Materials and Methods This retrospective study included patients with unresectable CRLM (three or fewer lesions; diameter, <3 cm) admitted to one of seven hospitals between October 2009 and December 2020. Upfront ablation was performed 2-4 weeks before the start of systemic therapy, and delayed ablation was performed 2-3 months after the start of systemic therapy. Propensity score matching was applied to adjust for differences in baseline variables between groups. Disease-free survival (DFS) was the primary outcome. Overall survival (OS), complications, and adverse events were secondary outcomes. Outcomes were compared between groups by using the log-rank test. Results In total, 255 patients who underwent delayed ablation (mean age, 57 years ± 11 [SD]; 184 men [72%]) and 103 patients who underwent upfront ablation (mean age, 56 years ± 12; 72 men [70%]) were included. After propensity score matching (n = 100 in both groups), the 5-year DFS for patients who underwent upfront ablation was better compared with patients who underwent delayed ablation (36% vs 21%; P = .02). For 5-year OS, no evidence of a difference was observed between ablation strategies (delayed ablation, 59% vs upfront ablation, 64%; P = .49). Additionally, no differences were observed between ablation strategies with respect to the rates of ablative complications (delayed ablation, 6% vs upfront ablation, 5%; P = .76) or drug-related adverse events (delayed and upfront ablation both 9%; P = .99). Conclusion In patients with relatively few (three or fewer) and small (<3 cm) unresectable CRLM, upfront thermal ablation combined with adjuvant systemic therapy led to better DFS compared with delayed ablation. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Georgiades in this issue.

In Situ Self-Assembled J-Aggregate Nanofibers of Glycosylated Aza-BODIPY for Synergetic Cell Membrane Disruption and Type†I Photodynamic Therapy.

The in situ self-assembly of exogenous molecules is a powerful strategy for manipulating cellular behavior. However, the direct self-assembly of photochemically inert constituents into supramolecular nano-photosensitizers (PSs) within cancer cells for precise photodynamic therapy (PDT) remains a challenge. Herein, we developed a glycosylated Aza-BODIPY compound (LMBP) capable of self-assembling into J-aggregate nanofibers in situ for cell membrane destruction and type I PDT. LMBP selectively entered human hepatocellular carcinoma HepG2 cells and subsequently self-assembled into intracellular J-aggregate nanovesicles and nanofibers through supramolecular interactions. Detailed studies revealed that these J-aggregate nanostructures generated superoxide radicals (O2 - ⋅) exclusively through photoinduced electron transfer, thus enabling effective PDT. Furthermore, the intracellular nanofibers exhibited an aggregation-induced retention effect, which resulted in selective toxicity to HepG2 cells by disrupting their cellular membranes and synergizing with PDT for powerful tumor suppression efficacy in vivo.

α-Stereoselective 3-Deoxy-d-manno-oct-2-ulosonoic Acid (Kdo) O-Glycosylation with a p-Toluenethioglycoside Donor by the (p-Tol)2SO/Tf2O Preactivation Strategy.

A convenient and efficient approach was developed to synthesize α-Kdo O-glycosides based on the Tf2O/(p-Tol)2SO preactivation strategy using peracetylated Kdo thioglycoside as a donor. Under the optimized reaction conditions, several O-glycoside products, including α-(2 → 1)-, α-(2 → 2)-, α-(2 → 3)-, and α-(2 → 6)-Kdo products, were stereoselectively synthesized in high yields. Remarkably, a series of aromatic α-Kdo O-glycosides were first and successfully constructed in high yields. An SN2-like mechanism was revealed by DFT calculations and experimental results.

Quasi-One-Dimensional ZrS3 Nanoflakes for Broadband and Polarized Photodetection with High Tuning Flexibility.

Two-dimensional (2D) layered materials with low crystal symmetries have exhibited unique anisotropic physical properties. Here, we report systematic studies on the photoresponse of field effect transistors (FETs) fabricated using quasi-one-dimensional ZrS3 nanoflakes. The as-fabricated phototransistors exhibit a broadband photocurrent response from ultraviolet to visible regions, where the responsivity and detectivity can be enhanced via additional gate voltages. Furthermore, benefiting from the strong in-plane anisotropy of ZrS3, we observe a gate-voltage and illumination wavelength-dependent polarized photocurrent response, while its sub-millisecond-time response speed is also polarization-dependent. Our results demonstrate the flexible tunability of photodetectors based on anisotropic layered semiconductors, which substantially broadens the application of low symmetry layered materials in polarization-sensitive optoelectronic devices.

Identification of Distinct Clinical Phenotypes of Heterogeneous Mechanically Ventilated ICU Patients Using Cluster Analysis.

This retrospective study aimed to derive the clinical phenotypes of ventilated ICU patients to predict the outcomes on the first day of ventilation. Clinical phenotypes were derived from the eICU Collaborative Research Database (eICU) cohort via cluster analysis and were validated in the Medical Information Mart for Intensive Care (MIMIC-IV) cohort. Four clinical phenotypes were identified and compared in the eICU cohort (n = 15,256). Phenotype A (n = 3112) was associated with respiratory disease, had the lowest 28-day mortality (16%), and had a high extubation success rate (~80%). Phenotype B (n = 3335) was correlated with cardiovascular disease, had the second-highest 28-day mortality (28%), and had the lowest extubation success rate (69%). Phenotype C (n = 3868) was correlated with renal dysfunction, had the highest 28-day mortality (28%), and had the second-lowest extubation success rate (74%). Phenotype D (n = 4941) was associated with neurological and traumatic diseases, had the second-lowest 28-day mortality (22%), and had the highest extubation success rate (>80%). These findings were validated in the validation cohort (n = 10,813). Additionally, these phenotypes responded differently to ventilation strategies in terms of duration of treatment, but had no difference in mortality. The four clinical phenotypes unveiled the heterogeneity of ICU patients and helped to predict the 28-day mortality and the extubation success rate.

Prevalent Pseudoprogression and Pseudoresidue in Patients With Rectal Cancer Treated With Neoadjuvant Immune Checkpoint Inhibitors.

BACKGROUND: Immune checkpoint inhibitor (ICI) treatment in patients with microsatellite instability-high/mismatch repair deficient (MSI-H/dMMR) tumors holds promise in reshaping organ preservation in rectal cancer. However, the benefits are accompanied by distinctive patterns of response, introducing a dilemma in the response evaluation for clinical decision-making. PATIENTS AND METHODS: Patients with locally advanced rectal cancer with MSI-H/dMMR tumors receiving neoadjuvant ICI (nICI) treatment (n=13) and matched patients receiving neoadjuvant chemoradiotherapy (nCRT; n=13) were included to compare clinical response and histopathologic features. RESULTS: Among the 13 patients receiving nICI treatment, in the final radiologic evaluation prior to surgery (at a median of 103 days after initiation of therapy), progressive disease (n=3), stable disease (n=1), partial response (n=7), and complete response (n=2) were observed. However, these patients were later confirmed as having pathologic complete response, resulting in pseudoprogression and pseudoresidue with incidences of 23.1% (n=3) and 76.9% (n=10), respectively, whereas no pseudoprogression was found in the 13 patients receiving nCRT. We further revealed the histopathologic basis underlying the pseudoprogression and pseudoresidue by discovering the distinctive immune-related regression features after nICI treatment, including fibrogenesis, dense lymphocytes, and plasma cell infiltration. CONCLUSIONS: Pseudoprogression and pseudoresidue were unique and prevalent response patterns in MSI-H/dMMR rectal cancer after nICI treatment. Our findings highlight the importance of developing specific strategies for response evaluation in neoadjuvant immunotherapy to identify patients with a good response in whom sphincter/organ-preserving or watch-and-wait strategies may be considered.

Up-Front Versus Delayed Thermal Ablation for Colorectal Liver Oligometastases: A Multicenter Retrospective Study Using Propensity Score Matching.

BACKGROUND. Thermal ablation combined with systemic therapy is an accepted treatment of colorectal liver oligometastases (CLOM). Consensus is lacking regarding the optimal timing of thermal ablation relative to systemic therapy. OBJECTIVE. The purpose of our study was to compare delayed and up-front thermal ablation in terms of efficacy and safety in the treatment of patients with CLOM. METHODS. This retrospective multicenter study included 440 patients (316 men, 124 women; mean age, 57.1 ± 11.1 [SD] years) with CLOM from nine hospitals between October 2009 and December 2020. Patients underwent delayed (n = 322) or up-front (n = 118) thermal ablation in combination with systemic therapy. Analyses included all patients using crude data, all patients using inverse probability treatment weighting (IPTW), and a subset of patients using propensity score matching (PSM) at a 1:1 ratio to balance baseline variables (108 matched patients for each group [i.e., delayed ablation and up-front ablation]). Patients were classified as having a low or high tumor burden score (TBS) on the basis of the number and size of the liver metastases. The primary outcome was progression-free survival (PFS); secondary outcomes included overall survival (OS), complications from ablation, and adverse events (AEs) from systemic therapy. Survival analysis used the Kaplan-Meier method. RESULTS. The median follow-up was 2.9 years. The 5-year PFS was 17.1% for delayed ablation versus 33.6% for up-front ablation in all patients and 17.9% versus 34.7% after PSM. Delayed ablation was associated with worse PFS in the crude analysis (HR = 0.62), IPTW analysis (HR = 0.66), and PSM analysis (HR = 0.62) (all p < .05). No analysis showed a significant difference in OS between delayed and up-front ablation. Crude, IPTW, and PSM analyses showed better PFS for up-front compared with delayed ablation in patients with a low TBS (HR = 0.62-0.67; all p < .05); none of these analyses showed significant difference in PFS in patients with a high TBS. Delayed ablation and up-front ablation groups showed no difference in frequency of grade III or IV ablation complications (4.7% vs 6.8%, p = .38) or grade III or IV systemic therapy AEs (12.4% vs 10.2%, p = .53). CONCLUSION. In patients with CLOM, up-front ablation achieved better PFS compared with delayed ablation, although only among patients with a low TBS. CLINICAL IMPACT. These findings could help optimize clinical implementation of thermal ablation in patients who are not candidates for surgical resection.

Malignant transformation of rectal endometriosis: Preoperative diagnosis by endorectal ultrasound guided biopsy.

The prevalence of malignant transformation of endometriotic lesions is estimated between 0.3% and 1%. Malignant transformations of endometriosis occur in the colorectum is rarer, accounting for 0.25%. Because the malignant transformation of colorectal endometriosis rarely involves mucosa, it is difficult to obtain abnormal tissue by routine endoscopic biopsy. In this case, we evaluated a patient with a rectal mass by endorectal ultrasound (ERUS) and performed endorectal ultrasound-guided biopsy (EGB). Malignant transformations of endometriosis were confirmed by histological result. For patients with rectal tumors but with negative findings on colonoscopy and biopsy, ERUS and EGB contribute to preoperative diagnosis.