Introduction: Fear of cancer recurrence (FCR) is a prominent clinical issue among cancer survivors. This study evaluated the effectiveness of the culturally adapted ConquerFear-HK intervention in reducing FCR among Chinese cancer survivors, compared to standard survivorship care. METHODS:This assessor-masked, two-arm parallel randomized controlled trial, was conducted from June 2021 to February 2024. Cantonese- or Mandarin-speaking Chinese cancer survivors scoring ≥13 on the Fear of Cancer Recurrence Inventory Short Form (FCRI-SF) were randomized to either ConquerFear-HK, focusing on attention training, metacognition modification, acceptance, appropriate monitoring behaviour, and goal setting or active control providing standardized, multidisciplinary survivorship care. Primary outcome was changes in FCR assessed by FCRI at prior randomization, immediately post-intervention (T1), 3 months (T2), and 6 months (T3) post-intervention. Intention-to-treat analyses using linear mixed modelling compared outcome changes across time points. This trial was registered at ClinicalTrials.gov (NCT04568226). RESULTS:Of the 175/220 (79.5%) participants recruited, 89 were randomized to ConquerFear-HK and 86 to control. Significant greater FCRI reductions were observed in ConquerFear-HK at T1 (mean difference = -10.66; 95% CI:-20.15, -1.16) and T2 (mean difference = -12.00; 95% CI:-21.90, -2.11) vs. the control (g = 0.33-0.36). No significant between-group differences were found at T3. CONCLUSION:ConquerFear-HK demonstrates promising short-term (3-month) improvements in FCR among Chinese cancer survivors; however, no sustained benefits were found at 6 months. Possible explanations include the high attrition at 6-month follow-up, a potential early ceiling effect, unconscious therapist bias, or an accelerated adaptation effect in the intervention arm that was achieved later by the control group. .

BackgroundAnti-hypertensive drugs have been reported to demonstrate anti-inflammatory and anti-angiogenic effects. This study aims to investigate the association between anti-hypertensive drugs and the prognosis of colorectal cancer (CRC) patients.MethodsClinical data of 1134 CRC patients with hypertensions and the prescription of anti-hypertensive drugs who had undergone curative surgery in our hospital between 2005 and 2015 were retrieved. Their survival data and immune cell population in circulatory blood were compared among different types of anti-hypertensive drugs and overall CRC patients.ResultsThe 5-year overall survival for the antihypertensives-treated patients (65.2%) was higher than the CRC patients in Hong Kong (58.2%). Hydrochlorothiazide (HCTZ) group showed the best prognosis (79.1%) among different antihypertensive drug, particularly for advance stage or elderly patients, which are poor prognostic factors for overall CRC patients, demonstrated an obviously improved prognosis upon HCTZ treatment. Moreover, our data showed the recurrence rate was significantly lower for HCTZ group (18.3%) compared to non-HCTZ group (26.8%) and the reported rate (31%) of CRC patients in Hong Kong. Finally, patients with a lower pre-operative basophil level showed better overall and disease-free survival following HCTZ treatment.ConclusionThis study demonstrated the association of HCTZ treatment with a better prognosis of CRC patients.

Abstract Background Fluoropyrimidines, including 5-fluorouracil and capecitabine, are the most common chemotherapeutic agents for colorectal carcinoma. Although previous studies have suggested varying degrees of cardiotoxicity with these drugs, there is a notable lack of large-scale investigations with appropriate control groups. This study aimed to evaluate cardiovascular outcome among colorectal carcinoma patients treated with fluoropyrimidines. Methods A retrospective propensity score- matched cohort study was conducted in patients diagnosed with colorectal carcinoma between January 1, 1993 and December 31, 2021 at public hospitals in Hong Kong. Cardiovascular outcomes in patients prescribed fluoropyrimidines were compared with controls. Further analyses to compare 5-fluroracil and capecitabine were performed. Results A total of 51,888 colorectal carcinoma patients were identified. After 1:1 propensity score matching, 21,216 patients were included in the final analysis, with 10,608 patients in each group. 1.06% patients experienced a major adverse cardiovascular event (MACE) at 1 year. There was no significant difference in MACE risk between the two groups (HR 0.91, 95% confidence interval (95%CI): 0.70–1.18, p = 0.46). Risk of cardiovascular death was similar between the two groups (HR 1.05, 95%CI: 0.69–1.60, p = 0.82). Subgroup analysis did not demonstrate a statistically significant elevated risk of MACE during fluoropyrimidine use in high-risk patient groups. Further comparison of 5-fluorouracil and capecitabine did not reveal a difference in MACE (0.80% vs. 0.98%; HR 1.09, 95%CI: 0.64–1.85, p < 0.75). Conclusion Fluoropyrimidine use in patients with colorectal carcinoma did not increase the risk of MACE, cardiovascular death, or other specific cardiovascular conditions. There was no significant difference in cardiovascular risk between 5-fluorouracil and capecitabine. Graphical Abstract

Liver metastasis remains a major cause of death in colorectal cancer (CRC). Interactions between tumor cells and components of the tumor microenvironment (TME) are integral to the progression of cancer cell migration and metastatic dissemination. Investigating these cellular dynamics is essential for identifying actionable therapeutic targets. This study employed bioinformatics analysis, IHC, WB, and murine in vivo imaging to delineate the role of SPOCD1 in CRC. Additional in vitro co-culture systems, immunofluorescence, and RNA-seq were utilized to determine how SPOCD1 modulated epithelial-mesenchymal transition (EMT) through cancer-associated fibroblasts (CAFs). Mechanistic insight into SPOCD1-mediated transcriptional regulation of LAMA4 was obtained via dual-luciferase reporter assays, ChIP-qPCR, and Co-IP. SPOCD1 was found to be markedly upregulated in CRC cells and exhibited potent pro-metastatic activity in vivo. Integration of external datasets with experimental validation revealed a strong correlation between SPOCD1 expression and CAFs infiltration in the TME. Further analyses demonstrated that SPOCD1 enhanced CXCL12 expression in CAFs via upregulation of LAMA4, enabling CXCL12 to engage CXCR4 on CRC cells and activate EMT signaling, thereby driving metastasis. This signaling axis was effectively interrupted by CXCR4 inhibitors. Mechanistically, SPOCD1 promoted LAMA4 expression through DNMT1 recruitment, facilitating DNA methylation-dependent transcriptional regulation. This study delineates a SPOCD1-centered interaction network between CRC cells and CAFs in colorectal cancer liver metastasis (CRLM), offering novel molecular candidates for therapeutic intervention in CRLM.

Screening plays a crucial role in the early detection of colorectal cancer, greatly reducing mortality rates. The objective of this study was to identify a non-invasive diagnostic method utilizing serum microRNA expression for the diagnosis of colorectal cancer patients. The study consisted of three stages. In the first stage, 129 patients with colorectal cancer and 129 normal subjects were recruited as the training set for the development of a blood miRNA panel. The second stage involved recruiting 200 patients from each group as the validation cohort. Finally, a blinded study was conducted in the third stage, with 260 patients recruited to determine the predictive value of our miRNA panel. Serum samples were prospectively collected from colorectal cancer patients and normal subjects between 2017 and 2021 at Queen Mary Hospital in Hong Kong. Quantitative PCR was utilized to detect the serum levels of candidate microRNAs, and a multiple linear regression model was employed to formulate a serum microRNA panel for diagnosing colorectal cancer patients. The performance of the panel was evaluated using ROC analysis. Our study showed that the values of three pairs of serum microRNAs, namely miR-106b-5p/miR-1246, miR-106b-5p/miR-16 and miR-106b-5p/miR-21-5p, exhibited statistically significant differences between colorectal cancer patients and normal subjects. A serum microRNA panel formulated from these three pairs of microRNAs demonstrated high accuracy in diagnosing colorectal cancer patients from normal subjects, with an AUC of approximately 0.9. The serum miRNA test proved to be a feasible and promising non-invasive biomarker for the diagnosis of colorectal cancer patients in comparison to normal subjects.

Abstract Background: Colorectal cancer (CRC) is the most prevalent gastrointestinal (GI) cancer and contribute significantly to global cancer deaths. The mechanism of CRC development is a complex multistage process from hyperplastic lesions to the formation of adenomas, followed by the progression into malignancy. Hence, early detection during hyperplastic and adenomatous stages warrants new screening tests for effective interception of malignancy progression. Cadherin-17 (CDH17) is a biomarker characterized by its overexpression in several GI cancers, but restricted expression in intestinal mucosal epithelium of normal tissues. We have developed a blood immunoassay using a panel of RUO grade antibodies that unveiled CDH17 as a potential marker with high detection sensitivity and specificity for detecting adenomas. Our immunoassay is useful in identifying high-risk individuals with adenomas that may develop into CRC, which can significantly improve the diagnostic efficiency of colonoscopy that is currently lacking. Methods: The study recruited 66 patients (54 adenoma and 12 hyperplasia) and 39 normal samples (no abnormality by colonoscopy). CDH17 level in plasma samples were measured using the CDH17 immunoassay. Results: The novel CDH17 diagnostic assay showed an operating dynamic range from 90ng to 123pg. We observed a progressive and significant increase in the circulating CDH17 level from normal samples to the hyperplasia group, followed by the adenoma group (mean: 1.66ng/mL, 3.20ng/mL, 4.93ng/mL, respectively P<0.0001). The assay performance by ROC curve demonstrated an AUC of >0.9, with a sensitivity of 85% and specificity of 86%. NPV and PPV were 84% and 87%, respectively. The assay outperforms two market available FIT-DNA tests at predicting adenomas (Table. 1). Conclusion: The novel CDH17 immunoassay is potentially a powerful tool for the detection of aberrant plasma CDH17 expression, improving the surveillance and the detection of high-risk individuals for CRC. CDH17 immunoassay outperforms market availalble FIT-DNA tests at detecting hyperplasia and adenoma FIT-DNA test 1 FIT-DNA test 2 CDH17 blood immunoassay Age 40-74 Age 50-84 Age 45-93 Sensitivity (%) Advanced adenoma 63.5 42.4 85.0 Non-advanced adenoma (i.e Hyperplasia) Unavailable 17.2 58.3 Specificity (%) Normal control (no abnormality by colonoscopy) 87.1 89.8 86.1 NPV (%) Advanced adenoma Unavailable Unavailable 83.8 Non-advanced adenoma (i.e Hyperplasia) Unavailable Unavailable 86.1 PPV (%) Advanced adenoma Unavailable Unavailable 87.2 Non-advanced adenoma (i.e Hyperplasia) Unavailable Unavailable 58.3 Citation Format: Ng Lui, Felix Hon, Stella Sun, Pauline Leung, David Ho, John Moon Luk, Dominic Chi-Chung Foo. Diagnostic application of a novel blood CDH17 immunoassay in the detection of colorectal adenoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1061.

ABSTRACTBackgroundColorectal cancer (CRC) is a commonly diagnosed malignancy with significant mortality rates worldwide. The identification of robust prognostic biomarkers for prediction of survival outcomes and recurrence can aid disease management and improve patients' quality of living.AimThis study aimed to investigate the prognostic value of cadherin 17 (CDH17) tissue expression in CRC patients by utilizing a standardized automated immunohistochemistry (IHC) platform integrated with a digitalized scoring system.Methods and ResultsIHC was conducted to assess CDH17 expression on tumor tissues obtained from 150 retrospective CRC cases. A computer‐assisted imaging analysis was performed to quantify CDH17 tissue expression using an IHC scoring algorithm known as the Membrane (M) Score. The relationship between CDH17 M Score and clinicopathological factors such as TNM staging, distant metastasis, and recurrence status was analyzed. The prognostic value of CDH17 M Score was determined by Kaplan–Meier curves and Cox regression analysis for overall survival (OS) and recurrence‐free survival (RFS). Comparison of M Score and pathologist visual scoring was made to assess the validity of software‐derived IHC scoring. CDH17 expression, as measured by M Score, was found to be significantly increased in tumor tissues compared to adjacent normal tissues, and its expression is associated with advanced staging and distant metastasis (normal vs. tumor, p = 0.0011; Stages IV vs. I–III, p < 0.0162; with vs. without metastasis, p = 0.0026; Mann–Whitney U test). Prognostic analysis revealed that high CDH17 M Score was associated with poor OS and RFS (OS, p = 0.0118; RFS, p = 0.0021; log‐rank test). Furthermore, multivariate Cox regression analysis identified that CDH17 M Score was an independent prognostic predictor for OS (HR = 2.296, 95% CI = 1.154–4.968, p = 0.0240) and RFS (HR = 2.489, 95% CI = 1.062–6.494, p = 0.0447).ConclusionIncreased CDH17 M Score was associated with advanced tumor staging and poor survival outcomes using an automated IHC system integrated with a digital image analysis software, highlighting CDH17 could serve as an independent prognostic marker for CRC patients.

Background: The dysregulation of gene expression is one of the key molecular features of colorectal cancer (CRC) development. This study aimed to investigate whether such dysregulation is reflected in rectal swab specimens of CRC patients and to evaluate its potential as a non-invasive approach for screening. Methods: We compared the expression level of 14 CRC-associated genes in tumor and adjacent non-tumor tissue of CRC patients and examined the correlation of their levels in tissue with paired rectal swab specimens. The level of these 14 genes in rectal swab specimens was compared among patients with CRC or polyp and control subjects, and the diagnostic potential of each dysregulated gene and the gene panel were evaluated. Results: The expression of CXCR2, SAA, COX1, PPARδ, PPARγ, Groγ, IL8, p21, c-myc, CD44 and CSF1 was significantly higher in CRC, and there was a significant correlation in the levels of most of them between the CRC and rectal swab specimens. In the training study, we showed that CD44, IL8, CXCR2 and c-myc levels were significantly higher in the rectal swab specimens of the CRC patients. Such result was confirmed in the validation study. A panel of these four genes was developed, and ROC analysis showed that this four-gene panel could identify CRC patients with an AUC value of 0.83 and identify overall polyp and precancerous adenoma patients with AUC values of 0.6522 and 0.7322, respectively. Finally, the predictive study showed that the four-gene panel demonstrated sensitivities of 63.6%, 76.9% and 88.9% in identifying overall polyp, precancerous adenoma and CRC patients, respectively, whereas the specificity for normal subjects was 72.2%. Conclusion: The expression of CRC-associated genes in rectal swab specimens reflects the dysregulation status in colorectal tissue, and the four-gene panel is a potential non-invasive biomarker for early precancerous adenoma and CRC screening.

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction Right ventricular apical pacing is associated with adverse outcomes and there is an increasing preference to perform conduction system pacing as it allows for more physiological left ventricular activation. His-bundle pacing is known to be technically challenging and results in higher pacing thresholds and increased rates of lead dislodgement. Left bundle branch area pacing (LBBAP) is an emerging alternative form of conduction system pacing. Purpose We aim to study the acute success rates, short-term stability and safety using steerable catheter and stylet-driven (SD) leads for the purpose of LBBAP. Methods 40 consecutive patients who underwent LBBAP with steerable catheter and SD leads in our center from August 2021 to November 2022 were included in this series. Patients’ demographics, pacing indications, baseline QRS morphologies and duration and left ventricular ejection fraction (LVEF) were analysed. Acute success was defined as achieving stimulation to LV activation time (Stim-LVAT) ≤75ms or incomplete right bundle branch paced morphology in V1 [1, 2]. We also reported any left bundle branch (LBB) potential (if present) and the V6-V1 interpeak interval. All lead parameters and complications in the immediate (1 day) and short-term (1 week and 3-6 months) timeframe were evaluated. Results 40 patients' age (mean 72.75), gender (male 52.5%), body mass index (mean 24.15) and LVEF (mean 52.75%) were analysed. Pacing indications included sinus nodal dysfunction (25%), atrioventricular block (70%), heart failure with failed cardiac resynchronisation therapy (CRT) (2.5%) and atrial fibrillation (AF) requiring atrioventricular node ablation (2.5%). We achieved an acute success rate of 87.5% (5% with left ventricular septal pacing, 5% converted to conventional right ventricular septal pacing, and 2.5% converted to CRT). Reasons for failure to achieve successful LBBAP include persistent left superior vena cava, high pacing thresholds or inability to burrow lead into the septum for acceptable V1 morphology and Stim-LVAT due to resistance encountered during turning of the lead. 51.43% patients of the successful LBBAP patients had LBB potential present and/or interpeak interval >33ms [3]. Immediate and short-term lead parameters were stable and acceptable in all cases. There were no complications (such as lead dislodgement, rise in lead impedance or threshold) reported during the acute and short-term follow-up. Conclusion LBBAP is successful in 87.5% of our cases with use of steerable catheter deploying stylet-driven leads and is proven to be a safe and feasible method for conduction system pacing. Incremental experience with the delivery tools will further improve successful implantation. Longer term follow-up of these patients is needed to determine the long-term safety and stability of LBBAP using steerable catheter and stylet-driven leads.

INTRODUCTION This prospective, single-arm, pragmatic implementation study evaluated the feasibility of a nurse-led symptom-screening program embedded in routine oncology post-treatment outpatient clinics by assessing (1) the acceptance rate for symptom distress screening (SDS), (2) the prevalence of SDS cases, (3) the acceptance rate for community-based psychosocial support services, and (4) the effect of referred psychosocial support services on reducing symptom distress. METHODS Using the modified Edmonton Symptom Assessment System (ESAS-r), we screened patients who recently completed cancer treatment. Patients screening positive for moderate-to-severe symptom distress were referred to a nurse-led community-based symptom-management program involving stepped-care symptom/psychosocial management interventions using a pre-defined triage system. Reassessments were conducted at 3-months and 9-months thereafter. The primary outcomes included SDS acceptance rate, SDS case prevalence, intervention acceptance rate, and ESAS-r score change over time. RESULTS Overall, 2988/3742(80%) eligible patients consented to SDS, with 970(32%) reporting ≥1 ESAS-r symptom as moderate-to-severe (caseness). All cases received psychoeducational material, 673/970(69%) accepted psychosocial support service referrals. Among 328 patients completing both reassessments, ESAS-r scores improved significantly over time (p < 0.0001); 101(30.8%) of patients remained ESAS cases throughout the study, 112(34.1%) recovered at 3-month post-baseline, an additional 72(22%) recovered at 9-month post-baseline, while 43(12.2%) had resumed ESAS caseness at 9-month post-baseline. CONCLUSION Nurse-led SDS programs with well-structured referral pathways to community-based services and continued monitoring are feasible and acceptable in cancer patients and may help in reducing symptom distress. We intend next to develop optimal strategies for SDS implementation and referral within routine cancer care services.

e14651 Background: Colorectal cancer (CRC) is the third most diagnosed malignancy and the second leading cause of cancer-death globally. The identification of robust prognostic markers for risk stratification of CRC would facilitate the accurate selection of high-risk patients for adjuvant therapies, hence improving patients’ survival and quality of living. Cadherin 17 (CDH17) is a validated biomarker for CRC characterized by its overexpression in tumor tissues (Zheng et al., 2021). CDH17 expression in tissue samples can be reliably detected by immunohistochemistry (IHC), which could potentially provide useful information for malignancy monitoring and prognosis. Nevertheless, the implementation of IHC in clinical settings is hindered by the lack of standardized guidelines. In this regard, the present study employed a standardized automated IHC platform and a digitalized sample scoring system to investigate CDH17 tissue expression and examine its clinical prognostic value in CRC. Methods: IHC was performed to assess CDH17 expression on paired tumor and adjacent non-tumor tissues from a cohort of 198 retrospective CRC cases, using the Lic3 antibody and an automated IHC system integrated with AI-digital imaging analysis. The M-score was generated for CDH17 membrane staining according to the formula (1 × % of weakly stained cells + 2 × % moderately stained cells + 3 × % of strongly stained cells)/6. Clinical correlation analysis with TNM, differentiation, and metastasis was determined. The prognostic value of tissue CDH17 was evaluated by Kaplan-Meier curves and Cox regression analyses on patients’ OS and RFS. Comparison of M-score and pathologist visual scoring was made to assess the validity of software-derived IHC scoring. Results: A significantly higher tissue CDH17 level was observed in CRC patients with advanced tumour staging (Early vs. Late stage, p = 0.0493; Mann-Whitney U test) and distant metastasis (p = 0.0188; Mann-Whitney U test). CRC patients with high M-score (M-ScoreHigh; cut-off = 30) were associated with poorer OS and shorter RFS (OS, p = 0.015; RFS, p = 0.018; Log-rank test). Subgroup analysis revealed that M-ScoreHigh in early-stage CRC predicts patients’ disease recurrence of less than 2 years after curative surgery (p = 0.025; Log rank test). Multivariate cox regression analysis showed that CDH17 was an independent prognostic factor for OS (HR = 1.918, 95% CI = 1.001-3.676, p = 0.05). A comparison of software-derived CDH17 M-score with pathologist scoring demonstrated good correlation of 0.7257 (p < 0.0001, n = 36; Pearson correlation). Conclusions: The present study suggests that CDH17 is a potential biomarker of poor prognosis for CRC. Quantification of tissue CDH17 level using a standardized automated IHC platform and digital image analysis could aid in patient stratification which allows efficient treatment strategies for better survival outcomes.

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction Left bundle branch area pacing (LBBAP) is an established form of conduction system pacing. Innovative fluoroscopic imaging technique with use of radio-opaque contrast in the right ventricle or using pre-mapped His potential has been advocated as an acquired road map to assist in implantation of LBBAP(1) lead. Purpose We aim to explore a different technique by cannulating the coronary sinus (CS) with a sheath and wire to provide real-time anatomical guidance of location of the base of the heart to facilitate more effective LBBAP in a consistent fashion. Methods Prior to LBBAP, the body of the CS is cannulated using an AL2 diagnostic angiographic catheter and a 0.035-inch glidewire. The wire is fixated externally, and fluoroscopic image is acquired before proceeding with deployment of the pacing lead onto an optimal ventricular septal position via standard right (RAO 30) and left anterior oblique (LAO 30) views. From August 2021 to October 2022, we enrolled 12 consecutive patients requiring pacemaker for standard indications and explored the CS cannulation method in delivering LBBAP with either steerable catheters or fixed shape sheaths. Thereafter, we analysed and described the success rates, immediate electrical and device parameters, procedural durations, and clinical events. Results 12 patients were studied. The mean age was 75 ± 13.07 years and 6 (50%) patients were male. 1 (8.3%) was for sinus nodal dysfunction, 10 (83.3%) for atrioventricular block and 1 (8.3%) for atrial fibrillation (AF) control with atrioventricular node ablation. Mean left ventricular ejection fraction was 54.17 ± 8.21 % and baseline QRS was 108.08 ± 23.20ms. LBBAP was successful in all 12 patients based on published criteria with a mean paced QRS duration of 115.25 ± 9.28 ms. The mean total procedure duration was 130.75 +/- 29.84 minutes and mean fluoroscopic duration was 23.17 ± 9.11 minutes. After 1st week post implant, the pacing threshold, sensing, and impedances were stable and acceptable in all the patients. There were no acute complications (e.g. pneumothorax, lead complications, lead dislodgements / perforations) during the periprocedural period. Conclusion(s) The CS cannulation method is a feasible, safe, and effective method to to provide real-time anatomical visualisation of the base of the heart. This facilitates the achievement for optimal LBBAP and can be adopted especially in difficult cardiac anatomies or rotated cardiac silhouettes identified on fluoroscopy.

The global pandemic of COVID-19 has led to extensive practice of online learning. Our main objective is to compare different online synchronous interactive learning activities to evaluate students’ perceptions. Moreover, we also aim to identify factors influencing their perceptions in these classes. A cross-sectional, questionnaire-based study focusing on clinical year medical students’ perceptions and feedback was conducted between February 2021 –June 2021 at the University of Hong Kong. Online learning activities were divided into bedside teaching, practical skill session, problem-based learning (PBL) or tutorial, and lecture. A questionnaire based on the Dundee Ready Education Environment Measure (DREEM) was distributed to 716 clinical year students to document their perceptions. One hundred responses were received with a response rate of 15.4% (110/716, including 96 from bedside teaching, 67 from practical skill session, 104 from PBL/tutorial, and 101 from lecture). For the mean score of the DREEM-extracted questionnaire, online PBL/tutorial scored the highest (2.72 ± 0.54), while bedside scored the lowest (2.38 ± 0.68, p = 0.001). Meanwhile, there was no significant difference when we compared different school years (p = 0.39), age (p = 0.37), gender (p = 1.00), year of internet experience (<17 vs ≥17 years p = 0.59), or prior online class experience (p = 0.62). When asked about students’ preference for online vs face-to-face classes. Students showed higher preferences for online PBL/tutorial (2.06 ± 0.75) and lectures (2.27 ± 0.81). Distraction remains a significant problem across all four learning activities. A multivariate analysis was performed regarding students’ reported behavior in comparison with their perception through the DREEM-extracted questionnaire. The results showed that good audio and video quality had a significant and positive correlation with their perception of online bedside teaching, practical skill sessions, and PBL/tutorial. It also showed that the use of the video camera correlated with an increase in perception scores for lectures. The present analysis has demonstrated that students’ perception of different online synchronous interactive learning activities varies. Further investigations are required on minimizing distraction during online classes.

Background: This study assessed the potential cost-effectiveness of high (80–100%) vs low (21–35%) fraction of inspired oxygen (FiO2) at preventing surgical site infections (SSIs) after abdominal surgery in Nigeria, India, and South Africa. Methods: Decision-analytic models were constructed using best available evidence sourced from unbundled data of an ongoing pilot trial assessing the effectiveness of high FiO2, published literature, and a cost survey in Nigeria, India, and South Africa. Effectiveness was measured as percentage of SSIs at 30 days after surgery, a healthcare perspective was adopted, and costs were reported in US dollars ($). Results: High FiO2 may be cost-effective (cheaper and effective). In Nigeria, the average cost for high FiO2 was $216 compared with $222 for low FiO2 leading to a −$6 (95% confidence interval [CI]: −$13 to −$1) difference in costs. In India, the average cost for high FiO2 was $184 compared with $195 for low FiO2 leading to a −$11 (95% CI: −$15 to −$6) difference in costs. In South Africa, the average cost for high FiO2 was $1164 compared with $1257 for low FiO2 leading to a −$93 (95% CI: −$132 to −$65) difference in costs. The high FiO2 arm had few SSIs, 7.33% compared with 8.38% for low FiO2, leading to a −1.05 (95% CI: −1.14 to −0.90) percentage point reduction in SSIs. Conclusion: High FiO2 could be cost-effective at preventing SSIs in the three countries but further data from large clinical trials are required to confirm this.

Colorectal cancer (CRC) is one of the major healthcare problems worldwide. A practical screening tool for advanced polyp, which allows the detection and removal of advanced polyps before developing into cancer, is still under investigation. MicroRNAs (miRNAs) have been suggested to serve as valuable signatures for numerous disease conditions and show higher stability in liquid biopsies. This study aims to identify a panel of serum microRNAs as a potential screening method for advanced colorectal polyp patients.

e15519 Background: Screening is of paramount importance in early colorectal cancer detection which can significantly reduce its mortality. This study aims to identify a non-invasive diagnostic method using serum microRNA expression to diagnose colorectal cancer patients. Methods: Serum samples were prospectively collected from CRC patients or normal subjects during 2017 to 2021 in Queen Mary Hospital of Hong Kong and divided into 3 study cohorts: Training cohort (n = 129 per group), Validation cohort (n = 200 per group) and Prediction cohort (n = 260). Quantitative PCR was applied to detect the serum level of 20 candidate microRNAs. Multiple linear regression was used to formulate a serum microRNA panel for diagnosing CRC patients. The performance was evaluated by ROC analysis. The cost-effectiveness was investigating by comparing the cost of two CRC diagnostic strategies comprising of (i) colonoscopy alone and (ii) microRNA panel and followed by colonoscopy strategies to microRNA panel tested positive patients. Results: The values of 3 pairs of serum microRNAs, including miR-106b/miR-1246, miR-106b/miR-16 and miR-106b/miR-21 showed statistical significant difference between CRC patients and normal subjects. A serum microRNA panel formulated from these 3 pairs of microRNAs was able to diagnose CRC patients from normal subjects with high accuracy for both training cohort [AUC: 0.9078 (95% CI, 0.9122 To 0.9734; p < 0.0001)] and Validation cohort (AUC: 0.8904), suggesting that this microRNA panel had a consistent performance across different patient cohorts. Our prediction cohort showed that this microRNA panel was able to screen CRC patients with 85.8% sensitivity, 80.95% specificity, 86.9% positive predictive value and 79.4% negative predictive value. Cost-effectiveness analysis revealed that the strategy of combining serum miRNA test and colonoscopy was a more cost-effective approach compared to colonoscopy alone. The average cost saved per patient was around HK$4010. Conclusions: The serum miRNA test was a feasible, promising and cost-effective non-invasive biomarker for diagnosing CRC patients from normal subjects.

Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases and its prevalence is increasing worldwide. It is reported that NAFLD is associated with colorectal polyps. Since identifying NAFLD in its early stages could prevent possible disease progression to cirrhosis and decrease the risk of HCC by early intervention, patients with colorectal polyp may thus be considered a target group for screening NAFLD. This study aimed to investigate the potential of serum microRNAs (miRNAs) in identifying NAFLD for colorectal polyp patients. Serum samples were collected from 141 colorectal polyp patients, of which 38 had NAFLD. The serum level of eight miRNAs was determined by quantitative PCR and delta Ct values of different miRNA pairs which were compared between NAFLD and control groups. A miRNA panel was formulated from candidate miRNA pairs by multiple linear regression model and ROC analysis was performed to evaluate its diagnostic potential for NAFLD. Compared to the control group, the NAFLD group showed significantly lower delta Ct values of miR-18a/miR-16 (6.141 vs. 7.374, p = 0.009), miR-25-3p/miR-16 (2.311 vs. 2.978, p = 0.003), miR-18a/miR-21-5p (4.367 vs. 5.081, p = 0.021) and miR-18a/miR-92a-3p (8.807 vs. 9.582, p = 0.020). A serum miRNA panel composed of these four miRNA pairs significantly identified NAFLD in colorectal polyp patients with an AUC value of 0.6584 (p = 0.004). The performance of the miRNA panel was further improved to an AUC value of 0.8337 (p < 0.0001) when polyp patients with other concurrent metabolic disorders were removed from the analysis. The serum miRNA panel is a potential diagnostic biomarker for screening NAFLD in colorectal polyp patients. This serum miRNA test could be performed for colorectal polyp patients for early diagnosis and for prevention of the disease from progressing into more advanced stages.