Introduction

Motorized spiral enteroscopy (MSE) has shown to be safe and effective for deep small bowel enteroscopy in patients with and without prior abdominal surgery, including patients with Crohn’s disease.
This case series reports our first results regarding the feasibility and safety of the MSE with endoscopic balloon dilatation in patients with small bowel strictures due to Crohn’s disease.

Aims & Methods

Data were collected retrospectively on patients who underwent MSE for endoscopic balloon dilatation of small bowel strictures due to Crohn’s disease. Strictures were either postoperative (P.O.) or post-inflammatory (P.I.).

Results

A total of ten consecutive patients with Crohn’s disease underwent 13 procedures. Propofol sedation without endotracheal intubation was used in all procedures. Demographic and procedure related data are shown in the table. One patient underwent three procedures with 3–4 month intervals. During the third procedure triamcinolone acetonide was injected at four quadrants of the stricture. Fluorescence imaging was used during six procedures. The procedure was technically successful in 12/13 of procedures. In one case, dilatation was not performed because of a longer than anticipated and a sharply angulated stricture.
The number of treated strictures ranged from one to five per procedure. Dilatation of multiple strictures in two patients (4 and 5) was achieved within a relatively short procedure duration of 55 and 70 minutes. Two retained video capsules were retrieved.
Besides the anticipated mild abdominal discomfort and/or sore throat in three patients, no adverse events occurred.

	Patients (age/F/M)	Type stenosis	Procedure route	No. of strictures/ Location (cm)		Maximal dilatation (mm)	Procedure duration (min)	Fluorescence imaging (+/-)
1	44/M	P.O	Antegrade	1/ 200 cm from Treitz		15/18/18 *	50/45/40*	+/+/-
2	54/F	P.I. and VCE retention	Ante-/retrograde	4/ 300 cm from Treitz/ 150 cm from ICV		15	70	+
3	56/F	Mixed	Antegrade	5/ 150-180 cm from Treitz		18	55	-
4	25/M	P.I. and VCE retention	Antegrade	1/ 100 cm from Treitz		18	35	+
5	26/M	P.O.	Ante-/retrograde	1/ 120 cm from Treitz/280 cm from ICV		18 mm via retrograde route	45	-
6	23/F	P.O.	Ante-/retrograde	1/ 450 cm from Treitz/ 50 cm from ICV		15 mm of ileo-ileal anastomosis (pinpoint)	80	+
7	33/M	P.O.	Ante-/retrograde	1/ 350 cm from Treitz /100 cm from ICV		18 mm via retrograde	60	-
8	52/M	P.O.	Antegrade	1/ 200		18	30	-
9	50/F	P.I.	Retrograde	1/ 100		18	30	+

*= 3 Procedures; P.O= Postoperative; P.I= Post-inflammatory; VCE= Video capsule endoscope; ICV= Ileocecal valve
NB: data on patient number 10 is not shown in the table because of the limited number of rows (10) allowed. No dilatation was done.

Conclusion

These retrospective data show that MSE with CRE dilatation is feasible and safe in a cohort of patients with strictures due to Crohn’s disease, postoperatively as well as post-inflammatory. The fact that the distal 16 cm of the endoscope are not covered by the spiral overtube makes cautious introduction of the endoscope beyond a recently dilated stricture feasible and safe. Therefore, dilatation of multiple strictures in one session is possible, provided that they are at a short distance from each other. Fluorescence imaging guidance may be helpful in severe stenosis, multiple strictures, or sharp angulations.

Introduction

Colonic diverticular bleeding (CDB) is the most common cause of acute lower gastrointestinal bleeding (ALGIB). In a recent Japanese multicenter retrospective cohort study, 63.6% of patients with ALGIB were ultimately diagnosed with CDB [1]. It has also been reported that CDB in ALGIB is reportedly more severe than in other entities [2, 3]. However, few reports have demonstrated the efficacy and safety of bowel preparation for patients undergoing urgent colonoscopy.

Aims & Methods

We aim to clarify choice a of bowel preparation for urgent colonoscopy in patients with colonic diverticular bleeding. In a multicenter retrospective cohort study at 10 institutions, we analyzed the endoscopic findings and clinical course of patients diagnosed with CDB who underwent urgent colonoscopy within 24 hours after admission. Bowel preparation consisted of oral consumption of 1 to 2 L of polyethylene glycol lavage (PEL); enemas were not used. We compared those CDB patients who underwent PEL (PEL group) with a control group who did not undergo PEL (non-PEL group) before and after propensity score matching. For the matching, we selected variables known at the time of hospital admission (i.e. age, sex, comorbidities, medications, performance status, and laboratory data). The primary endpoint of the study was length of hospital stay, and secondary endpoints included blood transfusion requirements, rebleeding rates, endoscopic findings, and complications.

Results

242 patients were enrolled in this study. The median age was 76 years, and 60.7% of patients were men (n = 147). Approximately half of the patients underwent bowel preparation with PEL prior to urgent colonoscopy (n = 129). We compared with clinical findings between the PEL and non-PEL groups. The length of hospital stay was shorter in the PEL group (8.0 ± 5.1 days vs 10.9 ± 5.8 days; mean ± SD; P < 0.001). Further, the PEL group was significantly younger (72.2 ± 12.1 vs 75.4 ± 13.1; mean ± SD; P = 0.036), had fewer patients with hypertension (62.0% vs 75.2%; P = 0.027) and malignant neoplasm (1.6% vs 10.6%; P = 0.002), and had better performance statuses (86.1% vs 76.1%; P = 0.047). Patients in the PEL group received fewer blood transfusions (25.6% vs 44.3%; P = 0.002), had a higher rate of cecal completion (88.3% vs 49.6%; P < 0.001), and shorter endoscopic observation times (20.8 ± 16.2 min vs 29.9 ± 24.8 min; mean ± SD; P = 0.006). After propensity score matching, there were 91 patients each in PEL group and in non-PEL group. PEL group had a significantly shorter hospital stay (7.9 ± 4.6 days vs 10.7 ± 5.8 days; mean ± SD; P < 0.001), a higher cecum completion rate (87.8% vs 48.3%; P < 0.001), and a shorter endoscopic observation time (20.7 ± 16.8 min vs 28.9 ± 24.1 min; mean ± SD; P = 0.031) than non-PEL group. There were no significant differences in blood transfusion requirements, rebleeding rates, identification of SRH, need for endoscopic hemostatic treatment, or complication rates.

Conclusion

In patients with CDB, urgent colonoscopy under PEL resulted in shorter hospital stays, higher cecal completion rates, and shorter endoscopic observation time in urgent colonoscopy. The safety of urgent colonoscopy with PEL was comparable to colonoscopy without PEL. These results suggest that PEL is preferrable for urgent colonoscopy in patients with CDB.

References

1. Nagata N, Kobayashi K, Yamauchi A, et al. Identifying bleeding etiologies by endoscopy affected outcomes in 10,342 cases with hematochezia: CODE BLUE-J study. Am J Gastroenterol 2021; 116: 2222-2234.
2. Aoki T, Nagata N, Shimbo T, et al. Development and validation of a risk scoring system for severe acute lower gastrointestinal bleeding. Clin Gastroenterol Hepatol 2016; 14: 1562-1570.e2.
3. Xavier SA, Machado FJ, Magalhães JT, et al. Acute lower gastrointestinal bleeding: are STRATE and BLEED scores valid in clinical practice? Colorectal Dis 2019; 21: 357-364.

Introduction

Recently, artificial intelligence (AI)-based diagnostic support tools for early gastric cancer have been developed and reported to be superior to endoscopists (accuracy: 70% and sensitivity: 85%).¹ However, These tools could not guarantee reliable diagnostic accuracy in clinical practice. In previous reports, magnifying endoscopy has been recognized as superior to white-light imaging endoscopy for endoscopic diagnosis of early gastric cancers. Therefore, we developed an AI-based diagnostic support system using magnifying endoscopy with narrow band imaging (M-NBI) for early gastric cancers² and improved its application in clinical practice using nondegraded images obtained from selective depth inspection (SDI) output for real-time diagnosis. This study is the first to create an AI-based diagnostic support system using non-degraded M-NBI images obtained from SDI output, as several previous papers have analyzed damaged M-NBI images that were converted from various recording devices.^3,4

Aims & Methods

We built a new AI system (M-NBI AI) which was assembled using four different image recognition models with non-degraded M-NBI images (normal mucosa:1776 images, gastric cancers: 1947 images, and non-neoplastic lesions: 2451 images). We evaluated the performance of this M-NBI AI for diagnosis of early gastric cancer. The diagnostic performances of M-NBI AI and endoscopists (five specialists and five non-specialists) were compared using non-degraded M-NBI images (three images per lesion) of 50 early gastric cancer and 50 non-cancerous lesions. Early gastric cancers included histopathological types of well, moderately, and poorly differentiated adenocarcinomas and signet-ring cell adenocarcinomas. The primary outcome was the superiority of the M-NBI AI (based on accuracy) over the endoscopists. The secondary outcome was the superiority of the M-NBI AI (based on sensitivity) over the endoscopists.

Results

	M-NBI AI	Endoscopists
		Specialists	Non-specialists
Accuracy, % (95% CI)	87.0 (0.80–0.94)	80.0 (0.72–0.88)	71.0 (0.62–0.79)
Sensitivity, % (95% CI)	86.3 (0.77–0.96)	74.2 (0.63–0.85)	70.6 (0.58–0.83)
Specificity, % (95% CI)	88.0 (0.79–0.97)	89.0 (0.80–0.99)	71.0 (0.59–0.84)
PPV, % (95% CI)	88.0 (0.79–0.97)	92.0 (0.84–0.99)	72.0 (0.60–0.84)
NPV, % (95% CI)	86.0 (0.76–0.96)	68.0 (0.55–0.81)	70.0 (0.57–0.83)
PPV, positive predictive value; NPV, negative predictive value

The M-NBI AI was superior to the non-specialists based on accuracy (87.0%, 95%CI: 0.80–0.94 versus 71.0 %, 95%CI: 0.62–0.79; p<0.01), without being superior to the specialists (87.0%, 95%CI: 0.80–0.94 versus 80.0%, 95%CI: 0.72–0.88; p=0.18). The M-NBI AI was superior to the specialists and non-specialists based on sensitivity (86.3%, 95%CI: 0.77–0.96 versus 74.2%, 95%CI: 0.63–0.85 and 70.6%, 95%CI: 0.58–0.83; p<0.05, respectively).

Conclusion

The M-NBI AI was created as a new AI system that could be implemented for current endoscopy systems as a real-time diagnostic support tool for early gastric cancers. It demonstrated a robust performance and may indicate equalization of diagnostic accuracy and superadded effect over the white-light endoscopy for diagnosis of early gastric cancers in clinical practice.

References

1. Ishioka M et al. Dig Endosc. 2022. doi: 10.1111/den.14455.
2. Ueyama H et al. J Gastroenterol Hepatol. 2021;36(2):482-489.
3. Horiuchi Y et al. Dig. Dis. Sci. 2020;65:1355–1363.
4. He X et al. Gastrointest Endosc. 2022;95(4):671-678.

Introduction

Postoperative ileus, is one of the most common causes of prolonged hospital stays after abdominal surgery which cause from physiologic hypomotility of the gastrointestinal tract occurring immediately after abdominal surgery. Multi-modal approach to the resolution of postoperative ileus includes ERAS protocol such as opioid minimization, early ambulation, intake of prokinetic drug. Mosapride citrate (mosapride) is known to promote gastrointestinal motility. The objective of this study is to evaluate the effects of mosapride on postoperative ileus and postoperative gastrointestinal motility in patients undergoing elective open and laparoscopic colorectal surgery.

Aims & Methods

The study was approved by ethics committee of the Faculty of Medicine Ramathibodi Hospital Mahidol University (Ref. Number COA.MURA2021/328,ClinicalTrials.gov Identifier: NCT04905147). Forty-four colorectal cancer patients, undergoing open and laparoscopic colorectal surgery in Ramathibodi Hospital during July 2021-August 2022, were randomly assigned to a mosapride group or control group. The mosapride group received 15 mg of mosapride by enteric route with 50 ml of water three times a day, starting on postoperative day 1. The control group received 15 mg of placebo drug with 50 ml of water at the same time. Postoperative time to the first passage of flatus and the first bowel movement were evaluated by one investigator with triple blind study. Time to step diet, length of postoperative hospital stays, and adverse effects were also evaluated in secondary outcomes.

Results

All forty four patients were include, twenty-three in control group and twenty-one in mosapride group. There were no statistically significance differences between mean age and type of surgery (laparoscopic or open) in two group (P>0.05). Time to first bowel movement and time to passage of flatus after operation were significantly shorter in the mosapride group than the control group (26 vs 50 hours, P=0.004 and 40 vs 70 hours, P=0.003, respectively). Time to step diet (soft diet) was also shorter in the mosapride group (90 vs 132 hours, P=0.004). Time to defecate was less in mosapride group than control group (80 vs 120 hours, P <0.001). Length of hospital stay was significantly shorter in patients receiving mosapride (7 vs 10 days, P=0.004).

Conclusion

This study demonstrated the efficacy of mosapride when administered to patients who underwent elective colorectal surgery. Mosapride significantly enhance recovery of gastrointestinal motility and shorter length of hospital stay with no significant adverse effects.

References

1. Collins TC, Daley J, Henderson WH, Khuri SF. Risk factors for prolonged length of stay after major elective surgery. Ann Surg 1999;230:251–9
2. Vather R, O'Grady G, Bissett IP, Dinning PG. Postoperative ileus: mechanisms and future directions for research. Clin Exp Pharmacol Physiol. 2014;41(5):358-370.
3. Goldstein JL, Matuszewski KA, Delaney C, Senagore A, Chiao E, Shah M, et al. Inpatient economic burden of postoperative ileus associated with abdominal surgery in the United States. P AND T.2007;32(2):82.
4. Venara A, Neunlist M, Slim K, Barbieux J, Colas PA, Hamy A, et al. Postoperative ileus: Pathophysiology, incidence, and prevention. J Visc Surg 2016;153:439-46.
5. Luckey A, Livingston E, Taché Y. Mechanisms and Treatment of Postoperative Ileus. Arch Surg. 2003;138(2):206–214.
6. Georgiadis, G & Markantonis, Sophia & Triantafillidis, John. (2000). Prokinetic agents: Current aspects with focus on cisapride. Annals of Gastroenterology. 13.
7. Reynolds, J.C. & Putman, P.E. (1992) Prokinetic Agents, Gastroenterol Clin of North Am, Vol.21, pp.567-596.
8. Taniyama, K., Makimoto, N., Furuichi, A. et al. Functions of peripheral 5-hydroxytryptamine receptors, especially 5-hydroxytryptamine₄ receptor, in gastrointestinal motility. J Gastroenterol 35, 575–582 (2000).

Introduction

Non-variceal upper gastrointestinal bleeding (NVUGIB) is a common gastroenterological emergency associated with significant morbidity and mortality [1-3]. Upper gastrointestinal endoscopy is currently recommended as the gold standard modality for both diagnosis and treatment [4]. As historically played a limited role in the diagnosis of acute NVUGIB, multidetector-row computed tomography angiography (MDCTA) is emerging as a promising tool in the diagnosis of NVUGIB, especially for severe cases [5-6]. However, to date, evidence concerning the role of MDCTA in the NVUGIB diagnosis is still lacking.

Aims & Methods

The purpose of this study was to retrospectively investigate the diagnostic performance of emergent MDCTA performed prior to any diagnostic modality or following urgent upper endoscopy to identify the status, the site and the underlying etiology of severe NVUGIB. Institutional databases were reviewed in order to identify severe acute NVUGIB patients who were admitted to our bleeding unit and were referred for emergent MDCTA prior to any hemostatic treatment (<3 hours) or following (<3 hours) endoscopy, between December 2019 and October 2022. The study aim was to evaluate the diagnostic performance of MDCTA to detect the status, the site and the etiology of severe NVUGIB with endoscopy, digital subtraction angiography, surgery, pathology or a combination of them as reference standards.

Results

A total of 68 patients (38 men, median age 69 years [range 25–96]) were enrolled. The overall MDCTA sensitivity, specificity, and accuracy to diagnose bleeding status were 77.8% (95% CI: 65.5-87.3), 40% (95% CI: 5.3-85.3), and 75% (95% CI: 63.0-84.7), respectively (Table 1). Finally, the overall MDCTA sensitivity to identify the bleeding site and the bleeding etiology were 92.4% (95% CI: 83.2-97.5) and 79% (95% CI: 66.8-88.3), respectively.

Table 1. The diagnostic performance of MDCTA in detecting bleeding status.

	Active (n = 40)	Recent (n = 26)	Non-active and non-recent (n = 2)	Total (n = 68)
TP	29	20	-	49
TN	-	-	2	2
FP	0	3	-	3
FN	11	3	0	14
Sensitivity (95% CI)	72.5 (56.1-85.4)	87.0 (66.4-97.2)	-	77.8 (65.5-87.3)
Specificity (95% CI)	-	-	100 (15.81-100)	40.0 (5.3-85.3)
PPV (95% CI)	100 (88.1-100)	87.0 (66.4-97.2)	-	94.2 (84.1-98.8)
NPV (95% CI)	-	-	100 (15.81-100)	12.5 (1.55-38.4)
Accuracy (95% CI)	-	-	-	75 (63.0-84.7)

TP, true positive; TN, true negative; FP, false positive; FN, false negative; CI, confidence interval; PPV, positive predictive value; NPV, negative predictive value.

Conclusion

MDCTA seems to be a feasible and effective modality in detecting the site, the status and the etiology of severe acute NVUGIB. It may play a crucial role in the management of selected cases of NVUGIB, especially those clinically severe and/or secondary to rare and extraordinary rare sources, effectively guiding timing and type of treatment. However, further large prospective studies are needed to clarify the role of MDCTA in the diagnostic process of acute NVUGIB.

References

1. Wuerth BA, Rockey DC. Changing Epidemiology of Upper Gastrointestinal Hemorrhage in the Last Decade: A Nationwide Analysis. Dig Dis Sci 2018; 63: 1286–1293.
2. Laine L, Yang H, Chang S-C, et al. Trends for incidence of hospitalization and death due to GI complications in the United States from 2001 to 2009. Am J Gastroenterol 2012; 107: 1190–1195; quiz 1196.
3. Sanders DS, Perry MJ, Jones SGW, et al. Effectiveness of an upper-gastrointestinal haemorrhage unit: a prospective analysis of 900 consecutive cases using the Rockall score as a method of risk standardisation. Eur J Gastroenterol Hepatol 2004; 16: 487–494.
4. Gralnek IM, Stanley AJ, Morris AJ, et al. Endoscopic diagnosis and management of nonvariceal upper gastrointestinal hemorrhage (NVUGIH): European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2021. Endoscopy 2021; 53: 300–332.
5. Napoli A, Fleischmann D, Chan FP, et al. Computed tomography angiography: state-of-the-art imaging using multidetector-row technology. J Comput Assist Tomogr 2004; 28 Suppl 1: S32-45.
6. Wu L-M, Xu J-R, Yin Y, et al. Usefulness of CT angiography in diagnosing acute gastrointestinal bleeding: a meta-analysis. World J Gastroenterol 2010; 16: 3957–3963.

Disclosure

No conflict of interest to declare.

Introduction

Acute severe colitis (ASC) is an important cause of morbidity and mortality in Ulcerative Colitis (UC), requiring hospitalisation and, frequently, colectomy. Intravenous corticosteroids (CS) remain the first-line medical treatment. Approximately 40% of episodes of ASC do not respond to this treatment and require rescue therapy with ciclosporin (CIC) or infliximab (IFX)¹. In the past decades, these treatments and protocol-driven management algorithms led to reduced mortality and colectomy rates. A simple clinical scoring system (the Admission Model for the Intensification of Therapy in Acute Severe Colitis (ADMIT-ASC))³, based on CRP, albumin, and the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score, was recently developed to predict the steroid response on admission.

Aims & Methods

We aimed to retrospectively assess the steroid non-response during admission with ASC and the usefulness of the new prognostic clinical index ADMIT-ASC at admission to predict steroid response in a Belgian tertiary center. All patients admitted with ASC between 1^st January 2015 and 1^st April 2023 were identified from our inflammatory bowel disease database at Erasme University Hospital. Inclusion criteria were ASC patients admitted at the hospital, standard treatment with at least 3 days of intravenous CS and endoscopy evaluation upon admission. ASC was defined according to modified Truelove and Witts’ criteria as ≥6 bloody stools/day with one or more markers of systemic disturbance (tachycardia >90 beats/min, temperature >37.8°C, haemoglobin <105 g/L or CRP >30 mg/L). Steroid non-response was defined as the need for medical rescue therapy (CIC of IFX) or colectomy during the admission. ADMIT-ASC index consists of four points: CRP ≥100 mg/L (1 point), albumin ≤25 g/L (1 point) and UCEIS score ≥4 (1 point) or ≥7 (2 points).

Results

Table I Admission Demographics data (n= 84)	Steroid response (n=49)	Steroid non-response (n=35)	P value
Median disease duration (years) (IQR)	3.6 (0.3-0.9)	2.1 (0.8-5.5)	0.5
Montreal Classification	E1 : 5/49 (10%) E2 : 20/49 (41%) E3 : 24/49 (49%)	E1 : 0/35 E2 : 12/35 (34%) E3 : 23/35 (66%)	0.084
5-ASA, n (%)	22 (45%)	10 (29%)	0.13
Methotrexate or thiopurine, n (%)	6 (12%)	9 (26%)	0.11
Infliximab, n (%)	4 (8.2%)	8 (23%)	0.058
Vedolizumab, n (%)	7 (14%)	5 (14%)	>0.9
Tofacitinib, n (%)	2 (4.1%)	2 (5.7%)	>0.9
Readmission, n (%)	12 (24%)	10 (29%)	0.7
5-ASA, 5-aminosalicylate P values from Wilcoxon rank-sum test or Fisher’s exact test.

Out of 127 patients admitted with UC and treated with intravenous CS during three days, 84 (45% male, median age of 31 years old) were included in the study. Admission demographics and clinical characteristics are described in Table 1.
For 17 patients (20%), the admission was their index presentation of UC. Response to CS was seen in 49 patients (58%). Thirty-three patients (39%) received medical rescue therapy (17/33 IFX and 16/33 CIC). Colectomy rate during admission was 13% after a median duration of 18 days (IQR: 16-54). Admission C reactive protein (CRP) (p=0.036), albumin (p=0.026) and UCEIS scores (p=0.022) were significantly associated with steroid non-response. Patients scoring 0, 1, 2, 3 and 4 had steroid response rates of 90%,75%, 55%, 19% and 0%, respectively. Scoring of ≥3 was 75% (95% CI, 0.43 to 0.95) predictive of steroid failure (OR 5.08, 95%, CI 1.38 to 24.5).

Conclusion

In this tertiary referral cohort study, we confirmed that the ADMIT-ASC index is a simple clinical tool that can be used on the day of admission to predict steroid non-response in ASC with a threshold of ≥3 to identify patients who are unlikely to respond to intravenous CS and enabling timely treatment escalation or surgery.

References

1. Travis S, Satsangi J, Lémann M. Predicting the need for colectomy in severe ulcerativecolitis: a critical appraisal of clinical parameters and currently available biomarkers. Gut 2011;60:3–9.
2. Travis SP, Farrant JM, Ricketts C, et al. Predicting outcome in severe ulcerative colitis.Gut 1996;38:905–10.
3. Adams A, Gupta V, Mohsen W, et al. Gut 2023;72:433–442.

Disclosure

VB has not disclosure.
CDT has not disclosure.
CM has not disclosure.
AC has received lecture fees from Galapagos, Abbvie, Janssen, celltrion, Pfizer, Takeda.
DF has received lecture fees from Abbvie, Astrazeneca, Dr.Falk Pharma, Ferring, Janssen, Mundipharma, MSD, Pfizer, Takeda, Amgen, and advisory board fees from Abbvie, Janssen,Takeda, Celltrion, Amgen.
CL has received consultancy fees from Janssen, Abbvie, Takeda and Galapago and speaker fees from Sandoz, Janssen, Abbvie

Introduction

Gastroscopy is the gold standard for screening for gastric cancer(GC) and precancerous lesions. However, the high miss rate of conventional gastroscopy on detection of early GC and High-grade intraepithelial neoplasia has been reported. In our previous studies, a deep learning-based system (named intelligent and real-time gastroscopy analytical device, IREAD) was proposed and validated, which has shown its great potential for improving early detection of gastric neoplasms.

Aims & Methods

The aim of this study was to evaluate the cost-effectiveness of implementing IREAD-assisted gastroscopy screening for GC. We constructed a decision-analytic Markov model for a cohort of individuals aged 40 years and older for high-risk individuals in China with a total of 40 1-year cycles. We calculated the cost-effectiveness of three screening strategies (non-screening, conventional screening and AI-assisted screening) from a societal perspective (including direct and indirect costs). Screening frequencies and compliance were considered. The sensitivity and specificity of IREAD-assisted and conventional screening were obtained from our previous clinical trials. Prevalence rates, transitional probabilities, costs, and utilities were obtained from published literatures and public data sources. We calculated incremental cost-effectiveness ratios (ICER) using quality-adjusted life-years (QALY). One-way deterministic and simulated probabilistic sensitivity analyses were used to assess the robustness of the main outcomes.

Results

The average cost per patient was $3177,$3530 and $3482 while the average effectiveness was 16.03 QALY,16.04 QALY and 16.05 QALY per individual in non-screening, conventional screening and IREAD-assisted screening, respectively. Compared to the non-screening strategy, the ICERs for conventional screening and IREAD-assisted screening strategy were $20846.66/QALY and $14932.12/QALY, respectively, which were both cost-effective at the predetermined Willingness-to-pay threshold of $25,704/QALY. At the national level, replacement of conventional screening by IREAD-assisted screening could prevent 3372 GC cases and 917 GC deaths per year, and result in a cost savings of $1.75 billion. When setting the screening interval as 2 years according to the current recommendation, we found ICER increased as screening uptake rates decrease. By conducting further comparisons of the screening intervals from 1 to 3 years at 100% uptake, more frequent screening would be associated with a gain of more QALY but with higher costs for both conventional gastroscopy screening and IREAD assisted gastroscopy screening. In all the interval scenarios, the IREAD was cost saving compared to conventional screening and was cost effective compared to non-screening.

Conclusion

The implementation of IREAD-assisted screening was both cost-saving and effective compared to conventional screening. IERAD-assisted screening has potential to further prevent GC incidence and mortality.