Post hoc validation of a tool that accurately predicts the outcome of endoscopic therapy in Bouveret syndrome

Abstract

Background Bouveret syndrome is characterized by gallstone impaction in the upper gastrointestinal tract causing gastric outlet obstruction. In Bouveret syndrome, endoscopic gallstone removal can avert the need for surgery. However, in cases in which endoscopic therapy is unlikely to succeed, endoscopic attempts delay definitive treatment and compound patient risks. We previously developed a model that predicts endoscopic outcomes from data derived through a systematic review. This tool uses gallstone length, site of impaction, and the number of planned methods of lithotripsy to predict the likelihood of endoscopic success with an accuracy of 81.0%. This study aimed to evaluate our tool performance in an independent, non-training data set and assess endoscopic and surgical outcomes. Methods Systematic searches of the PubMed, Scopus, and Cochrane databases were performed for articles published between 16 April 2018 and 1 June 2021. The data reported after our previous study were harvested and inputted into the tool to evaluate their ability to accurately predict outcomes when compared with actual outcomes. Results Newly collated data in fields of interest showed no significant statistical differences compared with previous training data sets. Endoscopic therapy was successful in 41.9% of cases. Gallstones of ≤4 cm had a higher chance of successful endoscopic intervention (odds ratio 6.7, 95% confidence interval 1.7–25.8, P < 0.01). Complications of surgery were reported in 29.5%; there was one fatality reported. Post hoc evaluation of our predictive tool demonstrated an AUROC score of 0.80. Conclusions We have demonstrated in an independent data set that the tool can be used to accurately predict outcomes of endoscopic therapy. Patients in whom endoscopic therapy is most likely to fail should be offered an early surgical opinion.

Multiple Cholecystoenteric Fistulae With Bouveret Syndrome and Acute Pancreatitis: A Rare Combination

“…Since then, the success rate for endoscopy has gradually improved to almost 40% using snare, net, basket, and lithotripsy (mechanical and laser) [20][21][22]. It has reduced treatment-associated morbidity and mortality too [22].…”

“…Since then, the success rate for endoscopy has gradually improved to almost 40% using snare, net, basket, and lithotripsy (mechanical and laser) [20][21][22]. It has reduced treatment-associated morbidity and mortality too [22]. A tool devised by Ong et al based on stone length, location of stone impaction in duodenum, and number of endoscopic modalities to be used to predict the outcome of endoscopy showed excellent correlation [21].…”

“…A tool devised by Ong et al based on stone length, location of stone impaction in duodenum, and number of endoscopic modalities to be used to predict the outcome of endoscopy showed excellent correlation [21]. Post hoc analysis by Swift et al confirmed that the aforementioned tool can be used successfully to predict endoscopy outcomes in BS [22]. According to their analysis, stone ≤ 4 cm and in the proximal duodenum (first part) has higher success with endotherapy.…”

“…According to their analysis, stone ≤ 4 cm and in the proximal duodenum (first part) has higher success with endotherapy. For larger stones and those located in difficult locations, second-line surgery is needed in >60% of cases [22]. We avoided endoscopy for the same reason (stone size).…”

“…Meticulous dissection, skills in intracorporeal suturing, and staplers ensure safe and successful surgery [3,6]. The success of MIS for BS is gradually improving though numbers are small [22]. The rarity of the problem, an increasing number of successful endoscopies [22], conversion to laparotomy due to adhesions, bleeding, difficult intracorporal closure [6], direct laparotomy due to simultaneous Mirizzi Syndrome [24], or insufficient laparoscopy experience may be responsible for smaller numbers.…”