CHOLECYSTOSCOPY AND LAMS REMOVAL IS ASSOCIATED WITH HIGHER STONE-RELATED COMPLICATIONS AS COMPARED TO LONG TERM LAMS IN SURGICALLY UNFIT PATIENTS WITH EUS-GBD PERFORMED FOR ACUTE CALCULOUS CHOLECYSTITIS

Introduction
EUS-GBD with lumen apposing stent (LAMS) has been included in ESGE and ASGE guidelines for acute calculous cholecystitis for patients who are unfit for surgery. Whether to perform cholecystoscopy for stone removal and LAMS removal, or the LAMS should be kept for long term is still a controversy. The aim of this study is to compare the outcomes of each group.

Methods
This was a retrospective study including all surgically unfit patients who suffered from acute calculous cholecystitis with EUS-GBD performed from Dec 2013 to Jun 2023 in Prince of Wales Hospital (PWH), Hong Kong and Hospital Universitario Rio Hortega (HURH), Spain. The protocol of PWH is to repeat cholecystoscopy until stones cleared and LAMS removal (Group A). The protocol of HURH is for long term LAMS (Group B). The primary outcome was recurrent biliary events (including cholecystitis, cholangitis, biliary pancreatitis). Secondary outcomes include demographics, previous ERCP and sphincterotomy, early and late complications, hospital stay, emergency room visits, readmissions and follow-up time.

Results
65 patients from PWH (Group A) and 96 patients from HURH (Group B) were recruited. 19 patients from PWH crossovered to Group B while 8 patients from HURH crossovered to Group A. As a result, there were 54 patients in Group A and 107 patients in Group B. 20/54 (37.0%) in Group A and 14/107 (13.1%) in Group B suffered from recurrent biliary event during follow-up (adjusted for previous ERCP and sphincterotomy with logistics regression; p<0.001). Figure 1 shows the Kaplan Meir curve. There was no difference between early complications (<30d) and stent-related complications. However, there were more late complications from Group A (22/54 (40.7%) vs 8/107 (7.5%); p <0.001). The no. of emergency visits (5.2 (6.8) vs 2.2 (2.4); p =0.001) and stone-related readmissions (0.7 (1.1) vs 0.2 (0.47); p <0.001) were significantly more in Group A. In Group A, 1.17 (0.6) cholecystoscopies were required to clear all the stones. 22/54 (40.7%) patients in Group A had recurrent gallstones on imaging. The mean follow-up time was 42.2 (30.0) days and 26.2 (23.3) days for Group A and B respectively (p<0.001). Table 1 showed the details of the outcomes.

Conclusion
Cholecystoscopy for stone removal and subsequent LAMS removal was associated with significantly more recurrent biliary events after EUS-GBD when compared to long term LAMS while thhere was no increase in stent-related complications in the long term LAMS group. Long term LAMS may be a better alternative after EUS-GBD for surgically unfit patients suffering from acute calculous cholecystitis.