Randomized Trial of Percutaneous vs. Endoscopic Gallbladder Drainage

Percutaneous or Endoscopic Gallbladder Drainage: The PEG Trial

This is a randomized trial of patients with acute calculous cholecystitis who are never-surgery candidates. Patients will be randomized to one of two treatment groups, percutaneous cholecystostomy or endoscopic ultrasound-guided drainage. The aim of the study is to compare between these two treatment methods, the treatment outcomes and quality of life over a follow-up duration of 36 months.

Acute calculous cholecystitis (ACC) is characterized by an inflammatory condition involving the gallbladder wall, most often caused by an obstruction at the infundibulum or cystic duct, with less than 10% of cases provoked by other causes.

Surgical cholecystectomy (SC), especially by laparoscopic assistance, is considered the gold standard approach for the treatment of ACC. However, some patients due to high frailty, multiple comorbidities, and clinically significant organ failure are considered suboptimal or "unfit" candidates for surgery. Therefore, less invasive approaches have been developed for this challenging population.

Percutaneous choleystostomy (PC) has been traditionally considered the first alternative in patients who are not considered for surgery, as it is a less invasive approach with lower rates of complications compared to SC. The procedure is considered technically easy for experienced interventional radiologists and is based on the insertion of a percutaneous catheter in the gallbladder under fluoroscopic assistance after an ultrasound-guided puncture with an 18-gauge needle. Nevertheless, like any other procedure, PC is not exempt from complications, such as bleeding, pneumothorax, peritonitis, injury to adjacent organs, pain at the site of insertion, catheter dislodgement, and risk for recurrent cholecystitis upon removal of the catheter.

Endoscopic ultrasound (EUS)-guided gallbladder drainage (EUS-GBD) has been described as another minimally invasive option for these patients. Under endoscopic ultrasound-guidance, a lumen-apposing metal stent is placed within the gallbladder lumen from the stomach or the duodenum (EUS-GBD), thus allowing internal drainage. EUS-GBD appears to have some benefits over PC, since the latter is typically associated with patient's discomfort and pain at the site of insertion, and carries inherent disadvantages associated with external drainage.

The management of ACC in patients who are not surgical candidates is complex. These patients carry a high risk of peri-cholecystectomy and post-cholecystectomy complications and a mortality rate of up to 19%. The initial management of patients who are not surgical candidates consists of antibiotic therapy and minimally invasive procedures for adequate gallbladder drainage. These procedures include PC and endoscopy-guided gallbladder drainage. Tokyo Guidelines-2018 (TG-18) recommend PC as the standard drainage method for surgically high-risk patients with AC. World Society of Emergency Surgery 2020 guidelines recommend considering endoscopic transpapillary gallbladder drainage (ET-GBD) or EUS-GBD as an alternative to PC in high-volume centers when performed by skilled endoscopists. There is a lumen-apposing metal stent (LAMS), which was recently approved by the Food and Drug Administration (FDA) for EUS-GBD in poor surgical candidates.

In a prior study (DRAC 1) that compared PC versus EUS-GBD in high-risk patients with ACC, EUS-GBD was associated with significantly fewer adverse events, readmissions and recurrent cholecystitis. However, the follow-up duration was only 12 months, which is a very short timeframe to reliably compare long-term outcomes between modalities. This is particularly relevant as nearly 45% of patients who do not receive a cholecystectomy die within 825 days of an attack of ACC. Also, health-related quality of life and treatment costs were not assessed in DRAC 1. Finally, the primary outcome in the DRAC 1 trial was only a single measure - adverse events. The burden of ACC and the impact of treatment is more accurately measured using a composite endpoint encompassing readmissions and reinterventions in addition to adverse events.

We hypothesize that by performing EUS-GBD as the first-line therapy in never-surgery patients presenting with ACC, the rates of procedural reinterventions, readmissions, and disease or procedure-related adverse events can be reduced as compared to patents undergoing percutaneous cholecystostomy.

Inclusion Criteria:

• Patients with suspected or confirmed acute calculous cholecystitis, diagnosed per Tokyo guidelines
• Age ≥ 18 years
• Patients due to severe comorbidity who are deemed to be never-surgery candidates by the multidisciplinary team or patients who refuse to undergo surgery.
• Patients can undergo EUS-guided drainage and percutaneous cholecystostomy tube placement.
• Written informed consent by the patient or guardian who can understand the nature and possible consequences of participation in the study.

Exclusion Criteria:

• Pregnancy
• Patients who are potential candidates for future cholecystectomy.
• Patients unwilling to undergo follow-up assessments.
• Patients with suspected gangrene or perforation of the gallbladder
• Patients are diagnosed with concomitant liver abscess or necrotizing pancreatitis.
• Altered anatomy of the upper gastrointestinal tract due to surgery of the esophagus, stomach and duodenum.
• Indwelling percutaneous cholecystostomy tube.
• Refractory/persistently significant ascites despite paracentesis.
• Distance between the gallbladder and gastric/duodenal wall that cannot be bridged by the metal stent.
• Abnormal coagulation parameters that cannot be correct: INR > 1.7 and/or platelets < 50.000/mm3