Large prospective comparative observational study in numerous reference centers in France, comparing infectious complications in patients admitted for pancreatic cystic lesions (PCL) aspiration performed with or without antibiotic prophylaxis (ATBp) according to the usual practices.

This is a prospective, comparative, observational, multicenter study, with the primary objective of comparing the infection rates in pancreatic cystic lesions (PCL) aspirated under EUS, with and without the administration of ATBp.

A sample size of 1702 patients will be needed over a 3-year study period.

The complication rate after EUS fine needle aspiration (EUS-FNA) for pancreatic cystic lesions (PCL) is low, around 1-3% according to various series. However, it has long been recommended to perform this procedure under antibiotic prophylaxis (ATBp). Due to the risk of developing resistance to certain classes of antibiotics and the risk of complications, particularly allergic reactions, the role of ATBp in this indication needs to be reconsidered. The latest recommendations from European and French societies do not support the systematic formal indication of ATBp for aspiration under EUS. Because the literature on the subject is sparse and equivocal, practices remain varied (some performing PCL aspirations with and others without ATBp), and scientific societies do not provide a formal stance on the benefit of such ATBp. Therefore, we decided to conduct a very large prospective comparative observational study in numerous reference centers in France (centers of the Research and Action Group in Endoscopy - GRAPHE), comparing infectious complications in patients admitted for EUS-FNA for PCL performed with or without ATBp according to the usual practices .

This is a prospective, comparative, observational, multicenter study.

Primary objective:

Comparison of infection rates after EUS-FNA for pancreatic cystic lesions (PCL) , with and without the administration of ATBp.

Secondary objectives:

Rates of other infectious complications (pulmonary, urinary, etc.) Rates of post-ATBp complications, particularly allergic reactions Prolongation of scheduled hospitalization Evaluation of factors associated with post-EUS aspiration infection of PCL

After the endoscopic exploration, the patient will be monitored for the potential occurrence of complications related to EUS (perforation, hemorrhage, infection, allergy, etc.). Any adverse events will be recorded at 30 days post-procedure.

A sample size of 1702 patients will be needed over a 3-year study period.

Inclusion Criteria:

• Patient referred for diagnostic aspiration of a pancreatic cystic lesion
• Patient aged 18 years or older
• Patient with ASA 1, ASA 2, ASA 3 status
• No participation in another concurrent clinical study

Exclusion Criteria:

• Patient under 18 years old
• Patient with ASA 4 or ASA 5 status
• Pregnant woman
• Patient with coagulation disorders preventing the performance of an EUS-FNA: PT < 50%, platelets < 50,000/mm³, current effective anticoagulation, ongoing clopidogrel, prasugrel, or ticagrelor treatment
• Patient unable to personally express non-opposition or legally protected adult

Patients with pancreatic cystic lesions for whom an EUS-FNA is indicated