Management of Malignant Gastric Outlet Obstruction Between Surgery and Endoscopy

The aim of this observational study is to compare the outcomes of three different procedures performed for the management of malignant Gastric Outlet Obstruction due to Pancreatic Cancer.

Patients who undergo:

* Surgical gastroenterostomy
* Endoscopic placement of a self-expanding metallic stent
* EUS-guided gastroenterostomy in accordance with standard clinical practice, will be enrolled to evaluate potential differences between the procedures in terms of clinical success, eating experience, chemotherapy tolerance, and nutritional status during follow-up.

Participants will be asked to complete a quality of life questionnaire at baseline and during follow-up; however, no additional procedures will be conducted as a result of participation in the study.

Gastric Outlet Obstruction (GOO) syndrome is a frequent complication of biliopancreatic and gastroduodenal neoplasms and manifests with recurrent vomiting, dehydration and malnutrition, seriously compromising quality of life and the ability to tolerate chemotherapy.

Standard treatment options for GOO are surgical gastroenterostomy (S-GE) or endoscopic placement of a self-expanding metallic stent (ES): surgical treatment achieves better long-term results at the cost of a more invasive procedure. The advances of therapeutic endosonography (EUS) have provided a new possibility to resolve this condition through EUS-guided gastroenterostomy (EUS-GE). The latter involves the creation of a gastroenteric bypass by endoscopically positioning a lumen-apposing metal stent (LAMS). Recent evidence has shown several advantages over previous treatments, in terms of less invasiveness compared to surgery and greater long-term efficacy compared to enteral stenting. However, most of the evidence comes from retrospective protocols and heterogeneous studies that include different neoplasms and clinical courses. Furthermore, the definition of clinical success in the current literature refers to the resolution of the mechanical obstruction of the syndrome, without any in-depth study on the clinical impact of different management strategies in terms of more complex outcomes, such as survival, quality of life, nutritional status and chemotherapy tolerance.

The aim of this study is to prospectively analyze the long-term clinical impact of GOO management strategies in a homogeneous cohort of patients with pancreatic adenocarcinoma (PC) and recent disease diagnosis.

The design of this study is:

* Observational
* Prospective
* Multicentric
* Comparative (3-arms)

No changes to the current clinical practice of the participating centers are foreseen. Each center will candidate the enrolled patient to the procedure that is routinely and currently used in that clinical scenario at their own center. Enrollment in the protocol does not require additional investigations or treatments, except for the administration of quality-of-life questionnaires. Participation in the study implies sharing of information standardly collected during the oncological journey. The prospective follow-up will address clinical efficacy, safety and patient-reported experience, including assessment of the eating experience, chemotherapy tolerance and nutritional status.

Eligibility Criteria:
Inclusion Criteria:

* cyto-/histo-logically confirmed pancreatic cancer
* a maximum of 6 months from pancreatic cancer diagnosis and candidate to active treatment
* stenosis causing gastric outlet obstruction (GOO) due to neoplastic invasion/compression confirmed by radiology or endoscopy extending from the distal one third of the stomach or the duodenum
* patients candidate to either ES or EUS-GE or s-GE

Exclusion Criteria:

* age \< 18 years
* patients with benign or indeterminate gastrointestinal stenosis
* patients with malignant GOO (mGOO) from neoplasia other than pancreatic cancer
* candidates to upfront surgical resection or who already received curative pancreatic resection
* patients who already received a treatment for mGOO
* patients receiving an additional procedure for biliary drainage which might increase the risk of adverse events or hamper the assessment of quality of life; biliary drainage will be allowed if performed uneventfully (without adverse events) at least one day (endoscopic drainage) or one month (surgical hepaticojejunostomy) before mGOO treatment;
* patients carrying any percutaneous drainage (such as percutaneous transhepatic biliary drainage or ascites drainage).
* inability or unwillingness to sign the informed consent form (ICF)
* contraindications to any active palliation of the mGOO, or indication to palliation through venting gastrostomy or nasogastric tube placement alone