Global Gastrointestinal Stent Market Assessment, By Product [Biliary Stents, Duodenal Stents, Colonic Stents, Pancreatic Stents, Esophageal Stents], By Material [Self–Expanding Metal Stents, Plastic Stents], By Application [Biliary Diseases, Irritable Bowel Syndrome, Gastrointestinal Cancers, Colorectal Cancer, Stomach Cancer, Esophageal Cancer, Pancreatic Cancer], By End-user [Hospitals and Clinics, Ambulatory Surgical Centers], By Region, Opportunities and Forecast, 2017-2031F