Esophago-Gastric Cancer after One Anastomosis Gastric Bypass (OAGB)

One Anastomosis Gastric Bypass (OAGB) is a bariatric technique that combines a long tube-like gastric conduit with a wide end-to-side gastro-jejunostomy. It is a non-complex operation with a low frequency of intestinal obstructions and an excellent long-term weight loss, however, there is a fear of esophagogastric cancer. This narrative review explores the risk of cancer development after OAGB. Five gastric cancers were published after loop gastric bypass (an early version of OAGB, n=4) and after modern OAGB (n=1), four of which occurred in the remnant stomach and one in the gastric stump. Jejuno-gastric reflux is normal after OAGB, but there is little or no evidence to suggest bile-induced malignant degeneration in the stomach. On the contrary, gastro-esophageal reflux is a clear cause of metaplasia and AEG, although gastro-esophageal reflux is rare after OAGB with only two cases of AEG in the literature. Postoperative gastroscopic surveillance should be considered in patients with gastro-esophageal reflux and/or hiatal hernia. When reflux becomes symptomatic, diversion of the OAGB into a Roux-en-Y construction should be recommended.