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Colon interposition for oesophageal replacement.

The choice of the colon as an oesophageal substitute results primarily from the unavailability of the stomach. However, given its durability and function, colon interposition keeps elective indications in patients with benign or malignant oesophageal disease who are potential candidates for long survival. The choice of the colonic portion used for oesophageal reconstruction depends on the required length of the graft, and the encountered colonic vascular anatomy, the last being characterised by the near-invariability of the left colonic vessels, in contrast to the vascular pattern of the right side of the colon. Accordingly, the transverse colon with all or part of the ascending colon is the substitute of choice, positioned in the isoperistaltic direction, and supplied either from the left colic vessels for long grafts or middle colic vessels for shorter grafts. Technical key points are: full mobilisation of the entire colon, identification of the main colonic vessels and collaterals, and a prolonged clamping test to ensure the permeability of the chosen nourishing pedicle. Transposition through the posterior mediastinum in the oesophageal bed is the shortest one and thereby offers the best functional results. When the oesophageal bed is not available, the retrosternal route is the preferred alternative option. The food bolus travelling mainly by gravity makes straightness of the conduit of paramount importance. The proximal anastomosis is a single-layer hand-fashioned end-to-end anastomosis to prevent narrowing. When the stomach is available, the distal anastomosis is best performed at the posterior part of the antrum for the reasons of pedicle positioning and reflux prevention, and a gastric drainage procedure is added when the oesophagus and vagus nerves have been removed. In the other cases, a Roux-en-Y jejunal loop is preferable to prevent bile reflux into the colon. Additional procedures include re-establishment of the colonic continuity, a careful closure of the mesentery to avoid a further internal hernia, and routine appendectomy. When applying these technical aids, the chances of achieving a viable and well-functioning colon graft are excellent.