The preferred bypass procedure in case of non resectable carcinoma of head of pancreas is-

Surgery for advanced, non-resectable pancreatic adenocarcinoma can palliate obstruction of CBD or duodenum, as well as control visceral pain. Hepaticojejunostomy, choledochojejunostomy or choledochoduodenostomy offers durable drainage of an obstructed bile duct. Cholecystojejunostomy is less reliable but can be employed when tumor bulk precludes common duct procedure. Gastrojejunostomy (antecolic anastomosis) palliates gastric outlet obstruction. Antecolic anastomosis is done to avoid complications from an expanding lesser sac tumor.