Replaced Segment 6 Artery From the Gastroduodenal Artery: A Challenging and Rare Anatomical Variation of Hepatic Artery in Pancreaticoduodenectomy

Variations in the hepatic artery's anatomy can significantly impact planning and executing pancreatic and hepatobiliary surgeries. Of these, the commonest are variations of right and left hepatic arteries originating from superior mesenteric and left gastric arteries, respectively. The anomalous origin of the right hepatic artery from the gastroduodenal artery (GDA) is among the rarest and most challenging anatomy, especially in patients undergoing pancreatoduodenectomy (PD) since GDA ligation is a mandatory step, which may threaten the liver blood supply. We present a 62-year-old male with suspected distal cholangiocarcinoma and plan a robot-assisted pancreatoduodenectomy. Preoperative computed tomography evaluation revealed an anomalous segment 6 artery arising from the GDA and coursing posterolaterally to the common bile duct in the hepatoduodenal ligament. Also, the patient had a replacement left hepatic artery originating from the left gastric artery. The described vascular anomaly has not been previously reported in patients undergoing PD. Awareness of vascular anomalies is the key to performing oncologically radical surgery without increasing bleeding and ischemic complications in patients undergoing complex procedures like PD.