Robot-assisted right hemicolectomy for ascending colon cancer with a rare common trunk for the ileocolic and middle colic arteries: a case report.

Introduction: Anatomical variations in the arterial supply to the right colon are clinically relevant in patients undergoing laparoscopic and robotic colectomy, as misidentification of the vessels may lead to inadequate lymphadenectomy or bowel ischemia. A common trunk formed by the ileocolic artery (ICA) and middle colic artery (MCA), arising from the superior mesenteric artery (SMA), is an uncommon vascular configuration that may complicate surgical decision-making. Presentation of case: A 73-year-old man presented with constipation and abdominal pain. Colonoscopy revealed a circumferential type 2 tumor in the ascending colon, causing luminal stenosis. Histopathological examination of a biopsy confirmed moderately differentiated adenocarcinoma. Using contrast-enhanced computed tomography, wall thickening without distant metastasis was detected. Three-dimensional computed tomography angiography revealed a rare vascular anomaly in which the ICA and MCA originated from a common trunk arising from the SMA, accompanied by the absence of the right colic artery. The patient underwent an elective robot-assisted right hemicolectomy using the da Vinci Si® system. The postoperative course was uneventful; the patient was discharged on postoperative day 8. The pathological diagnosis was pT3N0M0, stage IIa adenocarcinoma. No recurrence has been observed during the 3-year follow-up. Discussion: Preoperative three-dimensional vascular imaging is useful for identifying uncommon vascular variants and translating findings into a safe intraoperative strategy. The robotic approach allows precise vascular handling in such cases. Conclusions: Awareness of such anatomical configurations may help prevent intraoperative misinterpretation and support meticulous preoperative planning, particularly in minimally invasive and robotic right colectomy.