Study on sufficient blood vessel ligation and bowel mobilization in laparoscopic surgery for ascending colon cancer

Although well established, laparoscopic surgery for ascending colon cancer is a difficult procedure due to the presence of many blood vessels requiring treatment and the need for sufficient mobilization to extract the right colon through a small laparotomy. This is the first study to investigate the adequacy of vascular ligation and bowel mobilization for laparoscopic resection of ascending colon cancer and extracorporeal reconstruction. This retrospective study included 103 consecutive patients who underwent laparoscopic colectomy for ascending colon cancer from 2015 to 2022 at the Center Hospital of the National Center for Global Health and Medicine. We analyzed correlations between clinicopathological factors and vessels ligation or the mobilization range. The strongest factor correlated with vascular ligation was the distance from the Bauhin valve to the distal edge of the tumor (Length B). These lengths were significantly longer in the vascular ligated group (the right colic artery (RCA): 81 mm; the accessory right colic vein (ARCV): 85 mm; right branch of the middle colic artery (MCA-rt): 106.5 mm) than in the nonligated group (50 mm, 43 mm, 50 mm, p < 0.01). Mobilization range was not correlated with tumor location or size. According to the result, we developed practical indicators to assist during laparoscopic surgery: i) To omit the RCA ligation, Length B should be shorter than approximately 5 cm; ii) If Length B exceeds approximately 8 cm, both the RCA and ARCV should be ligated; and iii) If Length B exceeds approximately 10 cm, the MCA-rt should be ligated.