Two cases of strangulated bowel obstruction due to exposed vessel and nerve after laparoscopic and robot-assisted lateral lymph node dissection (LLND) for rectal cancer.

BACKGROUND: The majority of small bowel obstructions (SBO) are caused by adhesion due to abdominal surgery. Internal hernias, a very rare cause of SBO, can arise from exposed blood vessels and nerves during pelvic lymphadenectomy (PL). In this report, we present two cases of SBO following laparoscopic and robot-assisted lateral lymph node dissection (LLND) for rectal cancer, one case each, of which obstructions were attributed to the exposure of blood vessels and nerves during the procedures.

CASE PRESENTATION: Case 1: A 68-year-old man underwent laparoscopic perineal rectal amputation and LLND for rectal cancer. Four years and three months after surgery, he visited to the emergency room with a chief complaint of left groin pain. Computed tomography (CT) revealed a closed-loop in the left pelvic cavity. We performed an open surgery to find that the small intestine was fitted into the gap between the left obturator nerve and the left pelvic wall, which was exposed by LLND. The intestine was not resected because coloration and peristalsis of the intestine improved after the hernia was released. The obturator nerve was preserved. Case 2: A 57-year-old man underwent a robot-assisted rectal amputation with LLND for rectal cancer. Eight months after surgery, he presented to the emergency room with a complaint of abdominal pain. CT revealed a closed-loop in the right pelvic cavity, and he underwent a laparoscopic surgery with a diagnosis of strangulated SBO. The small intestine was strangulated by an internal hernia caused by the right umbilical arterial cord, which was exposed by LLND. The incarcerated small intestine was released from the gap between the umbilical arterial cord and the pelvic wall. No bowel resection was performed. The umbilical arterial cord causing the internal hernia was resected.

CONCLUSION: Although strangulated SBO due to an exposed intestinal cord after PL has been a rare condition to date, it is crucial for surgeons to keep this condition in mind.