Laparoscopic management of sigmoid colon intussusception caused by a malignant tumor: case report.

Palabras clave: Laparoscopia. Intususcepción. Cáncer de colon. Adult intussusception is a relatively rare condition. It accounts for 1% of patients with bowel obstruction and 5-10% of all intussusceptions. We describe a case of adult intussuscep-tion of the sigmoid colon caused by malignancy which was successfully treated by laparoscopic resection. A 56-year-old man was admitted to our hospital with the chief complaint of bloody stools and tenesmus for 3 days. The patient was well before this admission. Digital rectal examination revealed a mass in the rectum about 7 cm proximal to the anal verge with fixation and irregular surface. All laboratory tests, including the tumor markers, were within normal limits. Colonoscopy revealed a huge fungating tumor located at 12 cm from anal verge leading to nearly completely obstruct the lu-men. Ultrasound demonstrated a target lesion over the sigmoid colon area with concentric rings of alternating hypoechoic and hyperechoic layers with echogenic center and the " pseudokid-ney sign " on the longitudinal view (Fig. 1). Coronal magnetic resonance image (MRI) of abdomen displayed an intussuscep-tion mainly from the proximal sigmoid colon invaginated into the rectum with total length about 16 cm (Fig. 2). Sigmoidorectal intussusception due to a sigmoid colon tumor was impressed. Surgical treatment was suggested, and the patient requested laparoscopic resection. At laparoscopy, the sigmoid colon was found to be intussuscepted into the rectum. Mobilization and reduction of the sigmoid colon was performed intracorpore-ally, and the mesentery was divided using Harmonic scalpel and endoclips. Reanastomosis of colon and rectum was then carried out after resection of the sigmoid colon tumor which was 40 cm far from the anal verge. The patient's postoperative course was uneventful, and the cosmetic result was excellent. The patient was discharged 8 days after surgery on a diet as tolerated and returned to all activities of daily living 1 week later. Organic lesions usually result in adult intussusception whereas most pediatric intussusception is idiopathic. A 63-87% of colonic intussusceptions in adults are caused by malignant tumors and 29-33% by benign tumors (1). Most of the benign etiologies are lipoma and adenoma (2). In a review of 32 adults with colonic intussusception due to malignant tumors reported in Japan over a 10-year period, 14 cases were located in the sig-moid colon. There are many tools to diagnose colonic intussusception. The characteristic appearance of barium enema is " a cup-shaped filling defect " or " a spiral or …