Recurrent intussusception of the sigmoid colon caused by a transanal protruding sessile tubulo-villous malignant polyp

We report a case of a 35 year-old woman with a large malignant sessile tubu lo-villous polyp of the proximal end of a dolico-sigmoid colon causing intu ssusception and transanal prolapsing. The diagnosis presented some difficul ties being the intussusception intermittent. The clinical feature had been initially misdiagnosed for a very large bleeding polyp (5 cm in size), prot ruding out of the anus with a long pedicle in the rectum. The histology of multiple bioptic samples of the lesion revealed malignancy. Conventional ra diologic studies (plain x-rays, barium enema) after metal clips had been pl aced on the head of the polyp before it rose up the colon, led to the corre ct diagnosis without, nevertheless, documenting intussusception. An electiv e surgical resection of the dolico-sigmoid colon allowed the correct diagno sis and the curative treatment of the colonic intussusception and the malig nancy.