|Home | About | Journals | Submit | Contact Us | Français|
Colonic polyps or carcinomas located within a colonic diverticulum are very rare phenomena. There are a few reports in the literature describing adenocarcinoma arising within colonic diverticulum. Endoscopic resection of the polyp poses a risk of perforation because of the lack of muscular coats in the diverticulum. Therefore, special care should be taken in the treatment of such patients.
There is an increasing number of patients suffering from colonic polyps or diverticular diseases,1–3 mainly due to old age and western type diet.4–7 The treatment of colonic polyps is not complicated; however, colonic polyps within the diverticulum require particular attention in order to avoid perforation because of their thin walls. Therefore, we present this case to remind doctors to take special care when treating polyps or carcinomas located within a colonic diverticulum.
A 42-year-old man, complaining of intermittent bloody stool for 3 months, was admitted for endoscopic polypectomy. Under general anaesthesia and following preparation of the colon with a sodium phosphate solution, the procedure revealed a diverticulum 3 cm in diameter in the sigmoid colon, within which there was a polyp 20 mm long and 25 mm wide, that appeared to have a short and thick peduncle with leukoplakia. After using an endoloop for ligation of the giant polyp with a mixed current (cutting 50 W, coagulating 50 W), we could see peristalsis of the parenteral canal from the perforation which was 10 mm in diameter. Based on the patient’s general stable condition, his age and the very good colonic preparation (fig 1), conservative treatment with several endoclips was promptly undertaken, but failed. An emergency operation was then performed (fig 2). The patient’s postoperative course was uneventful and he was subsequently discharged from hospital. Following histopathological examination of the resected polyp, it was classified as a villous adenoma with low to moderate dysplasia (fig 3).
Colonic polyp and diverticular diseases are common, and their prevalence has increased in recent years.1–3 Both conditions share the same risk factors such as advanced age and western type diet.4–7 As a minimally invasive treatment with minor complications, endoscopic resection is a safe and efficient way to treat colonic polyps, which has been accepted widely. The incidence of perforation during therapeutic colonoscopies has been reported to range from 0.02–2.14%,8,9 depending on the shape of the polyps and the inexperience of the endoscopist. Colonic diverticular disease affects 35% of people over 60 years of age,10 radical treatment for which involving surgical resection has been the usual approach. To the best of our knowledge, this is the first reported case of perforation of a diverticulum in the sigmoid colon following endoscopic polypectomy within the diverticulum. There are nine reports in the literature regarding polyps and carcinomas arising within colonic diverticula.5,11–18 There has also been a report of a case of villous adenoma arising in Meckel’s diverticulum.19 Some of the reports investigated the relation between colonic polyps or carcinomas and diverticula. Some authors argued that the coexistence of diverticular disease and cancer of the large bowel was merely a chance phenomenon,15,16 while others proposed that there was a causal relationship between the two.5
We present a case involving an adenoma arising within the sigmoid diverticulum, with the aim of reminding endoscopists to take special care of such patients. The giant adenoma obstructed the cavity of the diverticulum, and consequently its presence was not detected following an earlier screening colonoscopy in another hospital. Through repeated air insufflation and absorption, the short peduncle with leukoplakia was observed. After using a snare for ligation of the large colonic adenoma, the diverticulum, residue and perforation defect were seen, which were verified by the subsequent surgery. Therefore, we suggest that special care should be taken in such patients, and the endoscopist should observe the polyp carefully through repeated air insufflation and absorption. If a polyp is discovered within the diverticulum, especially if it is large, a laparoscopic enterectomy would be preferable, as endoscopic resection of the polyp could involve the risk of perforation because of the lack of muscular coats in the diverticulum.
Competing interests: None.
Patient consent: Patient/guardian consent was obtained for publication.