we report a case of adult intussusception caused by a submucosal lipoma in the sigmoid colon , review the literature and discuss the optimal management . a 44-year - old woman visited our emergency room with sudden onset of intermittent abdominal cramps . 1 ) . since the clinical presentation was that of an imminent ileus a laparotomy was performed . 4 ) , and en - bloc resection was performed with end - to - end anastomosis . the postoperative course was uneventful and the patient was discharged on day six postoperative . the pathology report revealed a 6 cm submucosal lipoma of the sigmoid with reactive changes ( fig . is associated with an identifiable etiology in 90% of cases , the so - called leading point . consequently , non - operative reduction is not the treatment of choice in adults as it is in children . this reflects the greater prevalence of malignant tumors ( adenocarcinoma and lymphoma ) in the colon compared with the small bowel . benign lesions constitute about 30% and include neoplasms such as lipoma , adenomatous polyp , neurofibroma , hemagioma and leiomyoma . postoperative causes might consist of adhesions , motility disorders , presence of suture materials or an anastomosis . idiopathic intussusception occurs less often than in the small bowel and is a rare entity . although lipoma represents the most common benign tumor of the colon , it is a relatively rare cause of gastrointestinal symptoms . postmortem series have shown that up to 4% of gastrointestinal tumors are lipomas . in the majority of the patients preferential location is the right sided hemi colon , accounting for nearly 90% of cases [ 3 , 4 ] . most of the time the lipoma is situated submucosally , but it can also be subserosal , originating from an appendix epiploica . large lipomas are usually symptomatic and may mimic clinical signs almost identical to malignant tumors . symptoms are often chronic , with intermittent abdominal pain being the main symptom . unlike intussusception in children , intussusception is often not considered clinically in the differential diagnosis of adult patients with vague abdominal complaints . with the widespread use of ct and increasing numbers of colonoscopies in the evaluation of non - specific abdominal pain , while the appearance of intussusception is characteristic on ct , its etiology usually can not be established . on ct a lipoma has a uniform appearance with fat - equivalent density and a smooth border . however , even if the radiological image may suggest strong evidence for the existence of a lipoma , radiologists will often also mention other more malignant options in their differential diagnosis . colonoscopy may show some characteristic findings in patients with a submucosal lipoma : a yellow submucosal mass with marked elasticity , easily demonstrated by compressing and releasing the tissue with a closed biopsy forceps . furthermore , fat tissue may protrude through the biopsy site , this is called the naked fat sign [ 5 , 6 ] . nevertheless , the colonoscopic image may be deceptive , presenting with hemorrhage , necrosis and mucosal ulceration . small lipomas ( < 2 cm ) can be safely removed endoscopically [ 8 , 9 ] . the risk of perforation or hemorrhage is increased because the fatty tissue is an inefficient conductor for electronic current , especially when the lesion is sessile . en - bloc resection of the effected intestine should be the surgical treatment of choice in the majority of cases due to the high percentage of malignancy . if the preoperative diagnosis of colon lipoma can be made correctly , extent of surgery may be appropriately limited . the most important factor for establishing the diagnosis of intussusception caused by a submucosal lipoma is awareness of the possibility , especially in adult patients with abdominal symptoms and prior episodes of partial intestinal obstruction . submucosal lipomas are usually asymptomatic but may cause bleeding , obstruction , intussusception , or abdominal pain .
adult intussusception is a rare clinical presentation and often not considered clinically in the differential diagnosis of adult patients with vague abdominal complaints . 
 a 44-year - old woman visited our emergency department with sudden onset of intermittent abdominal pain . 
 diagnostic imaging revealed an intussusception caused by a submucosal lipoma of the sigmoid . 
 a laparotomy was performed and the diagnosis was proven by histological examination . 
 submucosal lipomas are usually asymptomatic but may cause bleeding , obstruction , intussusception , or abdominal pain and thus mimic a malignancy . 
 surgical excision is indicated for symptomatic cases .