Intussusception is more common in children than in adults. In fact, adult intussusception accounts for less than 5% of all cases of intussusception and 1% to 3% of all cases of intestinal obstruction [2]. It affects the small intestine in 48% to 70% of cases, both the ileum and cecum in 25% to 40% of cases, as well as the colon alone in only 5%-8% of cases [5]. Unlike in the child where symptomatic intussusception is almost always idiopathic, in adults symptomatic intussusception is most frequently secondary to an endo-luminal lesion [6].

These lesions are often carcinoma; rarely, it may be benign tumors [3]. Adenomas are the most common colonic benign lesions, while colonic lipomas are less common [1]. They constitute 10% of benign tumors of the digestive tube and 2% to 4% of colon benign tumors. Lipomas can theoretically affect the entire digestive tract, from the hypopharynx to the rectum. In the colon, they are more common in the cecum and ascending colon, and rarer in the left colon. Colonic lipomas primarily affect women aged 50 to 70, are often solitary and submucosal.

They frequently remain asymptomatic and are therefore incidentally discovered during imaging studies, colonoscopies, surgeries, or autopsies. Symptoms, though rare, are more common with pedunculated lipomas larger than 3 cm. These may include abdominal pain, irregular rectal bleeding, anemia, and digestive disorders such as constipation or diarrhea and ultimately leading to an obstructive syndrome. In rare cases, a lipoma can cause acute intussusception [7].

Ultrasonography may be able to diagnose intussusception and lipoma. However, in adults, its performance is limited by the interposition of bowel gas and the corpulence of the patient.

However, it can also show the typical appearance of intestinal intussusception as a "target sign," characterized by two peripheral hypoechoic rings and a central echogenic ring, and in transverse section, as a "sandwich sign," with three superimposed cylinders, which correspond to the intussusceptum and the causative lesion and lipoma is in the form of a regular hyperechogenic lesion surrounded by normal intestinal wall [9]. Abdominal CT is more effective than ultrasound and sensitive and specific for diagnosing intussusception, showing a "bowel within bowel" appearance and associated bowel obstruction. In cases of intussusception caused by lipoma, CT reveals central fat density within the intussusceptum [8].

Regarding histology, a pathological examination is necessary to confirm the diagnosis of lipoma [10,11]. As in our case, analysis of the surgical specimen or biopsies consistently shows the presence of mature adipose cells without any signs of cytonuclear atypia.

 In terms of treatment, in adults, the management of intussusception caused by a lipoma is always surgical and does not allow for reduction by radiological control hyperpressure, due to the frequency of underlying organic causes. A more or less extensive resection may be necessary.