|Ahead of print publication
Unusual case of lipoma sigmoid colon
Shivam Sharma, Subhash Chawla, Naveen Yadav, Sangeet Manchanda
Department of Minimal Access Surgery, MMIMSR, Ambala, Haryana, India
|Date of Submission||18-Mar-2020|
|Date of Decision||15-May-2020|
|Date of Acceptance||14-Sep-2020|
Department of Minimally Access Surgery, MMIMSR, Ambala - 133 207, Haryana
Source of Support: None, Conflict of Interest: None
Colonic lipomas are nonepithelial tumors usually detected incidentally during abdominal surgery or colonoscopy. Lipomas generally remain asymptomatic, when they exceed 2 cm of diameter they may cause abdominal pain, obstruction, or intussusception. Here, we present a case of an elderly woman referred by her general practitioner to minimally access surgery outpatient department presented with complaints of passing loose stools 7–8 times a day. Triphasic computed tomography scan confirmed the diagnosis. To reduce the risk of malignancy, laparoscopic-assisted excision of lipoma was done. Histopathological examination of the specimen confirmed the diagnosis of lipoma sigmoid colon.
Keywords: Colonoscopy, intestinal lipoma, sigmoid lipoma, triphasic computed tomography
| Introduction|| |
Colonic lipomas are rare benign tumors and are usually asymptomatic. Large lesions cause symptoms such as abdominal pain, constipation, diarrhea, and obstruction mostly due to intussusception. The epidemiological, macroscopic, and clinical presentation can sometimes suggest a malignant nature, although malignant transformation does not occur. We present a rare case of large broad-based intraluminal lipoma of the sigmoid colon in a middle-aged female patient who presented with symptoms of enteritis.
| Case Report|| |
A 47-year female presented to medicine outpatient department with a history of increased frequency of stools for the past 3 months. Stools were watery in consistency, nonsticky, non foul-smelling, and frequency 8–9 times a day. This was not associated with fever, abdominal pain, abdominal distension, vomiting, loss of appetite, or weight. The patient had a medical history of hypothyroidism for 6 months and was on oral Thyroxine 50 mcg per day. There was no significant past history suggestive of subacute intestinal obstruction. Per abdomen soft, nontender, and no palpable lump. The digital rectal examination did not reveal any mass or blood on the finger cot.
Laboratory investigations including complete blood count (HB-10.0 g%, packed cell volume 34.3%, total leukocyte counts 6.7 × 1000/cu/mm), liver function tests (total protein 6.9 g/%, Direct Bilirubin 0.79 mg/dl, SGOT 27u/l, SGPT 22u/l, alkaline phosphatase 77u/l, albumin 3.6 g/%, and viral markers (Non Reactive) internationalized normalized ratio 1.45, bleeding time/clotting time 6.30/2.15, serum eletrolytes NA + 138 meq/l, K+ 4.3 meq/l, chloride 104 meq/l, C-reactive protein 0.9 mg/L, and erythrocyte sedimentation rate 07 mm at 1st h.
Colonoscopy revealed intraluminal mass lesion of approximately 4 cm × 2 cm spherical, smooth surface with no ulceration in the proximal part of sigmoid colon? submucosal. Colonoscopic-guided biopsy revealed only inflammatory tissue [Figure 1].
|Figure 1: Triphasic computed tomography of the abdomen shows mass in the sigmoid colon|
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Triphasic computed tomography (CT) scan showed redundant and tortuous sigmoid colon with a large well-defined lesion of size 4.6 cm × 2.8 cm in the sigmoid colon with absorption densities of–110 Hounsfield units, typical of fat suggestive of lipoma causing significant occlusion of the lumen [Figure 2].
|Figure 2: Colonoscopy shows smooth globular mass 40 cm from anal vergein sigmoid colon|
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The patient was planned for diagnostic laparoscopy and proceed, intraoperative finding showed a swelling in the proximal part of sigmoid colon, lipoma could be seen extruding out of serosal layer such as the tip of the iceberg, as CT findings were highly suggestive of lipoma, so laparoscopic-assisted excision of lipoma was done by giving transverse skin incision approximately 5 cm in the left iliac fossa and sigmoid colon was pulled out and longitudinal incision was given over the swelling and lipoma present between submucosa and muscular layer was dissected out and primary closure of the incision was done in two layers [Figure 3] and [Figure 4].
|Figure 3: Intraoperative: Lipoma peeping from the serosal surface such as the tip of the iceberg|
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Postoperative period was uneventful, the patient was kept nil orally for 2 days then started with oral liquids followed by semisolid diet on the 3rd postoperative day, the patient tolerated orally well and passed stools on the 4th postoperative day and was discharged.
| Discussion|| |
Lipoma of the colon is the second-most common benign tumor found rarely. The first case was reported by Bauer in 1757 and only 300 cases have been reported till now. According to recent studies by Rogy et al. states that lipoma of the colon constitutes about 0.3% of cases includes colorectal problems and 1.8% of cases of benign colorectal disease. More than 75% of lesions are found in the right colon and 10% are multiple mostly in the region of the cecum. Submucosal lipomas are found in 90% of colonic lipomas, the rest found in serosal or intramucosal layers. Incidence is more in females as compared to males and in male patients is more often seen on the left side. In our case on the contrary patient is female and lipoma is seen on the left side.
Lipomas of the colon are asymptomatic found incidentally during radiological imaging or following colonic surgery for other conditions. It is observed that size >4 cm causes symptoms and it depends on location too. Symptoms such as pain in the abdomen, change in bowel habits, bleeding per rectum, and features of obstruction. Complications include perforation, intussusception, prolapse, and in some cases massive hemorrhage. Larger size can cause surface ulceration and bleeding.
Contrast studies such as barium enema, triple-phase CT scan (in this case), or magnetic resonance imaging imaging helps in diagnosis. CT has been reported to be the most useful tool for the detection of these lesions., In general, they are seen as spherical orovoid masses with absorption densities of–40 to –120 Hounsfield units, typical of fat. CT appearance may be atypical if fat necrosis or infarction is present. For large colonic lipomas and acutely ill patients. Despite the diagnostic tools, differentiation from malignant processes is the main challenge before surgical resection. If the size of lipoma is <2 cm then it is difficult to identify on radiological investigations and complications such as intussusception or bowel wall thickening may be misdiagnosed as malignancy. On endoscopic ultrasonography, hyperechoic lesion localized to submucosal layer is a diagnostic feature for colonic lipoma. Heterogenous or hypoechoic lesions on endoscopic ultrasound have rarely been described.
On colonoscopy pedunculated or sessile smooth lesion is seen that may shows “pillow” or “cushion” sign when lesion indented with closed biopsy forceps and it promptly reassumes its previous shape on release. Biopsy from the superficial surface may not confirm the diagnosis due to submucosal location of tumor as was seen in our patient.
Small size lipoma (<2 cm) asymptomatic lesions are followed up as there are no features of malignancy. Lipomas of larger size with symptoms require endoscopic or surgical removal. Adipose tissue has little amount of water to conduct electricity during endoscopic snare removal hence larger electrical current is required, that increases the risk of colonic perforation or wall injury. However, inexperienced hands excision of pedunculated lesions is feasible and safe. Partial resections can be done if complete resection is not possible to relieve symptoms. Surgical excision is necessary in sessile lesions, lesions with extensions on the serosa or muscularis propria into the pedicle, or in complicated cases presenting with obstruction or intussusception.
| Conclusion|| |
Rare diagnosed case of symptomatic colonic lipoma needs a multidisciplinary approach. Once the diagnosis is confirmed advance endoscopic techniques and laparoscopic or open excision of lipoma can be done. Laparoscopic resection is the first choice in patients with doubtful preoperative diagnosis, complicated cases like features of obstruction and if endoscopic resection is not possible. Laparoscopic-assisted excision is a good alternative to open conventional surgery as was done in this patient.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
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Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]