Lipomatous polyp causing colo-colic intussusception

INTRODUCTION

Lipoma is the most common benign tumour of soft tissues in the human body. They were first described in 1757, by Bauer.¹ The majority occur in elderly people and are subcutaneous in location. Virtually all organs in the human body could be affected by the pathology. Lipomas in the gastrointestinal tract are rare. The colon is one of these sites. Most are located on the right side of the colon. The caecum and ascending colon are being common sites.^1,2

Colonic lipomas larger than 2 cm may be a cause of bowel obstruction otherwise, they are usually asymptomatic. It is also rare to get benign lesions, which leads to intussusceptions on the left side. Here we are reporting a case of colo-colic intussusceptions with lipoma as a leading point on the sigmoid colon.^1-4

CASE REPORT

This is a 70 years old Ethiopian male patient, who presented with abdominal pain of two weeks duration, which is crampy and intermittent. He has bleeding per rectum of the same duration. He also failed to pass feces and has abdominal distension of five days duration. Otherwise, he has no similar illness before or urinary complaint. No history of cough, fever or other chronic medical illnesses.

On physical examination the patient is acutely sick looking, vital signs were within normal limit. The pertinent finding was on the abdomen; on inspection, there was distension on the lower abdomen, active bowel sound upon auscultation and has tenderness over the left lower quadrant of the abdomen. Per rectal examination showed; Palpable smooth, uniform circumferential mass per rectum with mucous discharge. Otherwise, there was no organomegaly or sign of fluid collection.

Laboratory investigations revealed, WBC=5500, Hgb=13.9 g/dl, CT scan was done and described telescoping of descending colon into the sigmoid colon with a well-defined polyp at the leading point measuring 5 cm in diameter. The polyp has homogeneous fat attenuation. There is a thickening of the bowel walls with minimal stranding of sigmoid mesenteric fat. No free fluid collection in the peritoneal cavity. The CT scan suggested the diagnosis of colo-colic intussusceptions with polyp (lipomatous) as a leading point (Figure 1).

With the above diagnosis, the patient was prepared and abdomen explored through midline vertical incision. The intraoperative findings; colo-colic intussusception with descending colon going into the sigmoid colon with firm mass as leading point palpated but difficulty to reduce (Figure 2). There was firm mass at the tip of the appendix. For this En-block resection of the intussusception to the level of distal descending colon proximally and distal sigmoid colon distally and appendectomy was done and sent for histopathology. Distal stump was closed and proximal stump exteriorized as end colostomy. The patient had a smooth post-operative course and discharged improved after 10 days of stay in the hospital. The colostomy reversed after six weeks and discharged with a smooth course.

The pathology result revealed, microscopy shows lobules of mature adipose tissue with features of inflammation and surface mucosal ulceration (Figure 3). Conclusion colon (segmental resection) lipomatous polyp with features of panniculitis Sections through appendix show extensive neutrophil infiltrates to the muscularis propria with abscess pocket and luminal mucosal plugging. Appendix (appendectomy): acute purulent appendicitis. The lumen of the appendix was obliterated and filled with faecolith.

DISCUSSION

Lipomas of the colon are rare benign tumors of the gastrointestinal tract. Mainly occur in aged people.^1-5 Majority (more than half) of the lipomas are located in the right hemi-colon, in descending order: caecum, ascending colon and transverse colon. Left-sided lesions are more common in males. Our patient: an old male patient sigmoid colon lesion.^3-5 Anatomically 90% of large bowel lipomas are submucosal and the rest subserosal.^1-5

The majority of lipomas are asymptomatic. If they cause symptoms, it is mainly due to size. A large lipoma (>2 cm) could cause; pain, bleeding, and obstruction. If they cause obstruction, it is by intussusceptions. Lipomas are the most common benign neoplasms that cause Intussusception ns in adults. The intussusceptions could be acute or chronic. If chronic usually manifests with bleeding due to ulceration.^1,2,4,5 our patient presented with bleeding, sign and symptoms of acute obstruction. The mass was >2 cm in size.

For diagnosis, computed tomography (CT) scan and colonoscopy are the choices. CT shows fat in the mass. For confirmation, we need a tissue biopsy.^1,3,4 The patient’s CT revealed; a mass with fat and biopsy confirmed it. Small and asymptomatic lipomas of the large bowel do not require surgical management. Symptomatic lipomas should be excised with colectomy or a limited colon resection. That why we need preoperative anticipation of benign lesions for the proper treatment.^1,2,4,5 In our patient limited resection, the colon was done, as there was a suggestion of lipoma with a CT scan.

CONCLUSION

Benign lesions like colonic lipomas should also be kept in mind while evaluating an adult patient with suspected intussusceptions to prevent unnecessary extensive resection. Limited resection is considered as a treatment of choice for lipoma.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: Not required

REFERENCES

1. 1. Dolai MA, Andrejic BM, Ivanov DD. Lipoma of the sigmoid colon. Vojnosanitetski pregled. 2013;70(3):319-21.
2. 2. Crocetti D, Sapienza P, Sterpetti AV, Paliotta A, Gori DA, Pedulla G, et al. Surgery for symptomatic colon lipoma: a systematic review of the literature. Anticancer Res. 2014;34(11):6271-6.
3. 3. Silva RR, Amaral TC, Veiga MA. Giant Colorectal Lipoma of Left Colon: Case Report and Literature Review. J Surg Open Access. 2017;3(3):2470-991.
4. 4. Farai AHH, Sharif AS, Alawi AI. Colocolic Intussusception with Lipoma as Lead Point. Sultan Qaboos University Med J. 2014;22(1063):1-4.
5. 5. Aytac B, Yerci O, Gurel S, Ferik Z. Colonic lipomas mimicking colon cancer. Turk J Pathol. 2010;26(3):196-9.