Background: A lipoma is one of the commonest benign tumors in surgical practice. Lipomas are usually
found on the trunk and limbs but less commonly within the abdomen, where they occur frequently in the
mesentery as well as the subserosa and submucous layer of the gastrointestinal tract. Pre-peritoneal lipomas
are rare.
Case Presentation: A 44-year-old woman presented with a painless and progressive right-sided abdominal
swelling of 5 months duration. Examination revealed a 16cm x 14cm slightly mobile and non-tender firm-to-hard hour-glass-shaped mass extending from the right hypochondrial to right iliac and the suprapubic
regions. Abdominal ultrasonography showed a 5cm x 6cm bowel thickening in the right iliac fossa
suggestive of an ileocecal mass while a computerized tomography showed a 20.8cm x 6.3cm x 20.1cm
hypodense mass within the peritoneal cavity, extending from the epigastric region to the pelvis, anterior to
the bowel loops and more to the right. At laparotomy, a huge, well encapsulated yellowish mass in the pre-peritoneal space, weighing 1,520g was excised. Histology confirmed a lipoma.
Conclusion: A preperitoneal lipoma is an uncommon soft tissue tumor and the giant ones are extremely
rare. Although a rare cause of a painless abdominal swelling, pre-peritoneal lipoma should be considered as
a differential diagnosis in patients presenting with an unremarkable feature suggestive of an intra-abdominal
pathology.