Teaching Case

A 44-year-old male was found during a routine exam to have a large multilocular intra-abdominal cyst on abdominal ultrasound. He was otherwise asymptomatic.

A 44-year-old male was found during a routine exam to have a large multilocular intra-abdominal cyst on abdominal ultrasound. He was otherwise asymptomatic and there were no abnormal signs on physical examination. The laboratory investigations were normal. His tumor markers, including alfa-feto-protein, carcino-embrionic antigen were not elevated. The patient was then referred for total colonoscopy that was normal. Barium studies show a smoothly marginated mural mass at transverse colon.   A CT scan revealed a large 4 cm, well-circumscribed, cyst arising from the transverse colon with enhancement of the wall and septum by contrast medium. The cyst contents had an attenuation of 10-20 HU, corresponding to fluid. At surgery a 4 cm multiloculated cyst in the transverse colon was identified. Pathologic examination revealed findings compatible with a colonic lymphangioma.  

Lymphangiomas are rare tumours. As many as 90% manifest before the age of three and the sex ratio is roughly equal in childhood. In young patients lymphangiomas are preferentially located in head, neck and axilla, but they also occur sporadically in various parenchymal organs (e.g. spleen, liver, bones), sometimes as a diffuse or multifocal disease (lymphangiomatosis). During adulthood, they mostly appear as superficial cutaneous lymphangioma or as intraabdominal lymphangiomas. There is a male to female ratio for intraabdominal lymphangiomas of 3:1. Intraabdominal lymphangiomas are rare tumours, accounting for approximately 1 per 100.000 hospital admissions. They occur in the mesentery of the small and large bowel but also at retroperitoneal sites. The clinical symptoms range from chronic to acute abdominal pain sometimes due to perforation, obstruction or anaemia due to hemorrhage. Traditionally, lymphangiomas are classified as simple, cavernous, or cystic. Although benign in nature, mesenteric lymphangiomas may cause significant morbidity or mortality due to their large size and critical location, when they compress the adjacent structures. In addition, complications such as secondary infection, rupture with hemorrhage, volvulus, or intestinal obstruction have all been reported. The ultrasonographic presentation of a mesenteric lymphangioma is described as a cystic lesion with multiple thin septa. The use of EUS has also revolutionized the detection of mucosal and submucosal lesions in the GI tract and it has been shown to be extremely useful in the diagnosis of GI lymphangiomas which are submucosal tumors. The EUS appearance has been typically described as an anechoic septated tumor arising from the third sonographic layer (submucosa). On CT imaging, mesenteric lymphangiomas appear as a uni- or multilocular mass with enhancement of the wall and septum by contrast medium. Differential diagnosis may include a cystic mass such as a pancreatic pseudocyst, duplication cyst, mesenteric cyst and anexial cyst. Although benign in nature, complete surgical excision at laparotomy is the treatment of choice of intra-abdominal lymphangiomas. Several less invasive modes of treatment such as aspiration, sclerotherapy, drainage, and irradiation have been proposed but are associated with high recurrence rates. Recently, with advances in minimally invasive surgery, laparoscopic resection of mesenteric and retroperitoneal cysts including lymphangiomas has been reported.