What is a mesenteric cyst?

Answer 1

These are cysts of the peritoneal area and often are in the mesentery and omentum near the small intestine. They are one of the rarest of abdominal tumors. They may originate in lymph glands, but can be different types of cysts with different causes, too. The most common initial symptom is lower abdominal pain, but often manifest also with vomiting and constipation. The symptoms may come on very suddenly. These can be very large before they are noticed or cause symptoms, often the "size of a child's head", but they can be both smaller or larger than that.

There are no medical conservative treatments and usually surgical treatment is the only option. 50-60% of children with mesenteric cysts require a portion of the bowel to be removed with the cyst to assure all tissue left is normal, but this is only needed in approximately one third of adult cases.

Surgical removal usually involves excision of the entire cyst, but sometimes that isn't possible due to the location or size of the tumor. With the prenatal ultrasounds being done, these can now be found while the fetus is still in the uterus, although no "in utero" surgical treatment can be given at this time. Surgery will usually be scheduled during early infancy to prevent potential complications such as intestinal obstruction.

They can recur after surgery, but infrequently. According to Medscape.com:

"Overall results in pediatric patients are favorable. The recurrence rate ranges from 0-13.6%, averaging about 6.1% in a series of 162 adults and children. Most recurrences occur in patients with retroperitoneal cysts or those who had only a partial excision. Essentially, no mortality is associated with mesenteric or omental cysts in children; only one pediatric death has been reported since 1950. In a series from Egleston Children's Hospital in Atlanta, no major postoperative complications, recurrences, or deaths occurred."

See below for a link to the full Medscape article.