What could cause a cyst in the epigastric region?

A cyst is a closed sac filled with fluid that can develop in the upper part of your abdomen under the sternum. There are several potential causes: sometimes these cysts are congenital, meaning they are present from birth, such as gastrointestinal duplication cysts that occur when part of the digestive tract is duplicated. Other times, a cyst might develop after an episode of inflammation—for example, a pancreatic pseudocyst can form following pancreatitis. Mesenteric cysts, which arise in the tissue that supports the intestines, are another possibility. These are often benign and may not cause problems right away, though they can sometimes lead to discomfort, a feeling of fullness, or pain if they grow large. Imaging studies, like an ultrasound or CT scan, are usually needed to determine the type and exact location of the cyst. Although most cysts in this region are not cancerous, it is important to get any new or unusual abdominal mass evaluated—you can start by using our free symptom checker to better understand your symptoms before consulting with a healthcare provider to decide if treatment or monitoring is needed.