Ectopic pancreas

Stomach with pancreatic heterotopia, low mag.2

Ectopic pancreas is a gastrointestinal condition characterized by the presence of pancreatic tissue outside its normal location, without any anatomical or vascular connection to the main pancreas. This condition is also known as heterotopic, aberrant, or accessory pancreas. Ectopic pancreas can occur in various regions of the body but is most commonly found in the stomach, duodenum, jejunum, and, less frequently, in the Meckel's diverticulum, esophagus, and ileum.

Etiology

The exact cause of ectopic pancreas is unknown. It is believed to occur during the embryonic development of the gastrointestinal tract. During the fifth to eighth weeks of embryonic development, the pancreas forms from two separate buds off the duodenum. It is hypothesized that ectopic pancreatic tissue arises from the misplacement or migration of these buds during embryogenesis.

Symptoms

In many cases, ectopic pancreas is asymptomatic and is often discovered incidentally during imaging studies, surgeries, or autopsies. When symptoms do occur, they are usually nonspecific and can include abdominal pain, nausea, vomiting, gastrointestinal bleeding, and, rarely, intestinal obstruction. The symptoms are often related to the location of the ectopic tissue and the complications it may cause, such as ulceration, inflammation, or growth of a mass.

Diagnosis

Diagnosis of ectopic pancreas can be challenging due to its nonspecific symptoms and rarity. It is often diagnosed incidentally through endoscopy, ultrasound, CT scan, or magnetic resonance imaging (MRI). Endoscopic ultrasound (EUS) can be particularly useful in identifying ectopic pancreatic tissue within the gastrointestinal wall. Histological examination after biopsy or surgical resection is the definitive method for diagnosing ectopic pancreas, with the identification of pancreatic acini, ducts, and islet cells outside the normal pancreas location.

Treatment

Treatment for ectopic pancreas is not always necessary, especially if the patient is asymptomatic. For symptomatic cases, treatment options depend on the symptoms and complications associated with the ectopic tissue. Surgical resection may be recommended for patients experiencing significant symptoms, complications like obstruction or bleeding, or if there is suspicion of malignancy. Endoscopic resection has also been successfully used in some cases, especially for lesions located in the stomach or duodenum.

Prognosis

The prognosis for individuals with ectopic pancreas is generally good, especially for those who are asymptomatic or who have undergone successful treatment for their symptoms. However, there is a rare risk of malignant transformation of ectopic pancreatic tissue, although this is considered extremely uncommon.