A pancreatic rest is a type of submucosal nodule in which pancreatic tissue develops under the lining, or mucosa, of another organ, such as the stomach or small intestine. This condition is also known as aberrant pancreas, heterotopic pancreas, or ectopic pancreas.
Most pancreatic rests have no symptoms, but in some cases, they can cause pancreatitis, ulcers, bleeding, or obstruction of the affected organ. Generally, pancreatic rests that cause no symptoms do not require treatment. However, because pancreatic rests can look similar to other submucosal nodules on imaging tests, a biopsy procedure called endoscopic ultrasound-guided fine needle aspiration, or EUS-FNA, may be recommended to rule out a cancerous growth.