title: Heterotopic Pancreas: Histopathologic Features, Imaging Findings, and Complications.
abstract: Heterotopic pancreas is a congenital anomaly in which pancreatic tissue is anatomically separate from the main gland. The most common locations of this displacement include the upper gastrointestinal tract-specifically, the stomach, duodenum, and proximal jejunum. Less common sites are the esophagus, ileum, Meckel diverticulum, biliary tree, mesentery, and spleen. Uncomplicated heterotopic pancreas is typically asymptomatic, with the lesion being discovered incidentally during an unrelated surgery, during an imaging examination, or at autopsy. The most common computed tomographic appearance of heterotopic pancreas is that of a small oval intramural mass with microlobulated margins and an endoluminal growth pattern. The attenuation and enhancement characteristics of these lesions parallel their histologic composition. Acinus-dominant lesions demonstrate avid homogeneous enhancement after intravenous contrast material administration, whereas duct-dominant lesions are hypovascular and heterogeneous. At magnetic resonance imaging, the heterotopic pancreas is isointense to the orthotopic pancreas, with characteristic T1 hyperintensity and early avid enhancement after intravenous gadolinium-based contrast material administration. Heterotopic pancreatic tissue has a rudimentary ductal system in which an orifice is sometimes visible at imaging as a central umbilication of the lesion. Complications of heterotopic pancreas include pancreatitis, pseudocyst formation, malignant degeneration, gastrointestinal bleeding, bowel obstruction, and intussusception. Certain complications may be erroneously diagnosed as malignancy. Paraduodenal pancreatitis is thought to be due to cystic degeneration of heterotopic pancreatic tissue in the medial wall of the duodenum. Recognizing the characteristic imaging features of heterotopic pancreas aids in differentiating it from cancer and thus in avoiding unnecessary surgery.©RSNA, 2017.
authors.affiliation: From the Department of Radiology, University of Utah, 30 North 1900 East, #1A71, Salt Lake City, UT 84132 (M.R., J.D.O., A.M.S.); Department of Radiology, Mayo Clinic, Scottsdale, Ariz (C.M.); Department of Radiology, Indiana University School of Medicine, Indianapolis, Ind (K.S.); and Department of Radiology, MD Anderson Cancer Center, Houston, Tex (K.M.E.).
authors.forename: Maryam
authors.initials: M
authors.lastname: Rezvani
authors.affiliation: From the Department of Radiology, University of Utah, 30 North 1900 East, #1A71, Salt Lake City, UT 84132 (M.R., J.D.O., A.M.S.); Department of Radiology, Mayo Clinic, Scottsdale, Ariz (C.M.); Department of Radiology, Indiana University School of Medicine, Indianapolis, Ind (K.S.); and Department of Radiology, MD Anderson Cancer Center, Houston, Tex (K.M.E.).
authors.forename: Christine
authors.initials: C
authors.lastname: Menias
authors.affiliation: From the Department of Radiology, University of Utah, 30 North 1900 East, #1A71, Salt Lake City, UT 84132 (M.R., J.D.O., A.M.S.); Department of Radiology, Mayo Clinic, Scottsdale, Ariz (C.M.); Department of Radiology, Indiana University School of Medicine, Indianapolis, Ind (K.S.); and Department of Radiology, MD Anderson Cancer Center, Houston, Tex (K.M.E.).
authors.forename: Kumaresan
authors.initials: K
authors.lastname: Sandrasegaran
authors.affiliation: From the Department of Radiology, University of Utah, 30 North 1900 East, #1A71, Salt Lake City, UT 84132 (M.R., J.D.O., A.M.S.); Department of Radiology, Mayo Clinic, Scottsdale, Ariz (C.M.); Department of Radiology, Indiana University School of Medicine, Indianapolis, Ind (K.S.); and Department of Radiology, MD Anderson Cancer Center, Houston, Tex (K.M.E.).
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Olpin
authors.affiliation: From the Department of Radiology, University of Utah, 30 North 1900 East, #1A71, Salt Lake City, UT 84132 (M.R., J.D.O., A.M.S.); Department of Radiology, Mayo Clinic, Scottsdale, Ariz (C.M.); Department of Radiology, Indiana University School of Medicine, Indianapolis, Ind (K.S.); and Department of Radiology, MD Anderson Cancer Center, Houston, Tex (K.M.E.).
authors.forename: Khaled M
authors.initials: KM
authors.lastname: Elsayes
authors.affiliation: From the Department of Radiology, University of Utah, 30 North 1900 East, #1A71, Salt Lake City, UT 84132 (M.R., J.D.O., A.M.S.); Department of Radiology, Mayo Clinic, Scottsdale, Ariz (C.M.); Department of Radiology, Indiana University School of Medicine, Indianapolis, Ind (K.S.); and Department of Radiology, MD Anderson Cancer Center, Houston, Tex (K.M.E.).
authors.forename: Akram M
authors.initials: AM
authors.lastname: Shaaban
mesh_terms: D002828:Choristoma / Q000000981:diagnostic imaging*; D003287:Contrast Media; D003937:Diagnosis, Differential; D006801:Humans; D008279:Magnetic Resonance Imaging; D010179:Pancreas; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media