Pancreatic heterotopias: clinicopathological analysis of 18 patients.

Objective: To analyze the clinical and pathological features of heterotopic pancreatic tissue in abdominal digestive organs.

Methods: We retrospectively studied 18 patients with histologically diagnosed heterotopic pancreas. Clinical and histopathologic data were reviewed. Heterotopic pancreatic tissues were classified in three histological models: Type I consists of three components of normal pancreas (acini, ducts and islets), type II with two components and type three with only one component.

Results: The mean age was 52.7 years, ranging from 34 to 73 years, nine of them men and nine women. Symptoms were observed in only four patients, and their lesions were diagnosed by gastroscopy. The remaining 14 were asymptomatic and their anomalies were discovered accidentally. Most of the lesions were located in the upper gastrointestinal tract: seven (38.9%) in the stomach, six (33.3%) in the duodenum and three (16.6%) in the jejunum. Heterotopia was mostly located in the submucosa (83.3%) but was also observed in the muscularis propria and in the sub-serosa. In seven specimens (38.9%) all pancreatic components were found (type I), in eight (44.4%) exocrine glands and excretory ducts were present (type II) and in three (16.7%) only exocrine tissue was observed (type III).

Conclusion: Pancreatic heterotopia is rare. Patients with pancreatic ectopia diagnosed by pathological study, whether asymptomatic or with mild symptoms, should be observed. Lesions incidentally detected during surgeries need to be removed by conservative procedures.