Ectopic pancreas at the ampulla of Vater diagnosed with endoscopic snare papillectomy: A case report and review of literature

BACKGROUND: Ectopic pancreas is a rare developmental anomaly that results in a variety of clinical presentations. Patients with ectopic pancreas are mostly asymptomatic, and if symptomatic, symptoms are usually nonspecific and determined by the location of the lesion and the various complications arising from it. Ectopic pancreas at the ampulla of Vater (EPAV) is rare and typically diagnosed after highly morbid surgical procedures such as pancreaticoduodenectomy or ampullectomy. To our knowledge, we report the first case of confirmed EPAV with a minimally invasive intervention. CASE SUMMARY: A 71-year-old male with coronary artery disease, presented to us with new-onset dyspepsia with imaging studies revealing a ‘double duct sign’ secondary to a small subepithelial ampullary lesion. His hematological and biochemical investigations were normal. His age, comorbidity, poor diagnostic accuracy of endoscopy, biopsies and imaging techniques for subepithelial ampullary lesions, and suspicion of malignancy made us acquire histological diagnosis before morbid surgical intervention. We performed balloon-catheter-assisted endoscopic snare papillectomy which aided us to achieve en bloc resection of the ampulla for histopathological diagnosis and staging. The patient’s post-procedure recovery was uneventful. The en bloc resected specimen revealed ectopic pancreatic tissue in the ampullary region. Thus, the benign histopathology avoided morbid surgical intervention in our patient. At 15 mo follow-up, the patient is asymptomatic. CONCLUSION: EPAV is rare and remains challenging to diagnose. This rare entity should be included in the differential diagnosis of subepithelial ampullary lesions. Endoscopic en bloc resection of the papilla may play a vital role as a diagnostic and therapeutic option for preoperative histological diagnosis and staging to avoid morbid surgical procedures.