A rare case of pancreatic mucinous cystic neoplasm in a pediatric patient.

Pancreatic mucinous cystic neoplasms (MCNs) are rare tumors predominantly identified in middle-aged females. Occurrences are extremely rare in children. We report a rare case of pancreatic MCN in an adolescent. A 14-year-old female with Smith-Magenis syndrome and steatotic liver disease (SLD) presented with abdominal discomfort. Magnetic resonance elastography obtained for SLD revealed cholelithiasis and a 0.5-cm cyst in the distal pancreas. Observation was recommended by her pediatric surgery provider. At 18 years old, contrast-enhanced abdominal magnetic resonance imaging showed a 2.4-cm mildly complex, septate, cystic lesion along the distal pancreas with no soft tissue component, pancreatic atrophy, or ductal dilation. Endoscopic ultrasound with cyst fluid cytology showed no definitive neoplasm. Carcinoembryonic antigen level of cyst fluid was markedly elevated at 11,207 ng/mL, concerning an MCN. She was referred to Hepatopancreatobiliary Surgery for evaluation and underwent robotic-assisted distal pancreatectomy. Final pathology revealed a 2.8-cm low-grade MCN with intermediate-grade dysplasia.