[A case of pancreatic mucinous cystic neoplasm that enlarged during pregnancy and was resected after childbirth].

A 28-year-old pregnant woman presented with an abdominal mass at 12 weeks' gestation. Magnetic resonance imaging revealed a 7 cm cystic lesion arising extrinsically from the pancreatic head, which was diagnosed as a mucinous cystic neoplasm. Although we recommended surgical excision during the second trimester, the patient refused the procedure and chose to continue her pregnancy. We monitored the lesion and noted that it gradually grew to 13 cm over the course of the pregnancy. Subsequently, we enucleated it after childbirth. Histopathological examination was compatible with high-grade dysplasia and confirmed the diagnosis of mucinous cystadenoma of the pancreas.