[Rapid growth and malignant transformation of a mucinous cystic neoplasm during pregnancy - a case report].

BACKGROUND Mucinous-cystic neoplasms (MCN) account for 10% of all pancreatic cystic lesions. They are found almost exclusively in females. MCN have an ovarian-like stroma and often estrogen and progesterone receptors. During pregnancy, they can massively increase in size and transform into malignancy. CASE REPORT We report on a 29-year-old woman in whom a 35mm cyst in the pancreatic tail had been diagnosed several years ago. After workup the lesions had been classified as a pseudocyst. During pregnancy, the cyst massively increased in size and finally was resected. Histology showed a mucinous-cystic neoplasia with focal malignant transformation. CONCLUSION Cystic neoplasms of the pancreas require a differentiated management. While overtreatment should be avoided, malignant transformation always merits consideration - in particular if the cystic lesion is located in the pancreatic tail. Women with suspected MCN or cystic pancreatic lesions of uncertain etiology should be informed about the (rare) risk of a malignant transformation of an MCN and should be closely monitored during pregnancy.