Natural evolution of an intraductal papillary mucinous neoplasm of the pancreas. A case report.

Intraductal papillary mucinous neoplasms include a large spectrum of lesions communicating with the Wirsung duct, having a variable invasiveness from benign or borderline, to malignant (carcinoma in situ and invasive cancer). Final diagnosis is based on endoscopic ultrasound (EUS)-guided fine needle aspiration and histopathologic exam of surgical specimens. We present the case of a 28-year-old woman, with several episodes of acute recurrent pancreatitis in the past 6 months, admitted for dyspepsia, nausea and loss of appetite. Imaging studies (transabdominal ultrasonography, CT scanning, MR cholangiopancreatography) showed a macrocystic, multilocular, corporeal tumor, communicating with the retrograde dilated Wirsung duct. EUS revealed hypoechoic material inside the cysts, raising the suspicion of an intraductal papillary mucinous neoplasm. Diagnosis was confirmed by EUS-guided fine needle aspiration, which found columnar mucinous cells within a mucin-rich fluid. The imaging evaluation was repeated after two years, showing a rapid evolution of the tumor. The patient refused surgical exploration and caudal pancreatectomy. In the context of the absence of clinical symptoms, the indolent evolution of these tumors and the excellent prognosis after resection, we consider that early identification and regular follow-up by EUS with fine needle aspiration is imperative, especially because of the limited success of other imaging methods.