Pancreatic acinar cell cystadenoma: single-center experiences and a systematic review

AIMS: Pancreatic cystic lesions (PCLs) range from benign to malignant, creating diagnostic and therapeutic challenges. While most PCLs are serous or mucinous neoplasms, rare entities such as acinar cell cystadenoma (ACC) remain poorly characterized. This study reports a tertiary center cohort and a systematic literature review. METHODS: We retrospectively analyzed 23 ACC patients at Karolinska University Hospital. A systematic review was performed following PRISMA guidelines. RESULTS: In our cohort (median age 67.0 years; 73.9% male), ACCs were most often incidentally detected, with abdominal pain being the most frequent indication for imaging. No patients underwent surgery, and no malignant transformation was observed during a median follow-up of 10.4 months. Most patients (87%) underwent both CT and MR imaging, and 65.2% fulfilled proposed imaging diagnostic criteria.The systematic review included 41 studies with 165 patients. Abdominal pain was the most common indication for imaging, and most patients underwent pancreatic surgery. Median follow-up was 1.3 years, with no malignant transformation observed. Imaging typically showed well-circumscribed cystic lesions, usually non-communicating with the main pancreatic duct and mimicking other cystic neoplasms. Histopathology consistently demonstrated an acinar phenotype with low proliferative activity. CONCLUSIONS: ACC appears to be an asymptomatic, incidentally discovered lesion, with imaging playing a central diagnostic role. Neither endocrine nor exocrine pancreatic insufficiency nor malignant transformation was observed. However, the relatively short overall follow-up limits conclusions regarding long-term outcomes.