Published online May 21, 2019. doi: 10.3748/wjg.v25.i19.2271
Peer-review started: January 7, 2019
First decision: March 14, 2019
Revised: March 30, 2019
Accepted: April 19, 2019
Article in press: April 19, 2019
Published online: May 21, 2019
Pancreatic cystic lesions (PCLs) have been increasingly recognized in clinical practice. Although inflammatory cysts (pseudocysts) are the most common PCLs detected by cross-sectional imaging modalities in symptomatic patients in a setting of acute or chronic pancreatitis, incidental pancreatic cysts with no symptoms or history of pancreatitis are usually neoplastic cysts. For these lesions, it is imperative to identify mucinous cysts (intraductal papillary mucinous neoplasms and mucinous cystic neoplasms) due to the risk of their progression to malignancy. However, no single imaging modality alone is sufficient for a definitive diagnosis of all PCLs. The cyst fluid obtained by endoscopic ultrasound-guided fine needle aspiration provides additional information for the differential diagnosis of PCLs. Current recommendations suggest sending cyst fluid for cytology evaluation and measurement of carcinoembryonic antigen (CEA) levels. Unfortunately, the sensitivity of cytology is greatly limited, and cyst fluid CEA has demonstrated insufficient accuracy as a predictor of mucinous cysts. More recently, cyst fluid glucose has emerged as an alternative to CEA for distinguishing between mucinous and nonmucinous lesions. Herein, the clinical utility of cyst fluid glucose and CEA for the differential diagnosis of PCLs was evaluated.
Core tip: Incidental pancreatic cysts have been found in far more patients with the improvement of cross-sectional imaging tests. Many of these lesions have malignant potential, especially the mucinous lesions, and imaging alone is not enough to guarantee definitive diagnosis. Cyst fluid carcinoembryonic antigen (CEA) has been used as the most important cyst fluid marker to distinguish mucinous from nonmucinous cysts. More recently, glucose has emerged as a useful cyst fluid marker for the identification of pancreatic mucinous cysts with an accuracy similar to or even better than CEA.