Pancreatic cystic lesions without overt cytologic atypia: proposed diagnostic categories for endoscopic ultrasound-guided fine-needle aspiration cytology with utilization of fluid carcinoembryonic antigen level.

OBJECTIVES

It was the aim of this study to examine pancreatic cyst cases that lack markedly atypical or malignant epithelium on endoscopic ultrasound-guided fine-needle aspirations.

STUDY DESIGN

We conducted a retrospective case review study, including 24 cases that were either acellular or lacked cytologic atypia and were subsequently resected. The cases were retrospectively divided into 3 categories: (1) non-diagnostic, (2) cyst contents only, and (3) cyst contents with bland-appearing epithelium. The cyst contents were subdivided into mucinous and non-mucinous types. The cytologic diagnoses were correlated with cyst fluid carcinoembryonic antigen (CEA) levels and subsequent histologic diagnoses.

RESULTS

Category 1 comprised 4 cases: 2 cases (CEA >800 ng/ml) with mucin-producing neoplasms and 2 cases (CEA not determined) with microcystic serous cystadenomas. Category 2 included 4 cases with non-mucinous and 4 with mucinous contents. In the first subgroup, 2 cases (CEA >800 ng/ml) showed mucinous cystic neoplasms and 2 cases (CEA negligible or not determined) pseudocysts. In the second subgroup, there were 3 cases with neoplastic mucinous cysts (1 CEA >800 ng/ml, 2 not determined) and 1 case with a lymphoepithelial cyst with mucinous metaplasia (CEA >800 ng/ml). Almost all cases (10/11) in category 3 had neoplastic mucinous cysts regardless of the CEA levels.

CONCLUSIONS

The proposed 3 cytologic categories of pancreatic cystic lesion combined with cyst fluid CEA levels provide useful clinical information.