Diagnostic value of endoscopic ultrasonography for pancreatic cystic lesions / 中华胰腺病杂志

ABSTRACT

Objective:To explore the diagnostic value of endoscopic ultrasonography (EUS) for pancreatic cystic lesions (PCLs).Methods:Clinical data of 211 patients with PCLs, who underwent EUS at least once and were pathologically confirmed in First Affiliated of Naval Medical University from January 2011 to December 2021 was retrospectively analyzed. EUS imaging characteristics, biochemical analysis of cystic fluid and pathological data were recorded. The pathological diagnosis results of intraductal papillary mucinous neoplasms and mucinous cystic neoplasms were included in the mucinous lesion group, while pancreatic pseudocyst, serous cystic neoplasms, solid pseudopapillary neoplasms and pancreatic neuroendocrine tumors were included as non-mucinous lesions group; those with pancreatic ductal adenocarcinoma, adenocarcinoma or with atypical or cancer cells were included as malignant lesion group, and the else were included as benign lesions group. The level of CEA in cyst fluid between mucinous and non-mucinous lesions and the level of amylase in cyst fluid between benign and malignant lesion groups were compared, and the area under the curve (AUC) was calculated by drawing receiver operating characteristic curve (ROC), which was used to analyze the differential diagnosis efficiency of cyst fluid CEA and amylase test indexes. The basic characteristics and EUS imaging characteristics, and the diagnostic efficiency of EUS and liquid-based cytology and histopathology between benign and malignant lesions were studied and analyzed.Results:Among the 211 PCL patients, cyst fluid was obtained in 201 patients, of which 188 patients (93.5%) underwent cytological examination, and 33 patients were diagnosed with an accuracy rate of 17.6%; 41 cases were obtained for histological examination, and 23 cases were confirmed, with an accuracy rate of 56.1%. Among all confirmed cases, 45 cases had benign lesions, including 22 cases of mucinous lesions and 23 cases of non-mucinous lesions, with the cyst fluid CEA of 1458.16(19.80, 1500.00), 4.4(0.50, 341.14)ng/ml respectively, and the difference of cyst fluid CEA level between mucinous and non-mucinous lesions was statistically significant( P<0.05). The cyst fluid CEA<10.15 ng/ml could be used to diagnose non-mucinous PCLs with the sensitivity of 89.5%(95% CI0.686-0.981), and the specificity of 66.7%(95% CI0.438-0.837). The cyst fluid amylase levels in benign and malignant lesions were 379.00(50.00, 18405.50), 42.00(13.50, 340.00)U/L, and the difference was statistically significant ( P<0.05). The cyst fluid amylase>747.50 U/L might help to identify benign PCLs with the sensitivity of 91.7%(95% CI0.646-0.996), and the specificity of 48.0%(95% CI0.300-0.665). EUS showed that the proportion of cyst wall thickening, main duct dilatation and cystic solid components in patients with malignant lesions was significantly higher than that in patients with benign lesions, and the differences were statistically significant ( P<0.05), while there was no significant difference in the proportion of cyst wall nodules and cystic septum between the two groups. The accuracy of EUS combined with liquid-based cytology or histopathology in malignant lesions was over 80%. Conclusions:The cyst fluid CEA level can help to differentiate non-mucinous PCLs from mucinous PCLs, and the cystic amylase level could be useful to identify the benign and malignant PCLs. EUS combined with cytology or histology had high diagnostic value for malignant or potentially malignant PCLs, and EUS-FNA examination can be recommended as soon as possible for those with high-risk factors.