Abstract
The diagnosis of early pancreatic cancer is essential for an appropriate surgical treatment. One of the crucial moments in the diagnostic process is to distinguish pancreatic carcinoma from other tumors.
However, the conventional B-mode image without fine needle biopsy gives unsatisfying sensitivity. Therefore, a new non-invasive method is needed.
The main aim of this study is to investigate the sensitivity of contrast enhanced endoscopic ultrasound (cEUS) in differentiating pancreatic cancer from benign lesions and to compare it with the sensitivity of EUS. The secondary aim is to find out what is the interpersonal agreement in the evaluation of cEUS.
We examined 54 patients. During the EUS procedure, the details of solid lesion were described.
We focused on the irregular edge, hypoechogenicity and inhomogeneity. Then, 2.4 ml of Sono Vue was applied and followed by a cEUS observation and evaluation.
Every patient has undergone fine needle aspiration (FNA) of the lesion at the end of the procedure. The pancreatic solid lesions were divided into three vascular patterns - hypovascular, isovascular and hypervascular.
These patterns and EUS signs of malignancy were compared to the final histological or cytological diagnosis to assess the sensitivity. Cytology proved 35 pancreatic cancers, 5 neuroendocrine tumors, 3 chronic pancreatitises, 1 duodenal and 1 gastric carcinoma and 1 solid pseudopapillary tumor.
Eight other lesions were cystic so they were excluded. In the group of 46 solid tumors, the sensitivity of cEUS in the detection of pancreatic cancer was 97.1%.
The interobservation agreement of two endosonographers was better in EUS than in cEUS (kappa 0.640 vs. 0.450). cEUS is an effective and accurate method to differentiate pancreatic cancer from other pancreatic solid masses with high sensitivity. Even if the interobservation agreement in cEUS is worse than in EUS, it is good enough to make the appropriate final statement.