Preoperative diagnosis and staging of pancreatic cancer by endoscopic ultrasonography (EUS): A comparative study with other diagnostic tools

Endoscopic ultrasonography (EUS), ultrasonography (US), computed tomography (CT), and angiography (Angio) were performed in 26 patients with pancreatic cancer which were all resected. Preoperative findings of each diagnostic tools were compared with histological findings. In order to discuss the effectiveness of each body imagings, the preoperative staging of pancreatic cancer was evaluated in direct invasion to the anterior pancreatic capsule and stomach (S), direct invasion to the duodenum (D), direct invasion to the retroperitoneal adjacent vessels (Rp), and regional lymph node metastasis (N). The overall accuracy rate was 77% with EUS (50% with US, 38% with CT, 56% with Angio) in S, 81% with EUS (44% with US, 38% with CT, 63% with Angio) in D, 77% with EUS (58% with US, 42% with CT, 73% with Angio) in Rp, and 65% with EUS (58% with US, 38% with CT) in N. EUS revealed high accuracy rates because EUS images of the whole pancreas, surrounding organs and major vessels were clearly visualized through the gastroduodenal walls. Also, the accuracy rates of Angio in Rp and US in N were almost the same as those of EUS in Rp and N. However, it was difficult for every procedures to diagnose the retroperitoneal perineural invasion. From these results, EUS is one of the most beneficial procedures for detecting of the extent of cancer. EUS is expected to be popularized in the diagnosis and staging of the pancreatic cancer.