Pancreatic adenocarcinoma with intratumoral anechoic components will increase the number of endoscopic ultrasound-guided fine-needle aspiration passes

Background For diagnosis of pancreatic cancer, endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is currently the standard procedure because of its safety and reliability. But on considering cost, time, and risk of complications of EUS-FNA, the number of aspiration passes should be minimized. Previously, only tumor differentiation and the site of aspiration have been recognized as major determinants that influence the number of needle passes during EUS-FNA for pancreatic malignancy. The aim of this study was to prospectively evaluate factors affecting the number of passes in patients with pancreatic cancer.

Methods Between May 2003 and December 2004, 41 patients with presumed pancreatic cancer were studied. EUS-FNA was performed with an Olympus GF-UC2000P echoendoscope and a 22-gauge needle. An on-site cytopathologist was available during the procedure for assessment of the specimen.

Results Twenty five patients were diagnosed as pancreatic adenocarcinoma, and the ones with intratumoral anechoic components required a higher number of diagnostic passes than those without anechoic change (3.40 vs. 2.27, p <0.05). An average of 4.00 fine-needle aspiration passes for diagnosing a well-differentiated adenocarcinoma was also significantly higher than the 2.40 diagnostic passes for a moderately differentiated adenocarcinoma and the 2.00 passes for a poorly differentiated one (p <0.05).

Conclusions The existence of intratumoral anechoic components was not a rare finding under detailed EUS investigation of pancreatic ductal adenocarcinomas. Both the existence of small anechoic components and the differentiation of the cancer are significantly predictive for higher number of diagnostic passes in performing EUS-FNA of pancreatic cancer.