Value of respiratory triggered diffusion weighted magnetic resonance imaging in the diagnosis of pancreatic adenocarcinoma

Abstract

Objective To investigate the value of respiratory triggered diffusion weighted magnetic resonance imaging (RT DWI) in the diagnosis of pancreatic adenocarcinoma. Methods Fifty-four patients with histologically confirmed pancreatic ductal adenocarcinoma and 49 healthy volunteers with normal pancreas underwent RT DWI at 3.0 T (b-values=0, 600 s/mm2) in a prospective manner. Apparent diffusion coefficient (ADC) values of normal pancreas head, body and tail as well as ADC values of the pancreatic adenocarcinoma were measured and calculated. The ADC values between the different anatomical regions of normal pancreas and pancreatic adenocarcinoma were analyzed by using Mann-Whitney U test. Receiver-operating characteristic (ROC) curve analyses were used to determine the diagnostic performances of ADCs to distinguish pancreatic adenocarcinoma from normal pancreas. Results The ADC values were (1.66±0.34), (1.77±0.36) and (1.62±0.38)×10-3 mm2/s in normal pancreas head, body and tail, and the ADC value of pancreatic adenocarcinoma was (1.36±0.14)×10-3 mm2/s, and the ADC values differed significantly between pancreatic adenocarcinoma and normal pancreas (P<0.000). With the ADC values of normal pancreatic head, body and tail as references, the areas under the curve (AUC) were 0.767, 0.889 and 0.737, respectively. The sensitivity and specificity were 83.7% and 81.5%, respectively, when ADC≤1.485×10-3 mm2/s was used as the cut off value for differential diagnosis of pancreatic adenocarcinoma from normal pancreas body. Conclusions RT DWI has a better diagnostic accuracy in the diagnosis of pancreatic ductal adenocarcinoma. The ADC value of normal pancreas body is recommended as a control. Key words: Pancreatic neoplasms; Diffusion magnetic resonance imaging; Respiratory triggered; Comparative study