Value of DWI on differentially diagnosing malignant and benign mucinous cystic neoplasms of pancreas

Objective：To explore the value of diffusion weighted imaging (DWI) on differentially diagnosing malignant and benign mucinous cystic neoplasms of pancreas. Methods：Forty-five patients with pancreatic mucinous cystic neoplasms who underwent DWI were included retrospectively. The apparent diffusion coefficient (ADC) values of tumor were measured and the ADCmean, ADCmin, and ADCmaxwere compared between malignant and benign tumors. Receiver operator characteristics (ROC) analysis was further performed for evaluating diagnostic performance. Results：The ADCmeanof benign pancreatic mucinous cystic neoplasms(n=27)was significantly higher than that of malignant neoplasms (n=18; 3.34×10-3 mm2/s vs 2.36×10-3 mm2/s，P<0.000 1), with area under the ROC curve (AUC) of 0.91. The ADCmin of malignant pancreatic mucinous cystic neoplasms was also significantly lower than that of benign neoplasms (1.24×10-3 mm2/s vs 2.54×10-3 mm2/s, P<0.000 1), with AUC of 0.94. While no significant difference of ADCmax was found between benign and malignant neoplasms (3.71×10-3 mm2/s vs 3.86×10-3 mm2/s). Conclusions：ADCmean and ADCmin are useful for differentially diagnosing malignant and benign mucinous cystic neoplasms of pancreas in DWI.