Clinical application of contrast-enhanced ultrasound in differential diagnosis of serous pancreatic neoplasia

Objective To investigate the value of contrast-enhanced ultrasound (CEUS) in the differential diagnosis of pancreatic neoplasia (SPN) before operation. Methods Forty-six cases of SPN confirmed by operation and histopathological results from January 2012 to June 2018 were enrolled in the study. According to the European Ultrasound Association (EFSUMB) guidelines for CEUS in 2018, the enhancement pattern of pancreatic lesion with normal surrounding pancreatic parenchyma was used for reference. The enhancement pattern of SPN were observed during the arterial phase, venous phase and delayed phase. CEUS pattern of 16 cases with pancreatic ductal adenocarcinoma (PDAC) with cystic changes proved by histopathology were observed and compared with SPN. Results The mean size of 46 cases of SPN was (32.72±25.51)mm. Fifteen SPN lesions located in the head of pancreas, 31 cases located in the body and tail of the pancreas. Most of SPN were solidcystic lesions with thin separation on conventional B mode ultrasoud, without communication with the main pancreatic duct. Color flow signals could be detected in 78.3% (36/46) SPN lesions. After the injection of 2.4 ml ultrasound contrast agent, the substantial part of all SPN showed hyperenhancement (n=44, 99.7%) or isoenhancement (n=2, 4.3%) during the arterial phase, venous phase and late phase. However, 93.8% (15/16) of the PDAC lesion with cystic changes showed consistent hypo enhancement throughout the arterial, venous and late phase (P<0.05). The accuracy of preoperative diagnosis of CEUS was 95.6%. Conclusions Depending on its unique advantages such as real-time observation, high-resolution imaging, and no radiation, CEUS is helpful for early detection, accurate localization and preoperative diagnosis of SPN. CEUS has potential role for clinical decision-making before treatment. Key words: Contrast-enhanced ultrasound; Serous pancreatic neoplasia; Pancreatic ductal adenocarcinoma; Differential diagnosis