Comparison of IV contrast-enhanced sonography and histopathology of pancreatic cancer

OBJECTIVE. We compared contrast-enhanced sonography findings with pathologic findings in pancreatic cancer to evaluate the ability of contrast-enhanced sonography to depict the pathologic changes associated with pancreatic cancer. SUBJECTS AND METHODS. Thirty-four patients with pancreatic cancer who underwent surgery were investigated. Sonography was performed with contrast material (Levovist) for all patients before surgery. Pathologic findings were evaluated on the basis of the resected cancer specimens. We compared contrast-enhanced sonography findings with pathologic findings. RESULTS. All tumors that were hyperechoic on contrast-enhanced sonography were papillary adenocarcinoma, and all tumors that were hypoechoic on contrast-enhanced sonography were ductal adenocarcinoma. Among ductal adenocarcinomas, five (71.4%) of seven tumors for which the size of the hypoechoic area was unchanged on contrast-enhanced sonography had clear tumor margins with no infiltration or inflammation in the margin. In contrast, all tumors for which the size of the hypoechoic area was reduced on contrast-enhanced sonography had unclear tumor margins with infiltration of cancerous cells and inflammation. Nine (90%) of 10 tumors that showed partial contrast enhancement or a vascular shadow in a hypoechoic area had large or medium-sized vessels within a tumor at pathology. In contrast, only one (4.8%) of 21 tumors that did not show the vascular shadow in a hypoechoic area had no large or medium-sized vessels in a tumor. CONCLUSION. Contrast-enhanced sonography well reflects the pathologic changes of pancreatic cancer and will provide useful information in a pretreatment evaluation. Further studies with a large number of patients will be required to confirm this finding.