OR-HPB-06: Time intensity enhancement patterns of solid pancreatic tumors with the use of contrast-enhanced harmonic endoscopic ultrasonography

BACKGROUND AND OBJECTIVES: Contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) was reported as a useful tool for differential diagnosis of pancreatic tumor. However, the time to evaluate the intensity of enhancement is still uncertain. The aim of this study was to evaluate the vascularization patterns of solid pancreatic tumors. METHODS: A total 46 patients who underwent CH-EUS for solid pancreatic tumors (pancreatic adenocarcinoma [PDAC] 33, pancreatic neuroendocrine tumor [PNET] 8, autoimmune pancreatitis [AIP] 5) were retrospectively analyzed. We examined maximum/minimum intensity (Max-I/Min-I), time to peak intensity (TTP), and time to start washout (TTW) of the lesions. RESULTS: Max-I of CH-EUS showed isoenhancement pattern in 21 cases (64%) of PDAC and five cases (100%) of AIP. On the other hand, Max-I of NET showed hyperenhancement pattern in six cases (75%). Min-I of CH-EUS showed hypoenhancement pattern in 23 cases (70%) of PDAC, four cases (80%) of AIP, and five cases (63%) of NET. Median TTP of each solid pancreatic tumor was PDAC (22 s), AIP (20 s), and NET (17 s). Median TTW for PDAC was 38 s, AIP 45 s, and NET 33 s. CONCLUSIONS: TTP/TTW was different depending on each tumor. Further study is warranted to clarify the time intensity patterns.