Evaluating the ability to detect pancreatic lesions using a special ultrasonography examination focusing on the pancreas

- To detect pancreatic cancer at an early stage, effective screening programs are needed.
- Although ultrasonography is a useful screening method, its sensitivity is not satisfactory.
- The gastric gas reduces the ability of ultrasonography to detect pancreatic lesions.
- We have developed the new method of ultrasonography by ingesting liquid to stomach.
- The new method had higher sensitivity to detect pancreatic lesions.

PurposeThe ability to detect pancreatic cysts was compared between special ultrasonography (US) examination focusing on the pancreas (special pancreatic US) and routine upper abdominal ultrasonography to objectively assess the ability of the former to detect cysts.Subjects and methodsOf 3704 patients who underwent special pancreatic US at our hospital, 186 underwent routine upper abdominal US within six months, had pancreatic cysts, and underwent magnetic resonance imaging (MRI). In these patients, 447 cysts measuring ≥5 mm were detected via MRI, which was used as the gold standard. The ability and sensitivity of the US modalities to detect each cyst was determined.ResultsThe sensitivity of special pancreatic US was 92.2% (95% confidence interval [CI], 89.7% − 94.7%) and that of routine upper abdominal US was 70.2% (95% CI, 66.0% − 74.5%). McNemar test (Stata Version 13.1) revealed a significant difference in the cyst (≥5 mm) detection sensitivity between the two modalities (p < 0.001). An analysis stratified by patients similarly revealed a significant difference between the two modalities (p < 0.001). The cyst detection sensitivity was also analyzed in various parts of the pancreas. The sensitivity of special pancreatic US was 88.7% for the uncinate process and inferior head, 97.5% for the head, 97.1% for the body, 89.0% for the body-tail, and 66.7% for the tail, whereas that of routine upper abdominal US was 74.2% for the uncinate process, 69.5% for the head, 81.0% for the body, 67.0% for the body-tail, and 26.7% for the tail. The McNemar test revealed significant differences in the sensitivity of the two modalities for all pancreatic parts (p < 0.001 − 0.016).ConclusionCompared with routine upper abdominal US, special pancreatic US had higher sensitivity in detecting pancreatic cysts.