Utility of Contrast-Enhanced Harmonic Endoscopic Ultrasonography for Early Diagnosis of Small Pancreatic Cancer

This study aimed to assess whether contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS), compared to multidetector-row computed tomography (MDCT) and magnetic resonance imaging (MRI), is useful for early diagnosis of small pancreatic cancer (PC). Between March 2010 and June 2018, all three imaging modalities and surgery were performed for patients with a pancreatic solid lesion measuring ≤20 mm; diagnostic ability was compared among modalities. Fifty-one of 60 patients were diagnosed with PC (PC size in 41 patients: 11–20 mm; 10 patients: ≤10 mm). The sensitivity, specificity, and accuracy of CH-EUS, MDCT, and MRI for PC (11–20 mm) detection were 95%/83%/94%, 78%/83%/79%, and 73%/33%/68%, respectively. The diagnostic ability of CH-EUS was significantly superior compared with MDCT and MRI (p = 0.002 and p = 0.007, respectively). The sensitivity, specificity, and accuracy of CH-EUS, MDCT, and MRI for PC (≤10 mm) detection were 70%/100%/77%, 20%/100%/38%, and 50%/100%/62%, respectively. The diagnostic ability of CH-EUS tended to be superior to that of MDCT (p = 0.025). The sensitivity of MDCT for PC (≤10 mm) detection was significantly lower than that for PC (11–20 mm) detection (20% vs. 78%; p = 0.001). CH-EUS, compared to MDCT and MRI, is useful for diagnosing small PCs.