Heterotopic pancreas: the added value of endoscopic ultrasound with Computed Tomography for diagnosis.

Aims: To investigate the added value of endoscopic ultrasound (EUS) with computed tomography (CT) in distinguishing heterotopic pancreas (HP) from other pathologies, when gastroduodenal subepithelial tumors (SETs) are suspected on an upper endoscopic examination.

Material And Methods: We retrospectively included 54 consecutive patients with gastroduodenal SETs who had undergone both abdominal CT and EUS within a 3-month interval. All EUS, endoscopy, and CT images were reviewed and evaluated in a blinded manner by an endoscopist and a radiologist, respectively. Univariate and multivariate analyses were performed to identify EUS/CT findings related to HP. Diagnostic performance of CT only and CT combined with EUS was compared for distinguishing HP from other SETs.

Results: We included patients with HP (n=17; pathologically confirmed, n=6), gastrointestinal stromal tumor (GIST, n=24), and other pathologies (n=13). Multivariate logistic regression analyses revealed that irregular margin, origin from submucosal layer, internal microcystic-tubular structure, and oval shape were independent factors in diagnosing HP by EUS, whereas a micro-lobulating contour was the only significantly independent factor in CT. In assessments of diagnostic performance, CT combined with EUS showed significantly superior diagnostic performance in comparison with CT only (area under the curve, 0.961 vs. 0.833, p=0.028) in the consensus interpretation of an endoscopist and a radiologist.

Conclusions: CT combined with EUS with a comprehensive and complementary interpretation showed significant added value compared to CT only in diagnosing gastroduodenal HP.