Contrast Harmonic Endoscopic Ultrasonography in the Characterization of Pancreatic Metastases (With Video)

Objective The differential diagnosis between primary pancreatic neoplasms versus pancreatic metastases (PM) is challenging. Endoscopic ultrasonography with fine-needle aspiration can be used to differentiate primary versus metastatic tumors although with a suboptimal accuracy. Recently, contrast harmonic EUS (CH-EUS) has been reported as an adjunct in the diagnosis of pancreatic neoplasms. We evaluated the potential role of CH-EUS in the differential diagnosis of PM. Methods This study is a retrospective analysis of a prospectively maintained database. Of the 266 patients, 4.1% were diagnosed with PM. Endoscopic ultrasonography with fine-needle aspiration and/or surgical pathology represented our criterion standard. Results The origins of PM were renal cancer (3 patients), colon cancer (2 patients), breast cancer (2 patients), ovarian cancer (1 patient), melanoma (1 patient), lymphoma (1 patient), and sarcoma (1 patient). All lesions appeared hypoechoic at standard EUS. At CH-EUS, of the 11 lesions, 6 appeared hypoenhancing (colon cancer, sarcoma, and breast and ovarian cancer), 4 were hyperenhancing (renal cancer and lymphoma), and 1 was isoenhancing (melanoma). Conclusions In our population, standard EUS features of PM were unremarkable. At CH-EUS, most of the PM appeared hypoenhancing suggesting a possible malignant origin. However, a subset of PM showed hyperenhancing pattern. In the appropriate context, particularly when cancer history is present, CH-EUS may add to the differential diagnosis and potentially spare endoscopic ultrasonography with fine-needle aspiration.