Contrast EUS of the Pancreas

Prospective Controlled Trial of Contrast Enhanced Endoscopic Ultrasound for Evaluation of Pancreas Lesions

RATIONALE: Endoscopic Ultrasound (EUS) is the leading method to evaluate the pancreas but there may be difficulty characterizing small lesions, tumors which are not adenocarcinomas and neoplasia in the setting of pancreatitis. INTERVENTION: The innovation in this project will be the addition of intravenous contrast to standard EUS examination if the pancreas. PURPOSE: The aim is to determine if contrast enhances the ability of EUS to accurately diagnose lesions and target biopsies, and to define the quantitative features of this method. STUDY POPULATION:The population will include patients with pancreas cysts, masses, and inflammation presenting for EUS as part of standard clinical care. METHODOLOGY: This will be a prospective tandem trial involving conventional EUS, followed by EUS with contrast, followed by subsequent quantitative processing of contrast EUS imaging. ENDOINTS:Study endpoints will include the yield contrast EUS to evaluate pancreas cysts, masses, and inflammation. The impact of contrast EUS to better target the FNA of the chosen lesion will be assessed. Intra and interobserver variability will be assessed by comparing conventional EUS and contrast EUS of each case in a random order (intraobserver agreement) and among a group of blinded endosonographers (interobserver agreement).

AIM Early detection of pancreas cancer and precursors lesions improves survival. The investigators aim is to gauge whether quantitative contrast endoscopic ultrasound (EUS) improves the evaluation of pancreas tumors and precursors lesions including cysts. DESIGN The study will be a prospective tandem contrast EUS trial. All EUS will be performed as part of standard clinical care. Conventional EUS Standard EUS will first be performed using the 180 series linear array echoendoscope (Olympus, Center Valley, PA). The alpha-10 image processor (Aloka America, Wallingford, CT) in B mode will be used to acquire images. A research coordinator will help to record key parameters. Thirty second cine clips of conventional EUS images will be captured to compare with contrast EUS clips and enable intra and interobserver variability comparison. Contrast Administration Definity contrast will be activated by 45 seconds of agitation (VialMix, Lantheus, North Billerica, MA) and injected through the intravenous peripheral line which is placed to administer fluids. The investigators will administer a bolus dose of 10microliter (microL)/kg within 30-60 seconds followed by 10ml of saline flush. Up to 2 bolus injections will be administered during each case and doppler sonography will be used between them to induce microbubble destruction. Contrast EUS: Following contrast administration prospective assessment will be performed using the Olympus endoscope and images processed using the Alpha 10 system. Harmonic detection conversion software installed on the alpha 10 processor to enable detection. Core parameters for comparison to conventional EUS will be captured prospectively. Quantitative Processing: For each bolus 30 seconds of cine imaging will be captured for post processing and for comparison with conventional EUS imaging (intra and interobserver variability). Images of the lesion (5mm x 5mm region) and adjacent normal tissue (5mm x 5mm) regions will be captured to facilitate quantitative assessment. Quantitative analytic software will then be used to generate time intensity curves and associated values including peak intensity (PI), time to peak (TTP), wash-in-slope (WIS), rise time (RT), mean transit time (MTT), and time from peak to one-half (TPH). DRUG/DEVICE INFORMATION Definity: Definity is an intravenous contrast agent. It is comprised of 1.1-3.3um micropheres containing perflutren (octafluoropropane) which is cleared by respiration. The gas is encapsulated lipid shells which are metabolized to free fatty acids and hepatically cleared. The Olympus 180 linear echoendoscope will be used in all procedures which are being done for standard clinical indications. The Aloka SSD-Alpha 10-Processor will be used for image capture. Post EUS quantitative processing will be performed using QLAB quantification software (Philips Healthcare, Bothel, WA).

Patients will receive intravenous contrast during EUS to assess whether it increases diagnostic yield of the examination

The yield of EUS versus contrast EUS to diagnose pancreas cystic lesions, mass lesion, and origin of pancreatitis.

The endoscopist will perform conventional EUS and classify the lesion as described below, this will be recorded by the research assistant prior to contrast EUS. Contrast will then be administered and the classification of contrast EUS recorded in real time. The gold standard to calculate the yields of the modality will be on pathology and clinical diagnosis at three and six months. Additionally we will assess whether contrast impacted assessment of size and diagnosis.

A) The decision to perform a FINE NEEDLE ASPIRATION of the lesion will be based solely on the standard EUS exam. After making the decision to perform the FNA contrast EUS will be performed. We will assess the degree to whether contrast administration helped to better target the FNA of the chosen lesion

Quantitative parameters of pancreas mass lesions will be performed by comparing the quantitative parameters post processing of adenocarcinoma, neuroendocrine and other lesion, and chronic pancreatitis. The final diagnosis will be based on pathology and 3 and 6 month follow up. Comparison variables will include time to peak (SECONDS), rise time (SECONDS), mean transit time (SECONDS), and time from peak to one-half (SECONDS).

Inclusion Criteria: Patients undergoing endoscopic ultrasound for standard pancreatic indications. Patients must have unexplained pancreatitis, pancreas mass(es), or pancreatic cystic lesions (>1cm or worrisome features on imaging). Exclusion Criteria: Patients <18 years of age, pregnant women, and lactating mothers will be excluded. Subjects with unstable ischemic disease will be excluded. Additionally, those with known or suspected right-to-left, bi-directional, or transient right-to-left cardiac shunts will be excluded given theoretical (though clinically insignificant) risk of embolization. Patients with an allergy to Definity will be excluded.

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