RATIONALE: Pancreas tumor localization makes minimally invasive surgical resection of pancreas tumors very challenging. Recently, an endoscopic ultrasound needle system has been developed which enables fiducial coils to be placed at the precise site of biopsy.

INTERVENTION: At time of EUS guided biopsy the fine needle fiducial device will be used to place fiducials in the tumor. During surgery we will assess whether it improves tumor visualization.

OBJECTIVES: We aim to determine the feasibility to use EUS guided fiducials placement to mark pancreas tumors in 20 patients and to assess whether the fiducials impact tumor visualization during pancreas surgery.

STUDY POPULATION: Patients with pancreas adenocarcinoma or neuroendocrine lesions.

STUDY ENDPOINTS: The main outcome will be to assess whether the coil may be successfully placed during EUS and whether they impact tumor visualization during surgery FOLLOW UP and ANALYSIS: Patients will be assessed at the time of EUS and surgery. This is a pilot analysis with the intention to assess feasibility and to gather data to power larger trials.

Minimally invasive pancreatic surgery diminishes the morbidity and mortality of the potentially curative procedures. However precise targeting of small adenocarcinomas and neuroendocrine tumors is challenging.

Given safety, precision, and ease EUS guided pancreatic fiducial placement has emerged as a favored method to mark tumors for radiation therapy. The experimental aspect of this procedure is gauge whether EUS guided fiducial placement improves the intraoperative assessment of pancreas tumors. We will use the recently introduced (FDA approved) Beacon EUS guided fiducial system to perform placement. The fiducial will not alter the surgical plan in this study. However, the relative ability to detect the marker during standard pancreatic surgery will help to inform whether this strategy may be used in improve future approaches to pancreas surgery.

The study will be a prospective trial. All EUS will be performed as part of standard clinical care.

Conventional EUS+FNA The linear array echoendoscope will be used to identify the pancreas adenocarcinoma and neuroendocrine tumors. The Beacon EUS system/delivery sheath will be passed and fine needle aspiration performed to confirm cytology. This is required for standard clinical care. The delivery sheath will be left in place. The cytologist will perform bedside interpretation as is standard clinical care.

EUS guided coil injection If adenocarcinoma or neuroendocrine tumor is confirmed by fine needle aspiration the fine needle fiducial accessory will be passed through the delivery sheath (whose position on the tumor is now "biopsy confirmed" and 1-3 fiducials (coil type) will be introduced into the lesion. This process will be guided by EUS which is being performed for standard clinical care. Fluoroscopy not be utilized.

Pancreas Surgery: At time of surgery the experimental component is that it will be gauged whether the fiducial impacts the ability to assess the tumor relative to lesions of comparable size. Whether the fiducial improves or does not improve assessment will be scaled on a 1-10 scale where 5 is the standard ease of detection of similarly sized tumors (without fiducials) based on the attending surgeon's experience.

However, the fiducial will not be used to target the lesion or alter the surgical plan. The surgical plan will be based on preoperative clinical imaging, intraoperative findings, and intraoperative ultrasound (standard clinical care). The research coordinator will be present during surgery to facilitate timely acquisition of data. In some cases patient are deemed to not be resection candidates at the time of surgery if for example unexpected metastasis are found. The EUS guided fiducial placement will have no bearing on whether resection is done or not.

Inclusion Criteria:

Patients undergoing endoscopic ultrasound for preoperative evaluation before planned pancreatic surgery for suspected adenocarcinoma and neuroendocrine tumors will be eligible. Rapid onsite evaluation is performed for all pancreas EUS as part of standard procedures. In this process the cytologist examines the cells and makes a determination whether the aspirate contains malignant or benign tissue. Fiducials will only be placed if cytologic confirmation of malignancy at the site is obtained.

Tumors of sizes 5mm-4cm will be eligible as there may be benefit in marking small tumors given difficulty finding them with intraoperative ultrasound. Moderately large pancreas tumors may also cause fibrosis which makes identification for resection difficult. Coil placement in regions of cytologically confirmed malignant cells may be helpful. Fiducial markers will only be placed if the initial evaluation (abdominal computed tomography or magnetic resonance imaging) indicates resectability. If finding of nonresectability (i.e. liver metastasis) are seen on EUS then fiducials will not be placed.

Exclusion Criteria:

• 1) Patients with INR >1.5 2) Platelet county <100 3) Metal allergy 4) Pregnant 5) <18 years of age 6) Patients with pancreatic lymphoma will also be excluded as this is treated with chemotherapy.