EUS-guided PORtal Vein Sampling for Circulating Tumor Cells in Pancreatic Cancer Patients

EUS-guided PORtal Vein Sampling for Isolation, Enumeration and Profiling of Circulating Tumor Cells in Pancreatic Cancer Patients

The study aims at evaluating the feasibility and safety of EUS-guided Portal Circulation sampling for isolation, enumeration and profiling od Circulating Tumor Cells (CTC) in Pancreatic Cancer patients.

Patients undergoing Endoscopic Ultrasound (EUS) for cyto/histological characterization of the neoplasia will receive an additional Fine Needle Aspiration sampling of a branch of the Portal Circulation to obtain a blood sample which will be processed for CTC enrichment, count and characterization.

Prognostic stratification of patients with Pancreatic Ductal Adenocarcinoma (PDAC) is still suboptimal, relying only on imaging studies and Carbohydrate Antigen 19.9 to drive important treatment decisions (e.g. surgery versus neoadjuvant chemotherapy).

Circulating Tumor Cells (CTCs) have been poorly evaluated in this neoplasia as they are rarely detected in the peripheral blood, whereas they are more abundantly detected in the portal circulation below the hepatic filter.

Most PDAC patients undergo Endoscopic Ultrasound (EUS) for cyto/histological characterization of the neoplasia. EUS-guided acquisition of portal blood for CTC evaluation has demonstrated its feasibility in preliminary studies without reducing the safety of the endoscopic procedure.

The study aims at collecting portal blood from PDAC patients under EUS-guidance to evaluate whether concentration and characterization of CTCs has a prognostic significance and can aid in decision making.

A paired peripheral blood sample will be acquired for comparison. Samples will be processed to obtain microfluidic enrichment of CTCs and stained with immunofluorescent antibodies for exclusion of hematopoietic cells and specific identification of CTCs, which will then be counted to obtain the blood concentration expressed as number of cells per 7.5 ml of blood.

Patients will be followed every 60 days for a maximum of 24 months to assess the evolution of primary disease and clinical status.

Inclusion Criteria:

• patient with a pancreatic solid lesion undergoing EUS with a rapid on-site confirmation of a pancreatic ductal adenocarcinoma
• patients primarily followed within San Raffaele Institute

Exclusion Criteria:

• history of active non-pancreatic cancer
• coagulopathy (INR > 1.5; platelets < 70.000/ul) or use of non-withdrawable anticoagulant or antiplatelet
• known history or endosonographic signs of portal hypertension
• extensive invasion of portal vein precluding needle maneuvers
• pregnancy and breastfeeding