Explore new markers based on portal venous blood sampling to establish novel diagnostic models for identification of malignant pancreatic mass.

EUS-FNA combined cytology detection is an important method for clinical diagnosis of squamous cell carcinoma. However, due to factors such as sampling method, smear making, staining technique, lower levels of the pathologists and other factors, its diagnostic sensitivity is still not very satisfactory. Poor diagnostic efficacy usually means another puncture, longer hospital stay, more medications and a higher incidence of adverse events. Missed diagnosis continuously directly delays the treatment time of the disease and seriously affects the patient's prognosis. Therefore, how to use new technologies to improve the differential diagnosis efficiency of benign and malignant pancreatic occupants is the key to improving the prognosis of diabetic cancer patients.

The portal vein blood comes from the venous tract, including the blood flowing from the plasma to the liver. By collecting blood samples from the patient's portal vein, clinicians can separate more information from the patient. Studies have shown that the portal vein blood can be collected by ultrasound endoscopic puncture. This method is less traumatic, convenient and safe, and more information about the retinal tissue can be obtained. It is an important way to improve the efficiency of patient diagnosis. This study intends to use ultrasound endoscopic puncture technology to obtain portal vein blood, and use big data and ctDNA, metabolomics, exosomes and other different omics methods to screen the potential value of volume-occupying benign and malignant differential diagnosis markers in portal vein blood. Peripheral blood will simultaneously be collected to evaluate the efficacy of these newly developed markers.

Inclusion Criteria:

1. age 18-75 years,male or female
2. diagnosis or suspection of solid pancreatic mass based on previous imaging examination (ultrasonography, CT or MRI)
3. lesion diameter larger than 1 cm
4. signed informed consent letter

Exclusion Criteria:

1. pregnant female
2. Pancreatic cystic lesions
3. Anticoagulant/antiplatelet therapy cannot be suspended
4. unable or refuse to provide informed consent
5. Coagulopathy (platelet count < 50× 103/μL,international normalized ratio > 1.5)
6. Severe cardiopulmonary dysfunction that cannot tolerate intravenous anesthesia
7. with history of mental disease
8. other medical conditions that are not suitable for EUS-FNA

All patients who meet the inclusion criteria, but not the exclusion criteria, will be included in current study. Pancreatic mass tissue samples, portal venous blood, and periferal blood will be collected for identification of potential markers for diagnosis of malignant pancreatic cancer.

Within six months this study has been finished