We are going to establish "organoid" models from pancreatic cancer biopsies achieved via EUS-FNA. Then the sensitivity of the selected FDA-approved anti-cancer drugs will be tested in these organoids.

The survival rate of pancreatic cancer, a kind of malignant tumor, remains poor due to lack of effective treatments. Recently, a new model called "organoid" has been generated from human and murine pancreatic cancer tissues. These organoids are developed from large pieces of surgical tissues or small biopsies taken from EUS-FNA guided samples. Here in our study we are going to establish "organoid" models from pancreatic cancer biopsies achieved via EUS-FNA. After successful generation of these organoids, we will treat them with the selected FDA-approved anti-cancer drugs, and assess the responses to these anti-cancer agents in our established organoids.

Inclusion Criteria:

• 1) Patients suspected to have pancreatic cancer who will receive EUS-FNA for diagnosis; 2) Patients who have signed the informed consent.

Exclusion Criteria:

• 1) Those who are under the age of 18; 2) Patients who have received adjuvant chemoradiotherapies or other anti-tumor therapies; 3) Patients with critical illness and cannot tolerate the operations; 4) Women who have been pregnant or are planning to be pregnant.

Patients suspected to have pancreatic cancer who are going to receive EUS-FNA operations for diagnostic purposes.