The treatment performance of pancreatic cancer has not changed significantly over the past 20 years and is still less than 10%. In addition, 80-90% of pancreatic cancer patients are found to be already advanced at the time of diagnosis, and it is the best malignant tumor in the human body with a 5-year survival rate of less than 10% and a median survival period of less than 1 year. However, early diagnosis of pancreatic cancer is still difficult, and there is no effective treatment other than surgery, so the increase in long-term survival rate over the past 20 years has been insignificant or stagnant. The response rate to anticancer drug treatment after surgery or anticancer drug when surgery is not possible is only around 20%, so it is very urgent to discover new biomarkers in predicting drug resistance and recurrence after surgery and predicting prognosis in advance. Minimally non-invasive diagnostic techniques are very important to detect and track cancer progression in the clinic. In particular, histological diagnosis and analysis have limitations in carcinomas, such as pancreatic cancer, which are small and distant, making it difficult to obtain tissue samples. CA 19-9, a prognostic marker for existing pancreatic cancer, 1) has low specificity for early diagnosis of pancreas, 2) is not detected in lewis A, B antibody-negative patients, and 3) shows false positive in cases with cholangitis at the same time. Because it has many disadvantages, the development of prognostic biomarkers in blood is urgently needed.

Recently, a study has been reported that the presence or absence of detection of circulating tumor cells is directly related to the prognosis of pancreatic cancer patients, and can be used for monitoring the patient's treatment response and for recurrence after surgery. In particular, the process of cancer metastasis consists of epithelial-to-mesenchymal transition and migration of cancer cells into the blood, and the existence of cancer stem cells is very important for metastasis and drug treatment resistance. Eventually, it is known to cause pancreatic cancer metastasis and recurrence.

Cancer stem cells have the ability to self-renew, the capability of developing, multiple cell lineages, and the potential of extensive proliferation, and the ability to detect cancer stem cells in the blood is important in pancreatic cancer patients who are at high risk of metastasis and recurrence. It is a non-invasive screening tool. Comparatively evaluate the treatment response and prognosis of pancreatic cancer patients according to the characteristics and subtypes of circulating cancer cells.

Inclusion Criteria:

• Men and women over 20 years of age
• Patients diagnosed with pancreatic cancer histologically or radiologically

Exclusion Criteria:

• non-pancreatic cancer
• Patients who failed to obtain informed consent from the patient

Patients over the age of 20 who have been diagnosed with pancreatic cancer histologically or radiologically.