In the formation and growth of a primary tumor, cells can released into the bloodstream. There are many researches for these circulating tumor cells(CTC) And recently circulating cell-free tumor DNA(ctDNA) released from apoptotic or necrotic tumor cells has developed. At one report which checked ctDNA level after operation of colon cancer patients, they suggested that ctDNA could show recurrence of cancer several months earlier than the conventional follow up imaging. And several reports suggested that ctDNA can invade host cell and change host cell biology, which can evoke cancer metastasis.
So in this study, the investigator will collect ctDNA of pancreatic cancer patients, benign pancreatic disease patients, and healthy population. And the investigator will evaluate whether peripheral ctDNA can help early screening of cancer recurrence. And we will study about genomic signature of ctDNA to evaluate relationship between ctDNA and clinical outcome of cancer patients.
