Biomarkers of pancreatic cancer.

Pancreatic cancer has a high mortality rate since early diagnosis is difficult and radical operation is challenging. Classical tumor markers are reliable parameters to determine disease progression during chemotherapy or recurrence after surgery, but they are not adequate to identify suspected disease or for screening. Endoscopic brushing cytology or biopsy from the stenotic duct is widely performed for the histological evidence of pancreatic cancer, but still suffers from low sensitivity. Recently, several molecules were found to be specifically expressed in pancreatic cancer, and these novel molecular markers are reported to improve the sensitivity of cytology or biopsy. In some cases, novel markers are tested for the diagnosis of cystic neoplasms. In addition, advances in endoscopic ultrasonography-guided fine needle aspiration biopsy enabled sampling of the cancer tissue before surgery or treatment, which delineates the individualized therapeutic strategy against pancreatic cancer, via the assessment of prognosis- or therapy resistance-related factors. Furthermore, novel transcriptomic or metabolomic biomarkers in the clinical samples collected by non-invasive methods, e.g. blood or saliva samples, are now applied for the diagnosis of pancreatic cancer. These methods will be beneficial for the screening and early detection of pancreatic cancer.