Pancreatic Ductal Adenocarcinoma: Characteristics of Tumor Microenvironment and Barriers to Treatment

Pancreatic ductal adenocarcinoma remains a highly aggressive disease, with a 5-year relative survival rate of 10%. Numerous barriers to treatment exist, such as dense desmoplasia, infiltration of immune suppressor cells, inhibitory cytokines, low effector T-cell infiltration, and low tumor mutational burden. These factors help form a highly suppressive tumor microenvironment unique to pancreatic ductal adenocarcinoma. This review outlines barriers to treatment of pancreatic ductal adenocarcinoma by discussing the unique characteristics of the pancreatic tumor microenvironment and the factors that contribute to making pancreatic ductal adenocarcinoma such a challenging disease to treat.