May 10 2017
Pancreatic ductal adenocarcinoma (PDAC) is devastating. Because of its silent nature, the disease is often only diagnosed once it has reached an advanced, frequently inoperable stage. To date, we have no biomarkers that facilitate earlier diagnosis, leaving sufficient time for curative therapy that effectively lowers the very high mortality rate of this cancer entity. Because of this, the life expectancy of patients with PDAC is low (i.e. < 6% five-year survival rates). New data, including particular genetic signatures and features of the stromal architecture of PDAC tumors, may better explain their aggressiveness, their relatively long-lasting painless expansion, and why chemotherapy so frequently fails. The typical tumor-induced stromal desmoplasia is characterized by cancer-associated fibroblasts (CAFs), decreased immune surveillance, cancer-associated neural remodeling, and a very low vascular density. This stromal microenvironment generates hypoxia, nutrient deficiency, immune suppression, and chemoresistance. The combination of factors results in a vicious disease that begins with the long-lasting, asymptomatic development of a large tumor mass, followed by a delayed diagnosis with a high percentage of inoperable states, exhibiting a poor response to all conservative therapeutic options, including radiation, and which ends with metastasis resulting in a rapid fatal outcome. In this article, we review coherences on genetic, cellular, immunological, Nano medical and stromal characteristics of PDAC tissue, and discuss metabolic abnormalities associated with and/or preceding the tumor progression rate. A more comprehensive understanding of the underlying mechanisms can improve the diagnostic and therapeutic management of patients suffering from this devastating type of cancer.