The significance of stromal collagen organization in cancer tissue: An indepth discussion of literature

It has become clear that carcinogenesis goes beyond tumor cell biology. Cancer research has acknowledged the importance of biological functions of the tumor-microenvironment, wherein not only cellular components seem to hold valuable information but also structural components like collagen fibers. Several studies have focused on the significance of stromal collagen fiber organization and reported on its role in cancer progression, invasiveness and treatment response. In this review, we discuss the different imaging methods for stromal collagen organization, followed by an in-depth discussion of current literature on in-vitro and animal experiments and human studies, highlighting its importance with respect to cancer progression, prognosis and prediction. We can conclude that collagen organization contains valuable information with regard to metastatic potential and clinical outcomes in cancer. However, the significance of an aligned versus disorganized collagen morphology differs between cancer types, implying more research is necessary before steps towards clinical implementation can be made.