AUTHOR=Blank Annika , Roberts Daniel Edward , Dawson Heather , Zlobec Inti , Lugli Alessandro TITLE=Tumor Heterogeneity in Primary Colorectal Cancer and Corresponding Metastases. Does the Apple Fall Far From the Tree? JOURNAL=Frontiers in Medicine VOLUME=5 YEAR=2018 URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2018.00234 DOI=10.3389/fmed.2018.00234 ISSN=2296-858X ABSTRACT=

Colorectal cancer harbors tremendous heterogeneity, with temporal and spatial differences in genetic mutations, epigenetic regulation, and tumor microenvironment. Analyzing the distribution and frequency of genetic, epigenetic, and microenvironment differences within a given tumor and between different sites of a metastatic tumor has been used as a powerful tool to investigate tumorigenesis, tumor progression, and to yield insight into various models of tumor development. A better understanding of tumor heterogeneity would have tremendous clinical relevance, which may manifest most clearly when genetic analyses to inform treatment decisions are performed on a very limited sample of a large tumor. This review summarizes the current concepts of tumor heterogeneity, with a focus on primary colorectal cancers and their corresponding metastases as well as potential clinical implications.