Pathobiology. 2018;85(1-2):72-84. doi: 10.1159/000486721. Epub 2018 Feb 7.
Colorectal cancer is not one disease but rather a collection of neoplastic diseases. Due to heterogeneity in the disease biology, therapy response, and prognosis, extensive disease stratification is required. Therefore, TNM stage, microsatellite status, tumor grade, lymphovascular invasion, and other parameters are assessed in the pathology report to indicate the extent and prognosis of the disease. The mutation status of KRAS, BRAF, and NRAS is also investigated in a metastatic context to predict the response to anti-EGFR therapy. Recently, 4 distinct molecular subtypes of colorectal cancer have been described that have both prognostic and therapeutic relevance. In addition, characterization of the inflammatory infiltrate revealed major differences in the amount and location of inflammatory cells in distinct colorectal tumor types. Together, all of these parameters help to stratify patients into different therapeutic and prognostic subgroups. However, this stratification is not unambiguous since tumors often display intratumoral heterogeneity, whereby several subpopulations within one tumor show differences in morphology, inflammatory infiltrate, mutational status, or gene expression profile. This article gives an overview of all of the current known data with regard to tumor heterogeneity at both inter- and intratumoral levels.
结直肠癌不是一种疾病，而是一组肿瘤性疾病。由于疾病生物学、治疗反应和预后存在异质性，因此需要广泛的疾病分层。因此，在病理报告中评估 TNM 分期、微卫星状态、肿瘤分级、淋巴血管侵犯和其他参数，以表明疾病的范围和预后。在转移的情况下，还研究 KRAS、BRAF 和 NRAS 的突变状态，以预测对抗 EGFR 治疗的反应。最近，已经描述了 4 种不同的结直肠癌分子亚型，它们具有预后和治疗相关性。此外，炎症浸润的特征揭示了不同结直肠肿瘤类型中炎症细胞的数量和位置存在显著差异。所有这些参数共同帮助将患者分层为不同的治疗和预后亚组。然而，这种分层并不是明确的，因为肿瘤通常表现出肿瘤内异质性，即一个肿瘤内的几个亚群在形态、炎症浸润、突变状态或基因表达谱上存在差异。本文概述了所有目前已知的关于肿瘤在肿瘤间和肿瘤内水平的异质性的数据。
