Genetic Factors Should Be Considered When Caring for Colorectal Cancer Survivors

Examples include changes in therapeutic approaches for chronic myelogenous leukemia with tyrosine kinase inhibitors, as well as use of gene expression platforms such as Oncotype DX and Mammaprint, which guide decisions about adjunctive (and often toxic) therapies for breast cancer. In colorectal cancer, testing patients for KRAS mutations may affect the choice of chemotherapy approaches and, likely, downstream recurrence risks and adverse effects.1 The authors' statement that “colorectal cancer survivors should be screened [for secondary cancers] according to the same guidelines used for screening in average-risk persons” seems problematic without added qualifications. The Centers for Disease Control and Prevention estimates that as many as one in 20 colorectal cancers results from an underlying hereditary predisposition due to a mutation in key pathways related to oncogenesis.